DHCP server not issuing an IP Address !!!

[ibexcentral]

Hi,

I have installed from DVD onto a PC has one NIC. I have the PC connected to a switch and a laptop also connected to the switch no ADSL router in sight 

The core allocates an IP address internal 192.168.80.1 with external 192.168.80.254.

I have my laptop, running windows XP to obtain a DHCP address supposedly from the core but it does not. If I manually allocate 192.168.80.5 to my laptop it allows me to connect to the Admin webpage.

I want to PXE boot my laptop but if DHCP is not working on the core what chance have I got?

I have installed and reinstalled about 4 times now.

HELP !!!!!

Incidentally is there any way from the DVD install to only install Core not Media Director also?

Thanks

[Matthew]

Search the wiki for DHCP for your DHCP problems.

[ibexcentral]

I wouldn't have posted this if I had found anything on DHCP not working.

I cannot connect with static IP on PC but when I put that magic little dot in the circle next to obtain IP from DHCP the CORE doesn't seem to work.

Is there any way to see if DHCP is working or Not?

[Hagen]

You could try to 'repair network connection' in XP?
I have not seen this problem you describe ever, so sorry if this was not very helpful.

[pixelator]

Hi,

I have installed from DVD onto a PC has one NIC. I have the PC connected to a switch and a laptop also connected to the switch no ADSL router in sight 

The core allocates an IP address internal 192.168.80.1 with external 192.168.80.254.

I have my laptop, running windows XP to obtain a DHCP address supposedly from the core but it does not. If I manually allocate 192.168.80.5 to my laptop it allows me to connect to the Admin webpage.

I want to PXE boot my laptop but if DHCP is not working on the core what chance have I got?

I have installed and reinstalled about 4 times now.

HELP !!!!!

Incidentally is there any way from the DVD install to only install Core not Media Director also?

Thanks

One thing you could try is to change the external ip to a static ip on a different subnet. something like 192.168.81.1 and set a static for the internal ip for the core to 192.168.80.1

The external and internal should not share the same subnet.

[Zaerc]

I think I know what's going wrong here, what IP addresses do your modem and/or switch have?  (whatever is connected directly to your LMCE box).

[marrandy]

"Hi,

I have installed from DVD onto a PC has one NIC. I have the PC connected to a switch and a laptop also connected to the switch no ADSL router in sight  Smiley

The core allocates an IP address internal 192.168.80.1 with external 192.168.80.254.

I have my laptop, running windows XP to obtain a DHCP address supposedly from the core but it does not. If I manually allocate 192.168.80.5 to my laptop it allows me to connect to the Admin webpage.

I want to PXE boot my laptop but if DHCP is not working on the core what chance have I got?"



You need Two NIC's in the PC if you want linuxmce to work properly (aka the way it was designed).

The 192.168.80.254 is a default bogus as there is no external NIC.

No ADSL router in sight, but you mentioned ADSL router.  How do you get to the internet ?

Let's start over...to use linuxmce to it's full potential you need internet access and Two NIC's in the core (it will be limited otherwise)

To the internet, you have some sort of modem/router in a bridge, NAT, FW or combination thereof.  Unless you have paid for static you have a DHCP assigned IP address to your connection from you provider. In your case, you have a laptop so connect it directly to the modem, with the appropriate cable, set the laptop to dhcp client request and do a ifconfig -a or windoze ipconfig /all...what's the IP address assigned ?
It will be either, public IP or a private address IP typically 192.168.1.x which is a NAT'd router typically with a firewall.
Add the second NIC and connect it to the modem.  Connect the original NIC to the switch.  Reboot and check the reported settings again from linuxmce (an external of 192.168.1.x and internal 192.168.80.1)  you should be able to pull up google and youtube video under advanced - computing I think (not at my linuxmce test server I'm afraid)

Adding you laptop back on the switch and rebooting should give you a 192.168.80.x address

Reboot any other DHCP client systems and reset the static IP's to the 192.168.80.x range.

It's a lot simpler this way plus you have (depending on your ADSL box) a primary FW and a secondary linuxmce FW so if the primary is cracked, you have the secondary hopefully on a different code base.

[Matthew]

You can run LMCE with a single NIC, as explained in the wiki's DHCP entry section on "Single NIC".

What this setup requires is that LMCE run as the only DHCP server on the network, which means that if your switch, or any other device on your network, is assigning IP#s by running a DHCP server, then that old server has to be switched off. There probably is one running, or else how would your notebook have gotten its old IP#? If it got it by manual assignment, then you have to either continue manually assigning an IP# on the subnet that the LMCE DHCP server is on and assigning in, or you have to set the notebook to get its IP# by DHCP. Which is a first step to getting the notebook to boot by PXEboot anyway.

