Strange network behaviour (very strange!)

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mziccardi
Posts: 2
Joined: 2011/11/07 11:37:47

Strange network behaviour (very strange!)

Post by mziccardi » 2011/11/07 11:43:34

Hi all!

I'm having a really strange problem (and I'm desperate!): for some reason, everytime I reboot my server, the default gateway gets attached to the 'lo' interface, even if I correctly attached it to the eth0 device.

I fixed the problem editing the /etc/sysconfig/network file and adding

GATEWAY=195.75.145.1
GATEWAYDEV=eth0

however I'm not sure this is the solution: I already configured the default gateway only in the ifcfg-eth0 file!

After this, I have an even worse problem: doing an ssh 195.75.145.1, I get an answer from my own server like if it was a loopback address !

Here is the output of ifconfig:

eth0 Link encap:Ethernet HWaddr 5C:F3:FC:55:63:42
inet addr:195.75.145.122 Bcast:195.75.145.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:4281 errors:0 dropped:0 overruns:0 frame:0
TX packets:25 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4934949 (4.7 MiB) TX bytes:2133 (2.0 KiB)
Interrupt:28 Memory:92000000-92012800

eth2 Link encap:Ethernet HWaddr 00:1B:21:8E:0A:86
inet addr:192.168.19.95 Bcast:192.168.19.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2049 errors:0 dropped:0 overruns:0 frame:0
TX packets:917 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:236160 (230.6 KiB) TX bytes:99635 (97.2 KiB)
Memory:97d80000-97e00000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:56 errors:0 dropped:0 overruns:0 frame:0
TX packets:56 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:7714 (7.5 KiB) TX bytes:7714 (7.5 KiB)

lo:0 Link encap:Local Loopback
inet addr:195.75.145.120 Mask:255.255.255.0
UP LOOPBACK RUNNING MTU:16436 Metric:1

here is the output of ip route

192.168.19.0/24 dev eth2 proto kernel scope link src 192.168.19.95
195.75.145.0/24 dev eth0 proto kernel scope link src 195.75.145.122
169.254.0.0/16 dev eth0 scope link metric 1002
169.254.0.0/16 dev eth2 scope link metric 1004
default via 195.75.145.1 dev eth0

Please!! Do you have any advice?

Thanks,
Massimiliano

gerald_clark
Posts: 10642
Joined: 2005/08/05 15:19:54
Location: Northern Illinois, USA

Strange network behaviour (very strange!)

Post by gerald_clark » 2011/11/07 14:19:38

Why?
lo:0 Link encap:Local Loopback
inet addr:195.75.145.120 Mask:255.255.255.0
UP LOOPBACK RUNNING MTU:16436 Metric:1

mziccardi
Posts: 2
Joined: 2011/11/07 11:37:47

Re: Strange network behaviour (very strange!)

Post by mziccardi » 2011/11/07 17:10:38

I needed the lo:0 for local triangulation.

However, I solved the problem: it was the netmask.
Instead of 255.255.255.0 it must be 255.255.255.255.

Thank you!

Regards,
Massimiliano

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