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Old 07-27-2011, 03:07 PM   #1
bweaver
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my server can't ping other boxes on private network (192.168.0.0)


I run a server that is connected to several other boxes in a private network (192.168.0.0). I have had no problems previously, but upon a reinstall of Debian squeeze I have no connectivity to the private network: a ping of other addresses on that network fail. Ping and connection to outside world is fine. This box is configured similarly to another on this private network which connects successfully. I have quadruple-checked all my basic information. I post my ifconfig below of the malfunctioning device, then the ifconfig for equivalent nic on a box connected succesfully to the private network.

Questions:

1.Could it be a cable problem? (I don't see how since the cables have not been changed I do not believe since my reinstallation).

2. What about the difference in the last lines of eth1 below and eth2 of the successful box. Is it significant that the bad eth1 reads ...
Memory:fc3a0000-fc3c0000

while eth2 on the good box reads
Interrupt:16 Base address:0xef00



PHP Code:
eth0      Link encap:Ethernet  HWaddr 00:15:17:80:3f:c6  
          inet addr
:163.1.87.47  Bcast:163.1.87.255  Mask:255.255.254.0
          inet6 addr
fe80::215:17ff:fe80:3fc6/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU
:1500  Metric:1
          RX packets
:29414 errors:0 dropped:0 overruns:0 frame:0
          TX packets
:1337 errors:0 dropped:0 overruns:0 carrier:0
          collisions
:0 txqueuelen:
          RX bytes
:2961653 (2.8 MiB)  TX bytes:196533 (191.9 KiB)

eth1      Link encap:Ethernet  HWaddr 00:15:17:80:3f:c7  
          inet addr
:192.168.0.41  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr
fe80::215:17ff:fe80:3fc7/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU
:1500  Metric:1
          RX packets
:20301 errors:0 dropped:0 overruns:0 frame:0
          TX packets
:394 errors:0 dropped:0 overruns:0 carrier:0
          collisions
:0 txqueuelen:1000 
          RX bytes
:2096915 (1.9 MiB)  TX bytes:17268 (16.8 KiB)
          
Memory:fc3a0000-fc3c0000 

lo        Link encap
:Local Loopback  
          inet addr
:127.0.0.1  Mask:255.0.0.0
          inet6 addr
: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU
:16436  Metric:1
          RX packets
:383 errors:0 dropped:0 overruns:0 frame:0
          TX packets
:383 errors:0 dropped:0 overruns:0 carrier:0
          collisions
:0 txqueuelen:
          RX bytes
:42488 (41.4 KiB)  TX bytes:42488 (41.4 KiB
and on the good box:

PHP Code:
eth2      Link encap:Ethernet  HWaddr 00:48:54:51:0f:04  
          inet addr
:192.168.0.51  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr
fe80::248:54ff:fe51:f04/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU
:1500  Metric:1
          RX packets
:65 errors:0 dropped:0 overruns:0 frame:0
          TX packets
:12 errors:0 dropped:0 overruns:0 carrier:0
          collisions
:0 txqueuelen:1000 
          RX bytes
:12709 (12.4 KiB)  TX bytes:980 (980.0 B)
          
Interrupt:16 Base address:0xef00 

Last edited by bweaver; 07-27-2011 at 03:08 PM.
 
Old 07-27-2011, 03:26 PM   #2
T3RM1NVT0R
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Hi there,

It could be a cable problem. Did you try pinging the problematic machine from a working machine?

For the second point that you have raised. Please let us know the output of following commands:

1. lspci | grep net
2. cat /proc/interrupts
 
Old 07-27-2011, 04:25 PM   #3
SL00b
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I suspect a routing problem, because you've got eth0 facing the public, and eth1 facing the internal network, and you're working just fine through the public interface. I suspect that works because the default route is pointing to the public interface.

Check your route table with the route command, and use route add if there's nothing there for the private network.
 
Old 07-27-2011, 04:37 PM   #4
Grejeru
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Quote:
Originally Posted by SL00b View Post
I suspect a routing problem, because you've got eth0 facing the public, and eth1 facing the internal network, and you're working just fine through the public interface. I suspect that works because the default route is pointing to the public interface.

Check your route table with the route command, and use route add if there's nothing there for the private network.
As SL00b suggested please show output of commands:
# ip r s
# ip a s
# netstat -rn
 
Old 07-28-2011, 10:38 AM   #5
bweaver
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thanks

It turned out to be a cable problem. But these commands you all suggested will be very useful to me. They give me output I was looking for on this and on other problems.
Thanks again!
 
Old 07-28-2011, 04:20 PM   #6
T3RM1NVT0R
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Glad, you got it sorted. Could you please mark this thread as solved.
 
  


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