Route Question

From: Dan Bent (dbent_at_benefit-systems.com)
Date: 01/30/04


Date: 30 Jan 2004 00:50:29 -0800

I've got a problem I've never seen, and I'm not even sure where to ask
the question, or what information to provide, so bear with me. I have
a firewall running OpenBSD 3.4, and a web server running FreeBSD 4.9.
The firewall's internal interface ia 10.0.1.254. The web server is
10.0.1.251. I can ping and traceroute to the 10.0.1.251 box from
machines inside the firewall, and I get normally expected results
(quick pings, and a route directly to 10.0.1.251). However, when I
traceroute to 10.0.1.251 from the firewall (10.0.1.254), it seems to
get hung up trying to get there through the localhost.

$ traceroute 10.0.1.251
traceroute to 10.0.1.251 (10.0.1.251), 64 hops max, 40 byte packets
 1 localhost (127.0.0.1) 0.745 ms 0.618 ms 0.235 ms
 2 localhost (127.0.0.1) 0.620 ms 0.642 ms 0.400 ms
 3 localhost (127.0.0.1) 0.507 ms 0.735 ms 0.494 ms
 4 localhost (127.0.0.1) 0.614 ms 0.859 ms 0.402 ms
 5 localhost (127.0.0.1) 0.477 ms 0.947 ms 0.681 ms
 6 localhost (127.0.0.1) 0.767 ms 1.8 ms 0.857 ms
 7 localhost (127.0.0.1) 1.13 ms 1.142 ms 0.904 ms
 8 localhost (127.0.0.1) 0.974 ms 1.164 ms^C

Routing table on firewall looks like this:
$ route show
Routing tables

Internet:
Destination Gateway Flags
default 204.128.254.254 UG
10.0.1.0 link#2 U
10.0.1.1 0:60:b0:4a:79:eb UH
10.0.1.6 0:30:6e:13:b6:bc UH
10.0.1.19 2:7:1:1c:5c:32 UH
10.0.1.23 0:4:76:f2:82:89 UH
10.0.1.45 0:1:3:c4:81:0 UH
10.0.1.73 0:4:76:b7:1f:b5 UH
gate localhost UGH
10.0.1.254 0:40:ca:19:dc:84 UH
127.0.0.0 localhost UG
localhost localhost UH
204.128.254.128 link#1 U
www 0:1:2:3b:8:47 UH
204.128.254.254 0:d0:58:a3:b2:b1 UH
BASE-ADDRESS.MCA localhost U

Why is that happening? Where should I look to correct it?
Thanks in advance.



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