Re: Can't access aliased ip address

[Jor-el <jorel@trillian.megadodo.umb>]

Chad,

On Wed, 2 Jan 2002, Chad Morgan wrote:

> 
> This doesn't appear to be the problem. When I ping ip address C, from
> machine A (my computer at a remote location) tcpdump icmp -i eth0 yields
> only a request.
> However, once I ping ip address B from Machine A it will show both the
> request and the reply.
> 
	This is puzzling. Your first sentence breaks my hypothesis and the
second sentence strengthens it. Perhaps if you could provide your routing
table more legibly, it would be of more help (use the -n option of route).
The hostnames in your prev. post were truncated and it was hard to guess
how the routing was setup.

	Also try the following : from B / C, do 
1.  traceroute A
2.  traceroute A -s C

	On A, monitor the traffic using a filter for src = A or dst = A
and post the results.

> Also, I just looked at the syslog, which I probably should've done earlier
> and found the following:
> 
> Jan  2 15:23:46 hostname kernel: Packet log: input DENY eth0 PROTO=1
> MACHINEA:8 IPADDRC:0 L=92 S=0x00 I=0 F=0x4000 T=43 (#9)
> 
	I dont know what this log entry means. Its possible that you have
a firewall problem but your symptoms are more indicative of a routing
problem. Perhaps the output of 'ipchains -L -v -n' would help (Note: I run
iptables and I'm guessing that its options are similar to ipchains. The -n
will produce numeric, rather than symbolic output).

Regards,
Jor-el