Then you have to make sure any other machine connecting to the LMCE server is also set to get its IP# by DHCP, or is manually set to a number on the LMCE subnet. You make them all on the same subnet by looking at the IP# that LMCE is assigning itself (in its Network Settings, but default is 192.168.80.1) and manually assigning numbers in that subnet to the other machine, or setting the LMCE DHCP server to assign IP#s on the other machines' subnet (and excluding those other machines IP#s from the range assignable by LMCE, to avoid conflicts) or by setting the other machines to use DHCP, which lets LMCE assign their IP#. Pick the method for each machine, including LMCE, that lets them all share the same subnet. Often routers/gateways (like cablemodems etc) don't allow using a DHCP client to set their internal LAN IP#, but either assign themselves one from their own internal DHCP server, or let you set them manually. Since that internal DHCP server must be turned off, you'd have to set it manually.

There are more details on working around bugs in LMCE DHCP configuration included in that DHCP wiki page.

Please return the favor of all this help by letting us know how it goes for you. If it still doesn't work, and this is a new case, we can fix it and document the scenario for the next person to encounter it.

[marrandy]

Matthew said :-

You can run LMCE with a single NIC, as explained in the wiki's DHCP entry section on "Single NIC".


Yes, that's why I said on my first line...

"You need Two NIC's in the PC if you want linuxmce to work properly (aka the way it was designed)."

ie. instead of just making sure you have the cables in the correct NIC's (in most cases), if you have one NIC you have to:-

1)   Turn off DHCP in your modem/NAT Router (as they usually come turned on by default)
2)   Assign a static IP to Linuxmce

Which is beyond most newbies as evidenced from the repeated questions in the forums.

You also lose the FW plus bandwidth control ie. think priority on the network for VOIP and video.

For the sake of a $20 or less gigabit ethernet card (or less for 100Mb) and all the hassle and loss, I don't think it's worth it, but go  knock yourself out. YMMV (Your Mileage May Vary).

[Zaerc]

Indeed, it's just not worth saving the $5 or so on an 100mbit PCI nic unless you know what you're doing.

[Matthew]

Matthew said :-

You can run LMCE with a single NIC, as explained in the wiki's DHCP entry section on "Single NIC".


Yes, that's why I said on my first line...

"You need Two NIC's in the PC if you want linuxmce to work properly (aka the way it was designed)."

ie. instead of just making sure you have the cables in the correct NIC's (in most cases), if you have one NIC you have to:-

1)   Turn off DHCP in your modem/NAT Router (as they usually come turned on by default)
2)   Assign a static IP to Linuxmce

Which is beyond most newbies as evidenced from the repeated questions in the forums.

You also lose the FW plus bandwidth control ie. think priority on the network for VOIP and video.

For the sake of a $20 or less gigabit ethernet card (or less for 100Mb) and all the hassle and loss, I don't think it's worth it, but go  knock yourself out. YMMV (Your Mileage May Vary).

It's not the $20 for the card that matters. It's the ability to use an existing PC without any HW work at all to try out LMCE casually. Especially if one is making a nondedicated core, or dualbooting, or using an old notebook, or just casually trying it out, just installing the SW and making some configs is going to appeal to a lot of people, some of whom will like it enough to get serious. Which is how successful projects grow: lower the barriers to entry while offering organized instructions for doing it right. Which means keeping the docs (like the wiki) current with those uses, rather than just leave people twisting in the wind in unanswered (or crankily answered) forum posts.

[teedge77]

a large selling point of lmce is supposed to be allowing nontechnical or mildly technical people to set this all up. installing new network cards, switches and routers isnt always as easy for them as pluggin in one cable. i know it takes a lot of work now to get a single nic going and obviously thats just as bad of a hurdle. maybe that will (should) get fixed one day to make it a little easier. it has been suggested before.

[Zaerc]

Well if you want easy... http://fiire.com/

[teedge77]

sorry...for the nontechinical reader ill repeat myself

a large selling point of lmce is supposed to be allowing nontechnical or mildly technical people to set this all up.

thats where the constant "plug n play" stuff comes from. its supposed to be easy to get it ALL set up. a single NIC install makes it easier for someone who doesnt know how to put in a switch or cant figure out how plugging two cables from the same computer into the dsl/wireless router they have now works and what they have to do. theres no reason it cant be made to allow a single nic install.

[Zaerc]

There's nothing stopping anyone from doing a single nic install.

However the recommended setup is with 2 NICs so that the nontechnical or mildly technical people can set this all up.

As with most things in life, you can't really have it both ways.