LinuxMCE Forums

General => Feature requests & roadmap => Topic started by: reidfo on April 01, 2007, 10:57:49 pm

Title: Single NIC installation
Post by: reidfo on April 01, 2007, 10:57:49 pm
I would really like the option for a single NIC install, where LinuxMCE doesn't try to act as my router. For those of us with a perfectly good router already, and want to experiment with LinuxMCE, this is a big issue.
Title: Re: Single NIC installation
Post by: 1audio on April 02, 2007, 08:16:56 am
It can be done, I'm using it that way now. But you need LMCE to be the DHCP server to get the media directors to work and the PNP setup feature to work.

you configure the two functions under networking like this-
1) disable the router's DHCP server
2) Set the cores's IP to static and in the same range as the router.
3) enable the DHCP server and make sure its in a different range (LMCE uses 192.168.80 )
Title: Re: Single NIC installation
Post by: Elluminatus on May 24, 2007, 11:45:55 am
But I think the option that a Router can do all the DHCP stuff would be great to!!
Because all of us using a Ipcop router ore something like this it is not so nice to disable the easy to use configuration of the blue, orange and green net especially when you recognize that people would like to put Linuxmce in the DMZ...

Just my 2 cents
Elluminatus
Title: Re: Single NIC installation
Post by: Hugolp on May 25, 2007, 01:11:40 am
But if the linuxmce machine is not the dchp router it can not control when new media has been pluged and detect it to play it making the whole system more complicated.

Just make two networks like linuxmce suggest. One external with the router acting as a dchp server and the linuxmce core with an static ip, and the internal conected to the core that acts as a dchp server and nat firewall internet gateway. That way you plug your media directors to the internal network and the other computers to the external network. A pci gigabit ethernet card costed me 15 euros a month ago, and a gigabit 5 port swicht for my internal network costed me 25 euros, so its not expensive to do that set up.
Title: Re: Single NIC installation
Post by: Cryoniq on May 27, 2007, 05:47:58 am
Single NIC option would be nice. I have struggled with problems currently which I belive is related to the fact that I set first NIC to 192.168.1.150 and second to, at first, 192.168.80.*

That didn't go well at all with shares etc it seems. Discovered nothing, since all equipment is in fact on the 192.168.1 network.

Why is that?

I have a hardware firewall/router with NAT, built in DHCP etc. All computers get their info from it and communicate through that device. It is small, cheap to run energywize etc. If I would make LMCE the router with DHCP enabled I would have to move all exisiting equipment over to the other network, which isn't practical at all. They already have what they need and a firewall to protect them and gateway. It would toss out IP to any other device in the home, either through ethernet or aerial wireless.

Another thing is that one might not want all features of LMCE. My interest was media playback and connect shares to it from where it could store and get videos, pictures, music from, as well play dvd's and rip them over to harddrive, either localy or remote network shares. Also when I choosen a good tv card use its TV features and use it as a VCR. And that is it, for the time being.

I am not saying to just have 1 NIC installed. I am saying that the install should have option to configure it with just 1 NIC, either ethernet or wireless NIC and it could talk through that and not act as a router, but mainly as a media station.

I also think that this is the main features that most are interested in at the moment. Not many have a home security system, nor security cameras, and they do not have the need for voice mail, don't have lighting system etc. I am pretty sure that the media features are in mind at a huge % of the crowd.
And as it is now, I would, as a developer, concentrate on those areas. I hope noone take offense for me saying that. I am really excited about LMCE and it is a task developers shall have credit for, even if it is a bit messy and weird atm.

LMCE with just the media features and functions working alone kick Windows MCE in the nuts many times over to start with. So it would be no shame at all sort out the installation, media part and option as it as a media center for tv, video and musik to start with. :P
Title: Re: Single NIC installation
Post by: jpelzer on May 28, 2007, 04:21:16 pm
Talk about 'Single NIC' and 'no DHCP' seems to have veered from the original topic. One shouldn't need to use MCE as a router to use it as a DHCP server. This shouldn't even be a change within the core MCE, it's just adding an option to the install to NOT try to create a second network. My guess is that 99% of the users of MCE already have a router that is more functional than what MCE gives them (out of the box).

The best analogy for this that I can come up with is go to a store to buy an air freshener and be forced to buy a car to put it in.
Title: Re: Single NIC installation
Post by: PeteK on May 28, 2007, 05:24:23 pm
The thing to keep in mind is that this system was designed to be THE computing system in a house.  As such, it was assumed that the network for the home could be configured around it.  Actually, having two NICs and having your core act as your router for the devices attached to your LinuxMCE core makes a pretty nice sandbox to play with the system.  At least it does for me.  Jpelzer does bring up an excellent point in that DHCP can be utilized independently of the router (though I'm not sure LinuxMCE can do this right now).  I know Pluto gives the option of a single NIC install when the system is installed.  I guess the LinuxMCE developers removed that in the fork.  Is that correct?
 
To throw my $.02 in:

1) Pluto provided an opportunity for a single NIC install, so performing that with LinuxMCE should be fairly easy to do, but:
2) The PNP functionality of the LinuxMCE system is really neat, and I think important to expand the attractiveness of the system beyond the hardcore tinkerers who are playing with it now.
3) I respectfully disagree with Cryoniq that the voicemail, lighting, security features are not that important.  If I want just a media center with tv and video, I can use Myth and be done.  The strength of LinuxMCE/Pluto lies in the fact that it ties together all the disparate peices of hardware and software to create a cohesive system that makes sense and can allow control of a complex system through a (semi-intuitive) interface.  The fact that there are a lot of issues with the implementation still means that that is where the developers (I hope to be included) should spend their effort, as that is the true magic happens.
Title: Re: Single NIC installation
Post by: Cryoniq on May 28, 2007, 11:16:02 pm
The thing to keep in mind is that this system was designed to be THE computing system in a house.  As such, it was assumed that the network for the home could be configured around it.  Actually, having two NICs and having your core act as your router for the devices attached to your LinuxMCE core makes a pretty nice sandbox to play with the system.  At least it does for me.  Jpelzer does bring up an excellent point in that DHCP can be utilized independently of the router (though I'm not sure LinuxMCE can do this right now).  I know Pluto gives the option of a single NIC install when the system is installed.  I guess the LinuxMCE developers removed that in the fork.  Is that correct?
 
To throw my $.02 in:

1) Pluto provided an opportunity for a single NIC install, so performing that with LinuxMCE should be fairly easy to do, but:
2) The PNP functionality of the LinuxMCE system is really neat, and I think important to expand the attractiveness of the system beyond the hardcore tinkerers who are playing with it now.
3) I respectfully disagree with Cryoniq that the voicemail, lighting, security features are not that important.  If I want just a media center with tv and video, I can use Myth and be done.  The strength of LinuxMCE/Pluto lies in the fact that it ties together all the disparate peices of hardware and software to create a cohesive system that makes sense and can allow control of a complex system through a (semi-intuitive) interface.  The fact that there are a lot of issues with the implementation still means that that is where the developers (I hope to be included) should spend their effort, as that is the true magic happens.

