Subject: cache forver in 3.2.0-rc2-00400-g866d43c ?

From: Arkadiusz Miśkiewicz <[email-masked]>
Date: Wed, 23 Nov 2011 19:10:37 +0100

Hello,

I'm using  my notebook in two different networks, suspending and resuming from 
ram between.

Network A (192.168.1.0/24) has server with IP 87.204.99.133 in the same lan. 
Now when I suspend, go to totally different network B (different provider, 
different lan, 192.168.0.0/24) and resume then I'm unable to connect to 
87.204.99.133.

Looks like network stack thinks that 87...133 is still directly reachable on 
eth1and I'm unable to make it forget that.

[root@t400 ~]# ip ne flush dev eth1; ip r flush table cache
[root@t400 ~]# ip r show table cache to 87.204.99.133
[root@t400 ~]# ping -c 1 87.204.99.133
PING 87.204.99.133 (87.204.99.133) 56(84) bytes of data.
From 192.168.0.5: icmp_seq=1 Destination Host Unreachable

--- 87.204.99.133 ping statistics ---
1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms

zsh: exit 1     ping -c 1 87.204.99.133
[root@t400 ~]# ip r show table cache to 87.204.99.133
87.204.99.133 dev eth1  src 192.168.0.5
    cache <redirected>  ipid 0x2838 rtt 17ms rttvar 12ms cwnd 10
87.204.99.133 from 192.168.0.5 dev eth1
    cache <redirected>  ipid 0x2838 rtt 17ms rttvar 12ms cwnd 10
[root@t400 ~]# ip ne show to 87.204.99.133
87.204.99.133 dev eth1  FAILED

tcpdump in meantime sees this:
19:06:26.907153 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 
87.204.99.133 tell 192.168.0.5, length 28
19:06:27.908379 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 
87.204.99.133 tell 192.168.0.5, length 28
19:06:28.907084 ARP, Ethernet (len 6), IPv4 (len 4), Request who-has 
87.204.99.133 tell 192.168.0.5, length 28
19:06:29.907145 IP (tos 0xc0, ttl 64, id 34465, offset 0, flags [none], proto 
ICMP (1), length 112)
    192.168.0.5 > 192.168.0.5: ICMP host 87.204.99.133 unreachable, length 92
        IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto ICMP (1), 
length 84)
    192.168.0.5 > 87.204.99.133: ICMP echo request, id 17590, seq 1, length 64

Any ideas?

Thanks,
-- 
Arkadiusz Miśkiewicz        PLD/Linux Team
arekm / maven.pl            http://ftp.pld-linux.org/