[radvd-devel-l] resetting ipv6-allrouters membership on eth6

[Ivan Skytte Jørgensen]

On Wednesday 28 April 2010 08:35:53 Pekka Savola wrote:
> There have been changes in this behaviour since radvd 1.1. It would be 
> helpful if you could test the latest radvd?

I tried 1.6, although I don't see what could have change there as a "diff radvd-1.1/device-linux.c radvd-1.6/device-linux.c" reports zero changes.

I started radvd-1.6 and it correctly joined the all-routers group on all relevant interfaces including eth6 and vlan60. I left it running for a day and everything was fine.

I then downed interface eth6 and upped it again. Then the problem appeared again:

soekris2:~ # cat /proc/net/igmp6 |fgrep eth6
8    eth6            ff020000000000000000000000000002     1 00000004 0
8    eth6            ff0200000000000000000001ff000000     3 00000004 0
8    eth6            ff0200000000000000000001ffca3c42     3 00000004 0
8    eth6            ff020000000000000000000000000001     1 0000000C 0
soekris2:~ # ifdown eth6
    eth6      is still used from interfaces vlan60
    vlan60    
    eth6      now going down itself
    eth6      device: National Semiconductor Corporation DP83815 (MacPhyter) Ethernet Controller
soekris2:~ # ifup eth6
    eth6      device: National Semiconductor Corporation DP83815 (MacPhyter) Ethernet Controller
soekris2:~ # ifup vlan60
    vlan60    
soekris2:~ # cat /proc/net/igmp6 |fgrep eth6
8    eth6            ff0200000000000000000001ff000000     2 00000004 0
8    eth6            ff0200000000000000000001ffca3c42     2 00000004 0
8    eth6            ff020000000000000000000000000001     1 0000000C 0

with the following in /var/log/messages:

Apr 29 08:11:49 soekris2 ifdown:     eth6      is still used from interfaces vlan60
Apr 29 08:11:49 soekris2 ifdown:     vlan60    
Apr 29 08:11:50 soekris2 dhcpd: receive_packet failed on vlan60: Network is down
Apr 29 08:11:51 soekris2 ifdown:     eth6      now going down itself
Apr 29 08:11:51 soekris2 ifdown:     eth6      device: National Semiconductor Corporation DP83815 (MacPhyter) Ethernet Controller
Apr 29 08:11:52 soekris2 kernel: eth6: remaining active for wake-on-lan
Apr 29 08:11:58 soekris2 ifup:     eth6      device: National Semiconductor Corporation DP83815 (MacPhyter) Ethernet Controller
Apr 29 08:11:58 soekris2 kernel: eth6: DSPCFG accepted after 0 usec.
Apr 29 08:11:58 soekris2 kernel: eth6: link up.
Apr 29 08:11:58 soekris2 kernel: eth6: Setting full-duplex based on negotiated link capability.
Apr 29 08:11:59 soekris2 SuSEfirewall2: SuSEfirewall2 not active
Apr 29 08:12:02 soekris2 ifup:     vlan60    
Apr 29 08:12:03 soekris2 SuSEfirewall2: SuSEfirewall2 not active
Apr 29 08:12:25 soekris2 radvd[29668]: resetting ipv6-allrouters membership on vlan60
Apr 29 08:13:55 soekris2 radvd[29668]: resetting ipv6-allrouters membership on vlan60
Apr 29 08:15:51 soekris2 radvd[29668]: resetting ipv6-allrouters membership on eth6
Apr 29 08:17:16 soekris2 radvd[29668]: resetting ipv6-allrouters membership on vlan60
Apr 29 08:17:30 soekris2 radvd[29668]: resetting ipv6-allrouters membership on eth6
Apr 29 08:20:15 soekris2 radvd[29668]: resetting ipv6-allrouters membership on eth6
Apr 29 08:20:25 soekris2 radvd[29668]: resetting ipv6-allrouters membership on vlan60
Apr 29 08:23:21 soekris2 radvd[29668]: resetting ipv6-allrouters membership on vlan60
Apr 29 08:23:21 soekris2 radvd[29668]: resetting ipv6-allrouters membership on eth6

I then restarted radvd-1.6 and the problem went away:

soekris2:~ # cat /proc/net/igmp6 |fgrep eth6
8    eth6            ff020000000000000000000000000002     1 00000004 0
8    eth6            ff0200000000000000000001ff000000     2 00000004 0
8    eth6            ff0200000000000000000001ffca3c42     2 00000004 0
8    eth6            ff020000000000000000000000000001     1 0000000C 0


So the conclusion so far is that with radvd-1.1 and 1.6 when an interface goes down and then up radvd cannot join the group all-routers.

Now, this could be a kernel bug (I'm running 2.6.27) butI don't see any relevant fixes in newer kernels, and trying a new kernel is not that easy for me.

Can somebody try the above scenario (down+up interface while radvd is running) on a newer kernel?


Regards,
  Ivan