Oh that is ok. I am just pointing out that right now there seem to be a need to fix the media functions. Of course voicemail. lighting, security features are important to LMCE as a whole; But we are in beta right now and one have to start somewhere and work from the top and out. The media functions like TV, Video, Music, Pictures, Remotes and mount of information via local drives and shares are what drawn most of the people towards LMCE. I discovered LMCE from a discussion on a IT news resource forum and many people thought it looked awesome and all made remarks about just those parts and issued strong interest for them.

Of course I realise that everyone cannot work on those things and some doesn't have the knowledge and experience of that, which will work and develope the voicemail, security etc. I am not saying those people should drop what they doing and turn on the media features. Just so noone think I am doing that.

I am sure these things are adressed as we.. uhm write.. and that it is a concern and goal of the developers as well naturally. So I point out that I am not ranting, even if it might seem like it. I just think LMCE got huge potential and I would love to see the interest explode around it. But in order for that the install have to be close to flawless and easy and the main parts that draw most people to it need to work.

I might seem irritated from time to time. But that is out of the fact that I discovered LMCE, watched the video and everything was under PR flag that it was just pop in ubuntu, download and install and things would be taken care of and ready for showtime. And that turned out to be very far away. So after spending several days and nights fiddling with it all and headaches it gets very frustrating.
I really hope people haven't been scared away experiencing the same as I have and that they stay tuned and realise this is a work in progress of course. :)

I will try do my best to submit feature requests and bug reports to make LMCE  grow and flourish :) And I will yell when something is wrong, but I do it out of love for LMCE (omg that was covered in pink and fluff!) :P
Title: Re: Single NIC installation
Post by: totallymaxed on May 29, 2007, 12:33:11 am
The thing to keep in mind is that this system was designed to be THE computing system in a house.  As such, it was assumed that the network for the home could be configured around it.  Actually, having two NICs and having your core act as your router for the devices attached to your LinuxMCE core makes a pretty nice sandbox to play with the system.  At least it does for me.  Jpelzer does bring up an excellent point in that DHCP can be utilized independently of the router (though I'm not sure LinuxMCE can do this right now).  I know Pluto gives the option of a single NIC install when the system is installed.  I guess the LinuxMCE developers removed that in the fork.  Is that correct?
 
To throw my $.02 in:

1) Pluto provided an opportunity for a single NIC install, so performing that with LinuxMCE should be fairly easy to do, but:
2) The PNP functionality of the LinuxMCE system is really neat, and I think important to expand the attractiveness of the system beyond the hardcore tinkerers who are playing with it now.
3) I respectfully disagree with Cryoniq that the voicemail, lighting, security features are not that important.  If I want just a media center with tv and video, I can use Myth and be done.  The strength of LinuxMCE/Pluto lies in the fact that it ties together all the disparate peices of hardware and software to create a cohesive system that makes sense and can allow control of a complex system through a (semi-intuitive) interface.  The fact that there are a lot of issues with the implementation still means that that is where the developers (I hope to be included) should spend their effort, as that is the true magic happens.

All our Core's are single NIC now... and we have no problems with that config under lmce at all. It works fine... no different to the way it did under Pluto in fact.
Title: Re: Single NIC installation
Post by: bobpaul on June 21, 2007, 07:26:25 pm
All our Core's are single NIC now... and we have no problems with that config under lmce at all. It works fine... no different to the way it did under Pluto in fact.

How exactly is that configured?

It seems to me I should be able to do at least 1 of 2 setups for Single NIC setup:

NIC has two IP addresses.
Main router is 192.168.1.1 which has DHCP disabled. LMCE runs static 192.168.1.10 to connect to the router (and thus internet) and static 192.168.80.1 to serve DHCP and gateway for other systems on the network, routing traffic to 192.168.1.1 router. This doubles the traffic on the NIC as data comes in on the .80.x network and leaves the same port bound for the .1.x network. The main router would have to have an entry for the .80.x network if port forwarding was required on client machines. It's also possible the main router config tool only allows forwarding to addresses on the .1.x network, regardless of manual routing table entries (Linksys stock firmware, for example).
This seems to be the default for LMCE, or am I wrong?

LMCE for DHCP only, no routing.
Main router is 192.168.1.1 with DHCP disabled. LMCE runs static 192.168.1.10 to serve as DHCP server. DHCP packets setup clients to use 192.168.1.1 as default gateway but to network boot from 192.168.1.10. All computers are still on the .1.x network, so no considerations need to be made from the main router perspective for things like port forwarding.
This is how I would prefer and intend to setup and seems to be the most sensible setup for a single NIC system.

During the install I told it my network base was 192.168.1 and it immediately assigned a second IP to the NIC of 192.168.1.1, causing a conflict with my main router. It seems I need to manually configure the network to set it up as I want.
Title: Re: Single NIC installation
Post by: bobpaul on June 22, 2007, 07:43:06 am
Ok. I made SOME progress on option 2, though option 1 seems to be the default and works fine, I don't like it cause I'm pretty sure that would double internet bound traffic on that 1 link making that a significant congestion point (not to mention that it already has all of that media streaming out of it).

If you edit /etc/dhcp3/dhcpd.conf and change "option routers" to 192.198.1.1 it will setup your default gateway to be that. You can now turn off DHCP on your router and LinuxMCE will take over DHCP, but set your actual router up as the default gateway. If you want, you can also add additional nameserver lines to list your actual router as a name server, your isp's nameservers, etc. This works fine and LinuxMCE can detect new devices, but network boot doesn't work.

The problem is that network boot requires that the primary default gateway (router) is LinuxMCE. The work around would appear to be setting up groups. Comment out the two lines beginning "filename" and "option pxe" in the subnet group. This will prevent pxe boot from most of your machines.

Now alter the following like so:
Code: [Select]
# PXE booting machines
group {
        option routers 192.168.1.10;
        next-server 192.168.1.10;
        filename "/tftpboot/pxelinux.0";
        option pxelinux.reboottime = 30;

        host vmware { hardware ethernet 00:0c:29:0c:66:f4; }
}

I added the option routers line and the host line. The option routers line means "for machines that boot from PXE, use this as the default gateway instead of the default declared above." The host line means "this host arbitrarily called vmware has the hardware address of __ and belongs to this group" That is to say, if you have to declare each machine you want to network boot to be IN the network boot group. Only the machines listed (each on it's own line with name and mac) will boot form the network and use LMCE as their default gateway. That way, it will only be THOSE machines who double their internet traffic, and chances are these machines won't access the internet, unless they also double as a PC.

Unfortunately, the above doesn't work. I'm declaring how a host is in a group improperly, and I can't figure it out from the man page. If someone with dhcpd experience can correct me, that'd be great. Until then, all but network boot works.
Title: Re: Single NIC installation
Post by: bobpaul on June 24, 2007, 12:43:10 am
I got it! The host declaration also requires a fixed-address line to set a static-dhcp address. According to the manpage, this is not so, but when I added that in, it worked. So, modify for your use the attached config. Results are as follows:

Pro:
*Only 1 network is run, 192.168.1.x
*Most hosts on the network utilize the main router, 192.168.1.1

Con:
*Machines that PXE boot will use LMCE as their default gateway. This then routes the traffic back out the same nic to the main router.
*Machines using PXE boot must be listed individually
*Machines use PXE boot must have a fixed-address applied by dhcp. This is not a big deal, but requires more coordination on your part.

