Bug #9136

IPv6 Tracking Interfaces Lose IPv6 Address in Certain Cases

Added by Chris Linstruth almost 2 years ago. Updated over 1 year ago.

Target version:
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IPv6 assigned to inside interfaces seem to lose their assignments one by one over time upon renewal or interface reset. This seems to only occur if the time necessary to complete the renewal is more than X. It takes a couple of minutes for all of the interfaces to lose their assignments. Seems to be about one every 10 seconds. It also only appears to impact VLAN interfaces, not direct interfaces (vmnet0, igb1).

To test this I installed a new 2.4.4.CE VM and created WAN (vtnet1) LAN (vtnet0) and 10 VLANs on vtnet1 (vtnet1.3501 - vtnet1.3510, OPT1-OPT10).

LAN and OPT1-OPT10 were all configured as Static IPv4, Track Interface, WAN IPv6.

WAN was configured for DHCP, DHCP6, with a /56 Prefix Delegation.

Upon boot, all inside interfaces receive track interface assignments and everything works.

But if you Edit/Save WAN, All interfaces receive track interface assignments but then some inside interfaces drop their address assignments.

As far as I can tell, this occurs when this is logged:

Nov 18 23:34:01 check_reload_status updating dyndns opt9
Nov 18 23:34:01 kernel vlan9: changing name to 'vtnet0.3510'

I am rebooting again to try to watch if it reoccurs on a DHCP6 renewal. That will take some time.


#1 Updated by Jim Pingle almost 2 years ago

The log messages look the same as #9115, might possibly be the same root cause.

#2 Updated by Dean Attewell almost 2 years ago

I also see this, IPv6 static leases disappearing

#3 Updated by Luiz Souza almost 2 years ago

  • Target version set to 48

#4 Updated by Luiz Souza almost 2 years ago

  • Assignee set to Luiz Souza

#5 Updated by Chris Linstruth almost 2 years ago

The fix for #9115 has made this much better but I still see these issues:

Editing/Saving the VLAN parent interface will cause the same issue as originally described. All interfaces receive the tracked prefix assignment then as the VLAN interfaces are reconfigured they lose the assigned prefix one-by-one.

Editing/Saving any VLAN interface causes all VLANs and the parent interface to temporarily lose their IPv6 tracked prefix. After a time they are all reapplied and appear to be permanent.

#6 Updated by Jim Pingle over 1 year ago

  • Target version changed from 48 to 2.5.0

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