Neutron traceback when an external network without IPv6 subnet is attached to an HA Router
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
neutron |
Fix Released
|
High
|
Sridhar Gaddam | ||
Kilo |
Fix Released
|
Undecided
|
Unassigned |
Bug Description
For an HA Router which does not have any subnets in the external network, Neutron
sets the IPv6 proc entry[1] on the gateway interface to receive Router Advts from
external IPv6 router and configure a default route pointing to the LLA of the external IPv6 Router.
Normally for an HA Router in the backup state, Neutron removes Link Local Address (LLA)
from the gateway interface.
In Kernel version 3.10 when the last IPv6 address is removed from the interface,
IPv6 is shutdown on the iface and the proc entries corresponding to the iface are deleted (i.e., /proc/sys/
This issue is resolved in the later kernels [2], but the issue exists on platforms with Kernel version 3.10
When IPv6 proc entries are missing and Neutron tries to configure the proc entry we see the following traceback [3] in Neutron.
[1] /proc/sys/
[2] http://
[3] Trace:
Command: ['ip', 'netns', 'exec', 'qrouter-
Exit code: 255
Stdin:
Stdout:
Stderr: sysctl: cannot stat /proc/sys/
Changed in neutron: | |
assignee: | nobody → Sridhar Gaddam (sridhargaddam) |
status: | New → In Progress |
Changed in neutron: | |
status: | Fix Committed → Fix Released |
Changed in neutron: | |
milestone: | liberty-rc1 → 7.0.0 |
kernel 3.10 is used in RHEL 7.1, so it means HA routers are not working for IPv6 external networks with no subnets for the platform.