| View previous topic :: View next topic |
| Author |
Message |
kikibobo
n00b
Joined: 02 Feb 2004
Posts: 42
Location: Dublin
|
 Posted: Sun Jul 02, 2006 7:46 am Post subject: strange networking problem -- ICMP? UDP? [SOLVED] |
 |
|
Hi,
I just went through the somewhat tortuous recent "emerge -uDpvN world" experience. Among other things, this broke whatever I was doing with bind, so I switch to dnsmasq and ditched bind and dhcp.
I noticed that ntp was failing on one of two more or less identical servers. Looking a little deeper I found that one the all machines in my lan, ping works fine internally, but on one machine, I cannot ping anything outside the firewall. This is a straightforward home network behind a firewall/router/pppoe dsl modem. I can't for the life of me understand why I can ping other machines inside the firewall, but nothing outside the firewall, from just that machine.
Anyone have any suggestions on how to diagnose this?
Here's /sbin/ifconfig for a machine that's working normally (small MTU size is because this machine is hosting a mail server):
eth1 Link encap:Ethernet HWaddr 00:15:F2:35:31:14
inet addr:192.168.123.212 Bcast:192.168.123.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:576 Metric:1
RX packets:20812455 errors:0 dropped:0 overruns:0 frame:0
TX packets:16488010 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3291242167 (3138.7 Mb) TX bytes:16074051421 (15329.4 Mb)
Interrupt:193 Base address:0x6000
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:43346 errors:0 dropped:0 overruns:0 frame:0
TX packets:43346 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:12146970 (11.5 Mb) TX bytes:12146970 (11.5 Mb)
Here's for the machine that can't ping outside the firewall:
eth0 Link encap:Ethernet HWaddr 00:15:F2:66:99:1E
inet addr:192.168.123.210 Bcast:192.168.123.255 Mask:255.255.255.0
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:35268 errors:0 dropped:0 overruns:0 frame:0
TX packets:28302 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:16782768 (16.0 Mb) TX bytes:2795551 (2.6 Mb)
Interrupt:193 Base address:0x6000
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:4596 errors:0 dropped:0 overruns:0 frame:0
TX packets:4596 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1778737 (1.6 Mb) TX bytes:1778737 (1.6 Mb)
iptables is turned off.
Any help greatly appreciated....
Last edited by kikibobo on Mon Jul 03, 2006 6:08 am; edited 1 time in total |
|
| Back to top |
|
 |
nielchiano
Veteran
Joined: 11 Nov 2003
Posts: 1287
Location: 50N 3E
|
| Posted: Sun Jul 02, 2006 8:58 am Post subject: |
|
|
the only thing different between an internal ping and a ping to outside is that in the latter case, you need a "default gateway"
could you post on both machines? |
|
| Back to top |
|
|
kikibobo
n00b
Joined: 02 Feb 2004
Posts: 42
Location: Dublin
|
| Posted: Sun Jul 02, 2006 9:32 am Post subject: |
|
|
| nielchiano wrote: | the only thing different between an internal ping and a ping to outside is that in the latter case, you need a "default gateway"
could you post on both machines? |
Ah, that was it -- the switch to dnsmasq lost my gateway. Thanks! |
|
| Back to top |
|
|
nielchiano
Veteran
Joined: 11 Nov 2003
Posts: 1287
Location: 50N 3E
|
| Posted: Sun Jul 02, 2006 9:34 am Post subject: |
|
|
| kikibobo wrote: | | Ah, that was it -- the switch to dnsmasq lost my gateway. Thanks! |
No problem!
(don't forget to add [solved] to the topic subject) |
|
| Back to top |
|
|
|
Networking & Security