/etc/dhcp/dhcpd.conf
Code: [Select]
# option definitions common to all supported networks...
#option domain-name "fugue.com";
#option domain-name-servers toccata.fugue.com;
option domain-name-servers 192.168.1.10;   #I'm running dnsmasq on the LMCE Core
option domain-name-servers 192.168.1.1;
authoritative;

option subnet-mask 255.255.255.0;

# lease IPs for 1 day, maximum 1 week
default-lease-time 86400;
max-lease-time 604800;

allow booting;
allow bootp;

option space pxelinux;
option pxelinux.magic code 208 = string;
option pxelinux.configfile code 209 = text;
option pxelinux.pathprefix code 210 = text;
option pxelinux.reboottime code 211 = unsigned integer 32;

subnet 192.168.1.0 netmask 255.255.255.0 {
        next-server 192.168.1.10;
        option routers 192.168.1.1;

        default-lease-time 86400;
        max-lease-time 604800;
        pool {
                 allow unknown-clients;
                 range 192.168.1.151 192.168.1.254;
        }
}

# PXE booting machines
group {   
        next-server 192.168.1.10;
        option routers 192.168.1.10;
        filename "/tftpboot/pxelinux.0";
        option pxelinux.reboottime = 30;

        host vmware {
               hardware ethernet 00:0c:29:0c:66:f4;
               fixed-address 192.168.1.20;
         }
}

# regular machines
group {
}

# CORE (1) has bad mac address:

Change the IPs to match your network. Change the name "vmware" to some name for that host. Change the mac address to match your host's mac address. Change the fixed-address to something that won't cause conflicts.
To add hosts, add more host sections in that group.
Title: Re: Single NIC installation
Post by: totallymaxed on June 25, 2007, 05:19:33 pm
All our Core's are single NIC now... and we have no problems with that config under lmce at all. It works fine... no different to the way it did under Pluto in fact.

How exactly is that configured?

It seems to me I should be able to do at least 1 of 2 setups for Single NIC setup:

NIC has two IP addresses.
Main router is 192.168.1.1 which has DHCP disabled. LMCE runs static 192.168.1.10 to connect to the router (and thus internet) and static 192.168.80.1 to serve DHCP and gateway for other systems on the network, routing traffic to 192.168.1.1 router. This doubles the traffic on the NIC as data comes in on the .80.x network and leaves the same port bound for the .1.x network. The main router would have to have an entry for the .80.x network if port forwarding was required on client machines. It's also possible the main router config tool only allows forwarding to addresses on the .1.x network, regardless of manual routing table entries (Linksys stock firmware, for example).
This seems to be the default for LMCE, or am I wrong?

LMCE for DHCP only, no routing.
Main router is 192.168.1.1 with DHCP disabled. LMCE runs static 192.168.1.10 to serve as DHCP server. DHCP packets setup clients to use 192.168.1.1 as default gateway but to network boot from 192.168.1.10. All computers are still on the .1.x network, so no considerations need to be made from the main router perspective for things like port forwarding.
This is how I would prefer and intend to setup and seems to be the most sensible setup for a single NIC system.

During the install I told it my network base was 192.168.1 and it immediately assigned a second IP to the NIC of 192.168.1.1, causing a conflict with my main router. It seems I need to manually configure the network to set it up as I want.

Here is how we setup all our Pluto/lmce systems;

The Hybrid/Core has a single NIC. Physically the Hybrid/Core is connected to the LAN port of a Wireless AP/Router the other MD's are also connected to LAN ports on the Wireless AP/Router. The broadband is connected to the WAN port on the Wireless AP/Router.

The Hybrid/Core is configured with its Internal LAN in the IP address range 192.168.80.2 to 80.128 for MD's and 80.129 to 80.240 for none MD devices. The Hybrid/Core is on the fixed address of 192.168.80.1. The External WAN side address the Hybrid/Core is set to a fixed address of 192.168.20.99 and its gateway address is set to 192.168.20.1 (which is the Wireless AP/Router)

We have several Core's setup this way and it wirks fine. Hope this helps

Andrew
Title: Re: Single NIC installation
Post by: ariznaf on June 30, 2007, 01:54:06 am
I have a LMCE installation similar to the one described byt TotallyMaxed and the core works perfectly: it has 192.168.1.250 as external ip address (connected to a adsl router in 192.168.1.254) and an internal addresss 192.168.2.250 acting as a DHCP server in that net.
I have turned off the DHCP server in the ADSL router.
I have other computer (running windows vista) that takes addresses from LMCE dhcp server (it take 192.168.2.249 address) and using the MCE as its gateway...
BTW when the MCE computer is down - it shouldn't but i am testing the MCE hybrid install and the MD isn't working yet- i have configured a second static address in my vista computer as 192.168.1.1 and the gateway IP address of the adsl router 192.168.1.254. Thus i can surf internet in the vista computer even if the MCE computer is turned off, just have to reboot or reload the network interfaces.

I agree that DHCP server in LMCE is crucial for its functionality. If you want just a media server, there are many other options. Media server is just one of the things the LMCE can do. It is a residential gateway and thus it is the central point of communications and security of our home network. It has to take control of IP given and new devices connected, and for that, being the DHCP server makes lot of sense.
Taking control of all devices in the home assures security and future changes and developement in the LMCE without afecting the devices and without having to install software in the devices to interoperate with the LMCE system.

Anyway you can turn off the DHCP server in MCE, but you loose the new device detection from LMCE: for detecting a device it has to ask for an IP - it cannot be detected if you use a static ip, either- and LMCE must serve the IP addresses.

May be there are other ways of detecting new devices, but are not so clean.
Title: Re: Single NIC installation
Post by: bobpaul on September 07, 2007, 06:15:31 am
The problem with the 2 router method (your existing router and the core system as a router with DHCP services enabled on the internal network with effectively a DMZ in between) is that the most people have a wireless router as their existing router.  This means that wireless devices get their IP addresses assigned by your original router in the DMZ and so LMCE never sees them. 

This is entirely false. If you turn off DHCP on your wireless router, wireless clients will receive DHCP from whichever client on the network (linux MCE?) that's supplying that information. When you turn off DHCP on the wireless router, it simply routes packets between the WAN, LAN, and WLAN ports as necessary. If you plug the wireless router into your network without using the WAN side and disable DHCP then it will function essentially as an access point only. I've yet to encounter a device that does not allow this.
Title: Re: Single NIC installation
Post by: Zaerc on September 07, 2007, 09:21:34 am
OK - so you are saying that if a wireless access point is the external router (with say an internal subnet of 192.168.1.0/24) with DHCP services turned off and the LMCE server is an internal router with an external IP set manually to say 192.168.1.100 and an internal IP range of 192.168.81.0/24 and that DHCP services on LMCE is configured to give IP's in the range of (for example) 192.168.81.5-192.168.81.250 then when a wireless device connects to the network the wireless router will forward the request out to it's internal network (here I agree) and the LMCE box will respond with an IP address ?  Isn't that IP address going to be in the 192.168.81.0/24 range and hence not function correctly ?

Maybe there is an option for the DHCP to also handle ranges on its external card but I do not see it in the configuration options on the Admin website.  Maybe it does it by default without giving any configuration option (outside of file editing) ?  That would be rather rude - but I am sure that is not the case because the installation procedures suggest you leave the DHCP turned on on your original router.

