I use a a Debian testing (wheezy/sid) machine as a gateway for internet access. One interface (eth1) is connected to my lan and the other (eth0) is connected to an adsl router with ip masquerade enabled on the interface.

Since upgrading to Linux 3.0.0-1-686-pae yesterday I have seen strange results when machines on my lan perform a traceroute to the internet.

The address reported for the first hop is the traceroute target address, not the address of the eth1 interface on the linux machine as expected.

I have looked at packet traces with tcpdump and traceroute is reporting exactly what is on the wire.

I have changed no network settings on the gateway since installing the new kernel but am wondering if there is a new sysctl that should be applied.

for example - a traceroute to Yahoo from the lan has the first reply shown as coming from the yahoo IP address.

number9:~ bryan$ traceroute Yahoo! (not allowed domain name here)
traceroute: Warning: Yahoo! has multiple addresses; using 98.137.149.56
traceroute to any-fp3-real.wa1.b.yahoo.com (98.137.149.56), 64 hops max, 52 byte packets
1 ir1.fp.vip.sp2.yahoo.com (98.137.149.56) 0.547 ms 0.235 ms 0.160 ms
2 192.168.1.1 (192.168.1.1) 2.092 ms 0.896 ms 0.846 ms
3 akl-ip21-xdsl-gw.wxnz.net (182.154.0.21) 10.315 ms 12.763 ms 14.109 ms
4 as17435.cust.bdr01.akl02.akl.vocus.net.au (114.31.203.90) 15.822 ms 19.196 ms 9.592 ms
5 ten-0-3-0-120.bdr01.akl02.akl.vocus.net.au (114.31.203.89) 10.414 ms 9.725 ms 10.178 ms
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