Network problem

[Jeff Vian]

On Tue, 2005-02-22 at 20:23 +0100, Mats Erlandson wrote:
> The ifconfig output from 'problem' computer;
> eth0      Link encap:Ethernet  HWaddr 00:0F:EA:5C:06:CF
>           inet addr:192.168.0.90  Bcast:192.168.0.255  Mask:255.255.255.0
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:1194 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:399 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:304926 (297.7 KiB)  TX bytes:46169 (45.0 KiB)
>           Interrupt:209 Base address:0xc000
> 
> eth1      Link encap:Ethernet  HWaddr 00:50:BA:BA:02:C6
>           inet addr:192.168.0.91  Bcast:192.168.0.255  Mask:255.255.255.0
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:864 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:11 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:275934 (269.4 KiB)  TX bytes:812 (812.0 b)
>           Interrupt:169 Base address:0xb000
> 

You have 2 network cards with the same IP subnet.  In most cases this is
BAD.

Notice that in both the other machines you only have one functioning
interface.

Simple fix....   disconnect the cable from eth1 and reboot.


> and the output from 'netstat -rn';
> 
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  irtt 
> Iface
> 192.168.0.0     0.0.0.0         255.255.255.0   U         0 0          0 
> eth0
> 192.168.0.0     0.0.0.0         255.255.255.0   U         0 0          0 
> eth1
> 169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 
> eth1
> 0.0.0.0         192.168.0.1     0.0.0.0         UG        0 0          0 
> eth0
> 
> Now from working computer 1;
> 
> eth0      Link encap:Ethernet  HWaddr 00:0C:76:AC:69:37
>           inet addr:192.168.0.102  Bcast:192.168.0.255  Mask:255.255.255.0
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:171 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:88 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:32372 (31.6 KiB)  TX bytes:10635 (10.3 KiB)
> 
> 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:13064 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:13064 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:0
>           RX bytes:16189940 (15.4 MiB)  TX bytes:16189940 (15.4 MiB)
> 
> and
> 
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  irtt 
> Iface
> 192.168.0.0     0.0.0.0         255.255.255.0   U         0 0          0 
> eth0
> 169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 
> eth0
> 0.0.0.0         192.168.0.1     0.0.0.0         UG        0 0          0 
> eth0
> 
> And, from a third computer (working);
> 
> ath0      Link encap:Ethernet  HWaddr 00:40:05:26:42:3A
>           inet addr:192.168.0.103  Bcast:192.168.0.255  Mask:255.255.255.0
>           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
>           RX packets:206854 errors:180304 dropped:0 overruns:0 frame:180304
>           TX packets:141345 errors:1497 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:199
>           RX bytes:222052073 (211.7 MiB)  TX bytes:17587750 (16.7 MiB)
>           Interrupt:10 Memory:f8a40000-f8a50000
> 
> eth0      Link encap:Ethernet  HWaddr 00:00:39:2C:3D:C7
>           UP BROADCAST MULTICAST  MTU:1500  Metric:1
>           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:1000
>           RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
> 
> 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:3447 errors:0 dropped:0 overruns:0 frame:0
>           TX packets:3447 errors:0 dropped:0 overruns:0 carrier:0
>           collisions:0 txqueuelen:0
>           RX bytes:4227407 (4.0 MiB)  TX bytes:4227407 (4.0 MiB)
> 
> and
> 
> Kernel IP routing table
> Destination     Gateway         Genmask         Flags   MSS Window  irtt 
> Iface
> 192.168.0.0     0.0.0.0         255.255.255.0   U         0 0          0 
> ath0
> 169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 
> ath0
> 0.0.0.0         192.168.0.1     0.0.0.0         UG        0 0          0 
> ath0
> 
> Let me know if you want more information.
> 
> Regards,
> Mats
> 
> 
> Rick Stevens wrote:
> 
> > Mats Erlandson wrote:
> >
> >> I have just added another computer, having two network cards, to my 
> >> network.  The networking, I believe, is set up similarly to another 
> >> computer on the network.  The computers/devices on the network are 
> >> connected through a switch (DLink DI-624+).  The original computers 
> >> have no communications problems of any kind.  However, the newly 
> >> introduced computer cannot talk directly to the switch/gateway/DHCP 
> >> server but can access the other computers/devices on the local 
> >> network, unbelievably through the switch, nor can it access the 
> >> internet.
> >>
> >> Does anyone have a clue to where my problem is?
> >
> >
> > We'd need to see the output of "ifconfig -a" on all three, along with
> > the output of "netstat -rn" on all three.
> > ----------------------------------------------------------------------
> > - Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
> > - VitalStream, Inc.                       http://www.vitalstream.com -
> > -                                                                    -
> > -           Blech!  ACKth!  Ooop!  -- Bill the Cat (Outland)         -
> > ----------------------------------------------------------------------
> >
> >
>