I know that you could turn the wireless router into an AP and make the LMCE your external router but if it ain't broke why fix it - especially if you are just trying LMCE to see if it fits your needs.  I still say that a 1 port configuration with DHCP services would suit everyone a lot better than this mechanism.  Most people who are going to try LMCE are going to have an infrastructure in place and switching off their existing DHCP service is a lot easier than what you have to go through to make this work (given that we have existing firewall rules etc on our existing router to make our applications work).


So basicly you're saying that everything needs to be changed because some people have no idea what they are doing?  This "mechanism" suits me just fine so I honestly don't agree with that being a shortcoming in the design of LMCE at all.

If you want to use things in a way they weren't intended you're going to have to put in at least some extra effort, there is nothing new (or even specific to LMCE) about that...
Title: Re: Single NIC installation
Post by: bobpaul on September 09, 2007, 01:25:17 pm
OK - so you are saying that if a wireless access point is the external router (with say an internal subnet of 192.168.1.0/24) with DHCP services turned off and the LMCE server is an internal router with an external IP set manually to say 192.168.1.100 and an internal IP range of 192.168.81.0/24 and that DHCP services on LMCE is configured to give IP's in the range of (for example) 192.168.81.5-192.168.81.250 then when a wireless device connects to the network the wireless router will forward the request out to it's internal network (here I agree) and the LMCE box will respond with an IP address ?  Isn't that IP address going to be in the 192.168.81.0/24 range and hence not function correctly ?

No. I was replying to someone who stated that you couldn't use a wireless router and do a 2 nic installation of LinuxMCE. That is, you have your cable modem plugged into LinuxMCE and another NIC on linux MCE running to a LAN port on your router. This works fine provided you have DHCP turned off on the router.

If you really want to do a single NIC installation of LinuxMCE, please see the other posts I made in this thread where I describe the configuration necessary to have an external wireless router but DHCP handled by a single NIC LinuxMCE rather than the router. I completely agree this is not straight forward enough and should be supported by the installer.

The point of my comment is that wireless routers can be used quite simply with LinuxMCE, esp if you use LinuxMCE in a 2+nic configuration as your primary router. Wireless is by no means incompatible.
Title: Re: Single NIC installation
Post by: Zaerc on September 09, 2007, 03:14:07 pm
I completely agree this is not straight forward enough and should be supported by the installer.

No it shouldn't.  The intended way to set it up is with 2 network cards.  I see no need at all to change the installer merely because the proper setup doesn't suit a few people that are only interested in half the features.
Title: Re: Single NIC installation
Post by: bobpaul on September 09, 2007, 07:39:26 pm
No it shouldn't.  The intended way to set it up is with 2 network cards.  I see no need at all to change the installer merely because the proper setup doesn't suit a few people that are only interested in half the features.

The promotional videos all make it sound like one can easily take advantage of all sorts of extra hardware if they happen to have it, but if they don't have it LinuxMCE will fallback gracefully with as much functionality as possible given the circumstances. I don't have two NICs, nor do I have any great intention of running a second drop to the living room. (I'm running a combined front/backend, which is a recommended configuration.) My choice is either to add a wireless link to the local network (so now I'll be quite bandwidth limited as far as stream to my other machines), run an unsightly cable across the floor and around the house, or go through the hassle of running a second cable through the walls. Nice.
Title: Re: Single NIC installation
Post by: Zaerc on September 09, 2007, 08:14:17 pm
Somehow I'm still not convinced, what was the exact "problem" again? 

Title: Re: Single NIC installation
Post by: dopey on September 10, 2007, 03:32:57 am
What I think Zarec is saying is the two NIC installation is at the very heart of LinuxMCE. Not having LinuxMCE as the DHCP router removes more functionality then most of the users are willing to except. Your argument that LinuxMCE is supposed to scale back gracefully is flawed. Lets say you didn't have a CPU, you just couldn't run LinuxMCE. There are some components that's just required, period.

Having said that, there are ways to have a single NIC installation and still have the core be the DHCP server with another router acting as the internet gateway. If anything should go in the install, it should be that. There is really no easy way to put that in a wizard though. You could certainly try...
Title: Re: Single NIC installation
Post by: Zaerc on September 10, 2007, 11:15:25 am
Maybe you should read this thread again, there are several people saying that construction works just fine but requires some extra setup.

I still see no deficiency in the installer at all.  Having to do some extra configuration simply because you chose not to follow the recommended setup is not really an argument. 
Title: Re: Single NIC installation
Post by: teedge77 on September 10, 2007, 03:42:05 pm
OK - so you are saying that if a wireless access point is the external router (with say an internal subnet of 192.168.1.0/24) with DHCP services turned off and the LMCE server is an internal router with an external IP set manually to say 192.168.1.100 and an internal IP range of 192.168.81.0/24 and that DHCP services on LMCE is configured to give IP's in the range of (for example) 192.168.81.5-192.168.81.250 then when a wireless device connects to the network the wireless router will forward the request out to it's internal network (here I agree) and the LMCE box will respond with an IP address ?  Isn't that IP address going to be in the 192.168.81.0/24 range and hence not function correctly ?
Quote


its not even necessary to have it on a separate subnet. all my stuff is on the 192.168.1.X and with one NIC. It just shows up as

eth0:192.168.1.215
eth0:0 192.168.1.63

why is that so hard? theres no difficulty whatsoever in making a single NIC installation. You're all putting way too much thought into it. Obviously it isnt a gateway with one NIC.....its not going to be doing any routing...why do you need separate subnets?? youll just have to ways to get to it...well....much more...dcerouter...localhost...the ips...and when it hands out dhcp ....its all on the same network as everything else. it takes two seconds in the webadmin to change it all and youre done.
Title: Re: Single NIC installation
Post by: totallymaxed on September 10, 2007, 06:20:18 pm
Maybe you should read this thread again, there are several people saying that construction works just fine but requires some extra setup.

I still see no deficiency in the installer at all.  Having to do some extra configuration simply because you chose not to follow the recommended setup is not really an argument. 


I agree. The lmce networking setup/options work as they are perfectly well for either a 2 NIC or single NIC config. Nothing in our opinion needs changing there. Most of our installations are single NIC installs but thats for the most part to allow us to build compact Core's without the need for adding a PCI card.

So once and for all ... you already have all the config options you need. Honest you really do!
Title: Re: Single NIC installation
Post by: dopey on September 11, 2007, 01:41:43 am
So once and for all ... you already have all the config options you need. Honest you really do!

This is what I meant by "it would be difficult to put that in a wizard". In order to do this completely and dummy proof it would also need to setup the external router as well as the core network config, which would change based on the external router config. Of course, if you know what you're doing or willing to read up on it (it's really not that hard) then the wizard is really unnecessary.
Title: Re: Single NIC installation
Post by: snowglyder on October 02, 2007, 10:00:55 pm
So I had this working at one time, and then I started over with 0704 DVD because I couldn't get the UI working in LMCE, and now I can't get the DHCP working on LMCE working again. IS it necessary to actually edit the config file? I don't remember having to do that last time...

