Author Topic: core drops ssh, ping and webmin connections! why?  (Read 2392 times)

valent

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core drops ssh, ping and webmin connections! why?
« on: November 04, 2008, 10:22:15 pm »
Hi, I need to connect via ssh to my core but I cant. I tried pinging it and I get no reply. I have ktorrent running with web interface and can only connect it from core not from other laptop in my LAN. Why?

Core has two LAN cards;
eth0 - 10.10.1.1/24 that has nothing connected to it and has DHCP service ready to assing IP adreses
eth1 - 192.168.5.5 - the IP it how automatically from ADSL modem/router that it  is connected to.

I have other laptop (192.168.5.7) connected to same ADSL router but over over wireless.

When I ping laptop from core I get the response, when I ping core from the laptop I get no response.

I start ssh on core and on the laptop, and I can connect from core to laptop but I can't connect from laptop to core.

I tried deleting all iptables firewall rules with:
iptables --flush
iptables --table nat --flush
iptables --delete-chain
iptables --table nat --delete-chain

but I still can't ping or connect via ssh to core from my local LAN.

How can I fix this?

Cheers,
Valent.
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Zaerc

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Re: core drops ssh, ping and webmin connections! why?
« Reply #1 on: November 04, 2008, 11:18:48 pm »
Hi, I need to connect via ssh to my core but I cant. I tried pinging it and I get no reply. I have ktorrent running with web interface and can only connect it from core not from other laptop in my LAN. Why?

Core has two LAN cards;
eth0 - 10.10.1.1/24 that has nothing connected to it and has DHCP service ready to assing IP adreses
eth1 - 192.168.5.5 - the IP it how automatically from ADSL modem/router that it  is connected to.

I have other laptop (192.168.5.7) connected to same ADSL router but over over wireless.

When I ping laptop from core I get the response, when I ping core from the laptop I get no response.

I start ssh on core and on the laptop, and I can connect from core to laptop but I can't connect from laptop to core.

I tried deleting all iptables firewall rules with:
iptables --flush
iptables --table nat --flush
iptables --delete-chain
iptables --table nat --delete-chain

but I still can't ping or connect via ssh to core from my local LAN.

How can I fix this?

Cheers,
Valent.

Let's just say we're assuming that people by default do not want all their ports open to the world.  Which coincidentally, as it turns out, is usually a very bad idea to begin with.  I hope that clears the mystery up a bit.

web-admin > Advanced > Network > Firewall rules


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valent

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Re: core drops ssh, ping and webmin connections! why?
« Reply #2 on: November 05, 2008, 04:18:24 pm »
I found it myself 10 minutes after posting the question ;)
I know the security issue, but I'm behind a NAT and openning the firewall posts no security issue for me.

But I was puzzled why when I flushed manually iptables rules the firewall still functioned! How is that possible?
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valent

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Re: core drops ssh, ping and webmin connections! why?
« Reply #3 on: November 05, 2008, 10:21:16 pm »
Does LinuxMCE use some other mechanism other than iptables for firewall?

My understanding was if I flush all iptables rules it would be the same as turning it off from web interface. Why am I wrong?
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valent

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Re: core drops ssh, ping and webmin connections! why?
« Reply #4 on: November 08, 2008, 04:04:19 pm »
Is there some FAQ expaining what all is changed and why some things like iptables are chenged, how pluto software affects all other linux subsystems, etc...
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