I'm using a single NIC because I have DSL and the only real working phone line is in a guest bedroom upstairs (the other lines don't get a fast connection), and I want my hybrid system in the living room that's downstairs. I networked my house, with the wires going to a closet in my office, which is where my wireless router is. Here's my single NIC setup:

DSL modem -> WAN port on wireless router -> Gigabit Switch (to other ports in the house) -> Hybrid LMCE

I set it up with 192.168.1.2 external, and 192.168.1.10 as internal. Gateway is my wireless router as 192.168.1.1. I disabled DHCP on wireless router, and enabled on LMCE, but nothing is pulling an ip. Suggestions?
Title: Re: Single NIC installation
Post by: NikAmi on October 08, 2007, 07:19:13 pm
I don't like that you have to use LMCE as the DHCP server. I agree that it is necessary if you are running some crappy little SOHO firewall or switch, but if you are running something like a SmoothWall or IPCop, those boxes should handle the DHCP. I am going to be placing my APs on an orange or purple interface and have a captive portal force all unknown connections to a registration page. This forces me to use the SmoothWall as the DHCP server for at least the APs. What LMCE could do is create a simple addon module for these firewalls that fed the necessary PXE boot image and informed the LMCE core upon a DCHP acknowledge.
Title: Re: Single NIC installation
Post by: teedge77 on October 08, 2007, 07:42:42 pm
its for more than just pxe booting. it depends on what you have as far as hardware goes. just one example is voip. i use a cisco 7970 and it gets picked up by linuxmce. it then goes to asterisk and also gets an orbiter skin when linuxmce gives it an address.  what would the benefit be of having your firewall give dhcp over linuxmce or anything else?
Title: Re: Single NIC installation
Post by: mohansen on October 09, 2007, 07:58:40 am
Note:  I have not tried this yet.  I will be building a system in the next week or so and plan to test.  I agree that having LinuxMCE be the center of everything is probably the preference for many but is not something that works the best for me.

Is it not possible to have 2 separate home networks?  Leave your existing home network and then install LinuxMCE with 2 NIC's.  NIC #1, the outside/public side of LinuxMCE would be connected to your existing home network.  It would get an address via DHCP from your existing router or static.  NIC #2 would then be the NIC used for all the PXE boot and other LinuxMCE related functions that need LinuxMCE to provide DHCP services.  You would end up with a separate network for all the content distribution without compromising your current network.

This would end up being 2 routers running in series to your provider.

ISP ------  existing router -----home network----- LinuxMCE ------- LinuxMCE network
Title: Re: Single NIC installation
Post by: Zaerc on October 09, 2007, 05:42:48 pm
Note:  I have not tried this yet.  I will be building a system in the next week or so and plan to test.  I agree that having LinuxMCE be the center of everything is probably the preference for many but is not something that works the best for me.

Is it not possible to have 2 separate home networks?  Leave your existing home network and then install LinuxMCE with 2 NIC's.  NIC #1, the outside/public side of LinuxMCE would be connected to your existing home network.  It would get an address via DHCP from your existing router or static.  NIC #2 would then be the NIC used for all the PXE boot and other LinuxMCE related functions that need LinuxMCE to provide DHCP services.  You would end up with a separate network for all the content distribution without compromising your current network.

This would end up being 2 routers running in series to your provider.

ISP ------  existing router -----home network----- LinuxMCE ------- LinuxMCE network


That shouldn't be much of a problem.

However I have read somewhere that LMCE prioritzes VoiP and video streaming, with this kind of setup it won't be able to manage the bandwidth used up by the home-network.  This may or may not be important to you.  Another issue could be: accessing fileservers (for instance) located in your home-network,  setting this up will probably be a bit of a hassle.   


Title: Re: Single NIC installation
Post by: snowglyder on December 20, 2007, 09:48:02 pm
So I had this working at one time, and then I started over with 0704 DVD because I couldn't get the UI working in LMCE, and now I can't get the DHCP working on LMCE working again. IS it necessary to actually edit the config file? I don't remember having to do that last time...

I'm using a single NIC because I have DSL and the only real working phone line is in a guest bedroom upstairs (the other lines don't get a fast connection), and I want my hybrid system in the living room that's downstairs. I networked my house, with the wires going to a closet in my office, which is where my wireless router is. Here's my single NIC setup:

DSL modem -> WAN port on wireless router -> Gigabit Switch (to other ports in the house) -> Hybrid LMCE

I set it up with 192.168.1.2 external, and 192.168.1.10 as internal. Gateway is my wireless router as 192.168.1.1. I disabled DHCP on wireless router, and enabled on LMCE, but nothing is pulling an ip. Suggestions?

Still haven't got this to work. Anyone?
Title: Re: Single NIC installation
Post by: Matthew on December 21, 2007, 05:28:08 am
So I had this working at one time, and then I started over with 0704 DVD because I couldn't get the UI working in LMCE, and now I can't get the DHCP working on LMCE working again. IS it necessary to actually edit the config file? I don't remember having to do that last time...

I'm using a single NIC because I have DSL and the only real working phone line is in a guest bedroom upstairs (the other lines don't get a fast connection), and I want my hybrid system in the living room that's downstairs. I networked my house, with the wires going to a closet in my office, which is where my wireless router is. Here's my single NIC setup:

DSL modem -> WAN port on wireless router -> Gigabit Switch (to other ports in the house) -> Hybrid LMCE

I set it up with 192.168.1.2 external, and 192.168.1.10 as internal. Gateway is my wireless router as 192.168.1.1. I disabled DHCP on wireless router, and enabled on LMCE, but nothing is pulling an ip. Suggestions?

Still haven't got this to work. Anyone?

Have you looked at the "Single NIC" (http://wiki.linuxmce.org/index.php?title=DHCP_Plug_and_Play#Single_NIC_.26_Existing_DHCPd) wiki entry lately? It's been updated since after you had last posted in this thread.

FWIW, LMCE doesn't need to DHCP to the entire LAN, even if it's a double NIC setup. With 2 NICs, LMCE will get its outside LAN segment configs from your existing DHCPd. And serve DHCP, with its various net configs (eg. PXE boot, QoS firewall/router, etc) to its inside LAN segment (along with LMCE services like media redirection), with whichever devices dependent on those services you attach to it. So if you can attach any LMCE devices (or none) to the inside segment, then the LMCE Core itself can connect its outside segment to your existing LAN like any other device. You just can't put onto the outside segment any media directors or any other devices LMCE manages by UPnP.
Title: Re: Single NIC installation
Post by: Lowspirit on December 22, 2007, 04:23:24 pm
Im running a Linksys wireless router at fixed IP 192.168.1.1. I set it up with DHCP enabled, and distributing IP numbers between 192.168.1.2 and 192.168.1.120. The core (with a single NIC) is set up with fixed IP 192.168.1.8 internal and 192.168.1.9 external. The DHCP is activated here too, giving all pluto devices IP numbers ranged 192.168.1.121 - 192.168.1.140. The function of supplying IP numbers to non-pluto devicec is disabled. Now, when You add a new MD, it will be given a number within the pluto range. This setup work perfect for me running 3 MD's. All NAS and shared folders on the network is found by The core/MD correctly.
Title: Re: Single NIC installation
Post by: Matthew on December 22, 2007, 04:44:41 pm
Im running a Linksys wireless router at fixed IP 192.168.1.1. I set it up with DHCP enabled, and distributing IP numbers between 192.168.1.2 and 192.168.1.120. The core (with a single NIC) is set up with fixed IP 192.168.1.8 internal and 192.168.1.9 external. The DHCP is activated here too, giving all pluto devices IP numbers ranged 192.168.1.121 - 192.168.1.140. The function of supplying IP numbers to non-pluto devicec is disabled. Now, when You add a new MD, it will be given a number within the pluto range. This setup work perfect for me running 3 MD's. All NAS and shared folders on the network is found by The core/MD correctly.

What stops the LinkSys router DHCP from responding to "pluto devices" like the MDs when the MDs request DHCP service on 192.168.1.x? Don't both DHCPds (including the LinkSys and the Core) offer IP#s?
Title: Re: Single NIC installation
Post by: Lowspirit on December 22, 2007, 04:51:54 pm
I have no idea. It just works. One moment and i will access my router and see if it shows the MD's in the DHCP tables....

Nope. Can't see them there. I wonder why that is.. Anybody knows?

Title: Re: Single NIC installation
Post by: Matthew on December 22, 2007, 04:59:10 pm
I have no idea. It just works. One moment and i will access my router and see if it shows the MD's in the DHCP tables....

Nope. Can't see them there. I wonder why that is.. Anybody knows?

My guess is that you're just lucky, and in your particular installation your LMCE DHCPd answers first.

I think DHCP has a really serious design deficiency that multiple DHCPds on a single ethernet segment can't negotiate with each other to serve different requests. And that DHCP itself doesn't have an "include <URL>" directive to at least approximate that kind of server P2P cooperation. As soon as you add a smarter DHCPd to a segment, you depend on the dumb one to divulge its legacy configs and get out of the way properly at network redeployment time. Which shouldn't require any network engineering on anything but the new device. But now I'm just bitching in the wind.
Title: Re: Single NIC installation
Post by: Lowspirit on December 22, 2007, 05:05:02 pm
Come to think of it.. At the dawn of time (about 2 weeks ago) when  first found LMCE i ran DHCP on both core and Linksys. Every time i did that, the core got authority over the router, changing the IP's of all computers within the network from 192.168.1.xxx to 192.168.80.xxx. Every time. Does anybody know why this is? Why the core gets the first shot over the router?
Title: Re: Single NIC installation
Post by: joesd72 on December 23, 2007, 08:04:41 am
Come to think of it.. At the dawn of time (about 2 weeks ago) when  first found LMCE i ran DHCP on both core and Linksys. Every time i did that, the core got authority over the router, changing the IP's of all computers within the network from 192.168.1.xxx to 192.168.80.xxx. Every time. Does anybody know why this is? Why the core gets the first shot over the router?

When the Lease on the IPs are half way up they request new ones. I would assume that your core just responds to the request to renew with and IP sooner. So from my experance most store bought routers that server DHCP give a lease time of one day to three days (I think one is more common). So half way through the lease time (12 - 36 hr) the PCs sends out a request to renew that lease and the Core responds first.

Not that I commonly set up up two DHCP servers on the same net, but I have several times and one always seems to be more responsive for some reason and convert the network shortly. the only way around it would be limit the amount of available IPs, but that wouldn't guarantee what devices got IPs on what network.

**Feature Request within** another option would be let the DCE be the DHCP server and hack the DHCP config file to have it give out the router as the Gateway instead of itself (and obviously have them with the same IP scheme). it would be nice as a built in feature of the DHCP web configuration to manually define the gateway with out hacking the file as a way to dumb things down for the average user.

I think MCE is a great product, but we have to get some of this stuff more friendly to the average n00b or id10t user other wise they will stay in Bill Gates cult. I think a small network config script that they can ask if this will be the DHCP server AND the GateWay also might make that easier.

I'm personally onboard with the people that want a separate router for security reasons. I'd rather a separate router be out front to be hacked instead of a system that controls my whole house. I use IPCOP and can port forward what I need to make the features work if I know all the ports. I would accept using LMCE as my router also if the DHCP and firewall were more configurable (need my VPN specially). maybe someone can fork IPCOP and plug it in as LMCEs firewall.
Title: Re: Single NIC installation
Post by: Matthew on December 23, 2007, 05:53:33 pm
**Feature Request within** another option would be let the DCE be the DHCP server and hack the DHCP config file to have it give out the router as the Gateway instead of itself (and obviously have them with the same IP scheme). it would be nice as a built in feature of the DHCP web configuration to manually define the gateway with out hacking the file as a way to dumb things down for the average user.

I think MCE is a great product, but we have to get some of this stuff more friendly to the average n00b or id10t user other wise they will stay in Bill Gates cult. I think a small network config script that they can ask if this will be the DHCP server AND the GateWay also might make that easier.

I'm personally onboard with the people that want a separate router for security reasons. I'd rather a separate router be out front to be hacked instead of a system that controls my whole house. I use IPCOP and can port forward what I need to make the features work if I know all the ports. I would accept using LMCE as my router also if the DHCP and firewall were more configurable (need my VPN specially). maybe someone can fork IPCOP and plug it in as LMCEs firewall.

There are going to be two net topos for LMCE deployments: an entry level setup with no IP PNP net devices, often on a reused existing PC HW to try it out with just the existing single NIC, and an existing DHCP and router. With no IP PNP devices to support (excluding storage shares, which don't need LMCE DHCP), LMCE does not need to be the DHCP server. LMCE never really needs to be the router (even the 2-NIC default can sit behind a separate router on the outside LAN segment), though of course firewall features do require 2 NICs. When people want to support IP PNP devices, they can upgrade to a 2-NIC PC or install a second NIC, though some people will start with that full version.

So yes, the LMCE Network Settings page should expose the dhcpd.conf "routers" (and maybe even the "next-server" for hosting the bootfile outside the Core) option that's already in the file. The Wizard should offer a high-level switching option between the two scenarios, which the initial installer should also accept.

LMCE is supposed to serve a home audience, not (necessarily) a hacker audience. Even when pro installers are deploying at a customer's site, the time saved and mistakes avoided with such automation will lower costs. And of course nontech consumers will find that significant barrier to entry dropped. Which is the main benefit of using competitor products like Windows MCE: it's really simple, in usage terms that the mass market can easily understand.

You should request a UI feature in Mantis (http://mantis.linuxmce.org/bug_report_page.php) (Category: Webadmin / Severity: feature).
Title: Re: Single NIC installation
Post by: joesd72 on December 23, 2007, 07:37:17 pm

You should request a UI feature in Mantis (http://mantis.linuxmce.org/bug_report_page.php) (Category: Webadmin / Severity: feature).

Thanks Matthew. Feature properly requested. I think I'm starting to like you. You're smarter than me, or atleast you have better grammar.
Title: Re: Single NIC installation
Post by: Matthew on December 23, 2007, 08:36:31 pm

You should request a UI feature in Mantis (http://mantis.linuxmce.org/bug_report_page.php) (Category: Webadmin / Severity: feature).

Thanks Matthew. Feature properly requested. I think I'm starting to like you. You're smarter than me, or atleast you have better grammar.

Anything I can do grammatically to help :) ...
Title: Re: Single NIC installation
Post by: Zaerc on December 23, 2007, 08:44:13 pm
...
There are going to be two net topos for LMCE deployments: an entry level setup with no IP PNP net devices, often on a reused existing PC HW to try it out with just the existing single NIC, and an existing DHCP and router. With no IP PNP devices to support (excluding storage shares, which don't need LMCE DHCP), LMCE does not need to be the DHCP server. LMCE never really needs to be the router (even the 2-NIC default can sit behind a separate router on the outside LAN segment), though of course firewall features do require 2 NICs. When people want to support IP PNP devices, they can upgrade to a 2-NIC PC or install a second NIC, though some people will start with that full version.

So yes, the LMCE Network Settings page should expose the dhcpd.conf "routers" (and maybe even the "next-server" for hosting the bootfile outside the Core) option that's already in the file. The Wizard should offer a high-level switching option between the two scenarios, which the initial installer should also accept.

LMCE is supposed to serve a home audience, not (necessarily) a hacker audience. Even when pro installers are deploying at a customer's site, the time saved and mistakes avoided with such automation will lower costs. And of course nontech consumers will find that significant barrier to entry dropped. Which is the main benefit of using competitor products like Windows MCE: it's really simple, in usage terms that the mass market can easily understand.

You should request a UI feature in Mantis (http://mantis.linuxmce.org/bug_report_page.php) (Category: Webadmin / Severity: feature).
You are wrong, in many cases Linux MCE does need to be the router and the DHCP server.  This setup is there for a reason, that it does not suit you personally as the default scenario is a different problem. 

When people do not want all these features they can be turned off.  Furthermore LinuxMCE != WindowsMCE, try to remember that.
Title: Re: Single NIC installation
Post by: 1audio on December 24, 2007, 02:03:27 am
Networking issues are the biggest timesinks in many installations. Especially mixed installs with Linux, Win XP Win Vista and Mac systems sharing the network. If all of those systems behaved perfectly it would be more straightforward to make it all work. Add some other networked devices and getting them all to communicate is tough.

The other question is the performance hit from using the core to route through or directing to an external hardware router. And having separate nets or one net. I'm using a single NIC install, fixed IP to my external home gateway (Trendnet router) on 192.168.0.1 and DHCP to my internal network on 192.168.80.XXX. This allows me to point a machine that doesn't need to be part of the network to another address on the 0.XXX subnet and it still works even when the core is down. I can't see a performance problem with this arrangement and can pretty consistently get 10+ Mbps D/L speed from Comcast on the internal net. And the internal net is all Gigabit in which I get better than 300 Mbps throughput on the Windoze machines (Their usual limits). Am I missing something? I'm no network wiz.


I would like to see a simple UI accessable from the advanced screen allowing selection of the options available-
1 NIC
2 NIC's

Get core IP from DHCP on which NIC OR Set Fixed core IP on which NIC
Internal DHCP on /off
DHCP on which NIC (inside/ outside)
PPOE setup
VPN setup

Plus Firewall configuration with some help notes like which ports support which services in the system (With VOIP and remote access etc. there are a lot of details to sort out) Perhaps instructions on setting for an external router for ports DMZ etc. if relevant.

Add some error checking to make sure the configurations are valid.

I can add my perspective to the Mantis if its not too far off base.
Title: Re: Single NIC installation
Post by: colinjones on December 24, 2007, 03:13:10 am
On the point of lease renewals and 2 DHCP servers on the same physical segment...

This is *not* a design flaw of DHCP!! DHCP has no requirement to allow for 2 different DHCP servers serving different functions - serving the same function, certainly, ie providing redundancy - this is in fact a very common configuration on larger networks. Usually with a local DHCP server and a redundant, centralised, remote DHCP server backing it up. It is very easy to configure - all the same scope options except each has only a part of the complete subnet range, not overlapping. This way they collaborate perfectly well, and do not conflict. If one fails, the other can take over seemlessly - just the router needs its DHCPHelper option set so clients can reach the remote DHCP server.

The fly in the ointment here is that both DHCP servers are not serving the same function, LMCE uses DHCP for much more than assigning IP addresses, so this type of configuration doesn't work for us. This isn't a reflection on the design of DHCP!!! It is fine, we are just trying to use it for something very specific which it wasn't designed for.

Also - yes, you can add/extend the DHCP schema however you want, it is already Very large and I would be surprised if you couldn't find a scope option to suit by default, to pass out any info you wanted.

With Lowspirits config, no there is nothing to prevent the real router providing the leases - and it is probably true that it was just luck that nas's, etc were served by the core. As for MDs, they are looking for PXE scope options, so probably ignore the real router's offers because they don't contain them. Both DHCP servers will respond with an offer, it is then up to the client which it chooses. The only way around this would be a packet filter on the real router (tried this on mine, didn't work!) or an ACL on the switch ports (probably requires a layer 3 switch in most cases!)

But once the devices have been "lucky" the first time, the reason this continues has nothing to do with the lease expiration times or the half lease renewal requests. DHCP clients remember their server they received after the first broadcast, and when requesting renewal of a lease direct it straight to that server, not broadcast. So as long as that server stays responsive, they will always get their renewals from it not the real router, and the IP address will remain the same.

On that note - the core also remembers where a device was in its DHCP config file. And will allow a lease to be renewed at the same IP address EVEN IF that IP address is not in the configured subnet scope! This caused me a lot of pain trying to work out why my Windows PC share media was no longer available. Briefly I turned on my router DHCP server and it got an IP address from it, outside the core's DHCP range. I then turned it off again and got my PC to renew again. As it couldn't find the router DHCP server any more it went back to broadcasting and the core responded. But it seems that the PC didn't only broadcast for a new lease, it requested a renewal of the existing IP address. Even though this was outside the core's scope, because it was in the config file it allowed it to keep that address!! No amount of releasing and renewing or rebooting would stop this because even then, the core's DHCP server still remembered this IP and kept giving it out.

Because it is outside the correct range, the core just didn't seem to want to "see" that share and its media any more. I had to manually remove the entry from DHCP3 server's conf file and release/renew - then it got a valid IP in the range and presto the media was back.

I am turning on and off my router's DHCP server regularly as I test my core in VM, so if anybody else is doing this, beware of stray leases screwing up things like this. Because I can't run the VM all the time, I can't switch over permanently to LMCE as DHCP, but once I set up a proper physical core, that's what I will be doing!
Title: Re: Single NIC installation
Post by: Matthew on December 26, 2007, 11:14:06 pm
On the point of lease renewals and 2 DHCP servers on the same physical segment...

This is *not* a design flaw of DHCP!! DHCP has no requirement to allow for 2 different DHCP servers serving different functions - serving the same function, certainly, ie providing redundancy - this is in fact a very common configuration on larger networks. Usually with a local DHCP server and a redundant, centralised, remote DHCP server backing it up. It is very easy to configure - all the same scope options except each has only a part of the complete subnet range, not overlapping. This way they collaborate perfectly well, and do not conflict. If one fails, the other can take over seemlessly - just the router needs its DHCPHelper option set so clients can reach the remote DHCP server.

The fly in the ointment here is that both DHCP servers are not serving the same function, LMCE uses DHCP for much more than assigning IP addresses, so this type of configuration doesn't work for us. This isn't a reflection on the design of DHCP!!! It is fine, we are just trying to use it for something very specific which it wasn't designed for.

Also - yes, you can add/extend the DHCP schema however you want, it is already Very large and I would be surprised if you couldn't find a scope option to suit by default, to pass out any info you wanted.

With Lowspirits config, no there is nothing to prevent the real router providing the leases - and it is probably true that it was just luck that nas's, etc were served by the core. As for MDs, they are looking for PXE scope options, so probably ignore the real router's offers because they don't contain them. Both DHCP servers will respond with an offer, it is then up to the client which it chooses. The only way around this would be a packet filter on the real router (tried this on mine, didn't work!) or an ACL on the switch ports (probably requires a layer 3 switch in most cases!)

But once the devices have been "lucky" the first time, the reason this continues has nothing to do with the lease expiration times or the half lease renewal requests. DHCP clients remember their server they received after the first broadcast, and when requesting renewal of a lease direct it straight to that server, not broadcast. So as long as that server stays responsive, they will always get their renewals from it not the real router, and the IP address will remain the same.

On that note - the core also remembers where a device was in its DHCP config file. And will allow a lease to be renewed at the same IP address EVEN IF that IP address is not in the configured subnet scope! This caused me a lot of pain trying to work out why my Windows PC share media was no longer available. Briefly I turned on my router DHCP server and it got an IP address from it, outside the core's DHCP range. I then turned it off again and got my PC to renew again. As it couldn't find the router DHCP server any more it went back to broadcasting and the core responded. But it seems that the PC didn't only broadcast for a new lease, it requested a renewal of the existing IP address. Even though this was outside the core's scope, because it was in the config file it allowed it to keep that address!! No amount of releasing and renewing or rebooting would stop this because even then, the core's DHCP server still remembered this IP and kept giving it out.

Because it is outside the correct range, the core just didn't seem to want to "see" that share and its media any more. I had to manually remove the entry from DHCP3 server's conf file and release/renew - then it got a valid IP in the range and presto the media was back.

I am turning on and off my router's DHCP server regularly as I test my core in VM, so if anybody else is doing this, beware of stray leases screwing up things like this. Because I can't run the VM all the time, I can't switch over permanently to LMCE as DHCP, but once I set up a proper physical core, that's what I will be doing!

What is missing from the design of the standard DHCP protocol is precisely what is a problem for LMCE when there is an existing DHCP server on a LAN into which LMCE is installed. The existing DHCPd must be turned off, or the LMCE DHCPd must be turned off, because there can be only a single DHCP option set served to a single LAN segment. For redundancy DHCP does have failover directives as a rudimentary interserver protocol, but work on fuller DHCP interserver operations (http://www.google.com/search?q=dhcp+interserver) has not been completed. That is indeed a design flaw, that various people have done some work to correct for over 10 years, though it's not been fixed yet. Largely because failover support has met the needs of the most demanding networks so far. But the recent emergence of UPnP over LANs shows where the current DHCP design is missing that important functionality. But in the meantime if we want LMCE to work with a single NIC, we need to make LMCE work in that environment without DHCP itself supporting that setup.

Starting to use LMCE with a single-NIC machine is going to continue to be a popular option, increasingly so as more people want to try it out without supporting other devices than a simple hybrid, then switch later when they see it's other benefits. And also in general as an appliance. So I'm exploring it, and posting my results.

If other people's own personal preferences don't include that configuration, they're welcome to ignore the efforts, and spend their valuable time doing something else instead that does interest them.
Title: My Single NIC installation
Post by: Tunkkaamo on January 03, 2008, 08:55:13 am
Here's my single NIC setup:

DSL modem -> WAN port on wireless router -> Gigabit Switch (to other ports in the house) -> Hybrid LMCE

I set it up with 192.168.1.2 external, and 192.168.1.10 as internal. Gateway is my wireless router as 192.168.1.1. I disabled DHCP on wireless router, and enabled on LMCE, but nothing is pulling an ip. Suggestions?

Thanks Snowglyder: I am a bit of a newbie on LMCE still, but I got my installation working Ok with your instructions.
While there are many reasons for people wanting to use a single NIC and Core not as a router mine are the following:

-My core is not allways on, since the whole installation is for my own testing purposes only.
-Keeping the core on all the time would waste a lot of energy (electricity bill has gone up 130% during this decade where I live and also we must remember the environment and not waste energy in wain)
-I have a perfectly vell working switch/router/DHCP/Firewall device before my DSL box, which requires zero maintenance.

Now my system is the following: Zyxel Lan switch/firewall with gateway ip 192.168.1.1, DHCP off and the WAN port to the DSL modem.
Core has DHCP on and external ip 192.168.1.2, internal ip 192.168.1.3 and with single NIC.
DCHP is set up to give ip:s from 192.168.1.5 - 192.168.1.30.

Normal computers, while not booting from Core and acting as Media Directors, have static ip:s from 192.168.1.31 up and with gateway and DNS of  192.168.1.1  .

Works, no probs: I can use my computers as normal workstations and when I want them to act as Media Directors I just boot them from the network....




Title: Re: Single NIC installation
Post by: 1audio on January 06, 2008, 08:51:44 am
It looks like your core could end up booting off of itself. The internal and external NIC's are on the same subnet. It should work and it similar  to what I have done. But the usual practice is to keep the internal net on the 192.168.80.X so it won't get mixed up with the external net. I'm doing this through a single NIC with no problems. If I need a PC to go around the system I put it on the same net as the router with a fixed IP (and set up windoze networking with a fallback fixed IP on that net).
Title: Re: Single NIC installation
Post by: snowglyder on January 10, 2008, 05:12:44 pm
....
DHCP clients remember their server they received after the first broadcast, and when requesting renewal of a lease direct it straight to that server, not broadcast. So as long as that server stays responsive, they will always get their renewals from it not the real router, and the IP address will remain the same.

On that note - the core also remembers where a device was in its DHCP config file. And will allow a lease to be renewed at the same IP address EVEN IF that IP address is not in the configured subnet scope! This caused me a lot of pain trying to work out why my Windows PC share media was no longer available. Briefly I turned on my router DHCP server and it got an IP address from it, outside the core's DHCP range. I then turned it off again and got my PC to renew again. As it couldn't find the router DHCP server any more it went back to broadcasting and the core responded. But it seems that the PC didn't only broadcast for a new lease, it requested a renewal of the existing IP address. Even though this was outside the core's scope, because it was in the config file it allowed it to keep that address!! No amount of releasing and renewing or rebooting would stop this because even then, the core's DHCP server still remembered this IP and kept giving it out.

Because it is outside the correct range, the core just didn't seem to want to "see" that share and its media any more. I had to manually remove the entry from DHCP3 server's conf file and release/renew - then it got a valid IP in the range and presto the media was back.
....

Interesting. I haven't been able to get my Core to give out IP's, and this seems like what might have happened to my setup. I'm going to check the conf file and see if I can't get this thing straightened out! I still don't have LMCE working correctly because of this DHCP problem and lack of time to figure it out, but now I have something to try! Thanks again!
Title: Re: My Single NIC installation
Post by: snowglyder on January 10, 2008, 05:21:38 pm

Thanks Snowglyder: I am a bit of a newbie on LMCE still, but I got my installation working Ok with your instructions.
While there are many reasons for people wanting to use a single NIC and Core not as a router mine are the following:

-My core is not allways on, since the whole installation is for my own testing purposes only.

....


I'm glad my setup helped you! It's funny that I have it setup correctly, but DHCP stopped working and the core isn't seeing my media. Colinjones had a seemingly good explanation, so hopefully I can get it up and working again...