Red Hat Bugzilla – Bug 841967
"ip", "netstat" and "route" commands always show IPv6 cached as well as configured routes
Last modified: 2013-04-19 13:37:59 EDT
Description of problem:
This is a duplicate of https://bugzilla.redhat.com/show_bug.cgi?id=736444
However, I couldn't figure out how to re-open that bug, and it applies to Fedora 15 anyway.
Version-Release number of selected component (if applicable):
kernel is 3.4.0-1.fc17.i686.PAE
Always, apparently on any Fedora 17 or 16 machine (15 as well?)
Steps to Reproduce:
1. Configure IPv6 and generate some IPv6 traffic
2. View the IPv6 routing table with any of the following
ip -6 route
route -n -A inet6
netstat -A inet6 -rn
3. Look at the output - see that it includes IPv6 caches entries
Routing table shows cached as well as configured entries in all tools, so it's impossible to see which entries are configured, and which are cached and will expire / can be ignored.
Cached routes should only be visible if asked for with:
ip -6 route show table cache
...as is the case for IPv4, or older kernels.
This is a behaviour change. I believe it worked as expected in Fedora 14, but can't be sure.
It works as expected in RHEL6 and earlier.
Kernel 3.4.0 is considerably outdated, does this still happen with 3.5.3?
It happens with kernel 3.4.7 under F16. 3.4.7 was tagged 29 Jul 2012, and the RPM built 30 Jul 2012, and the gitweb history for the stable kernel reports no obvious related changes to the net/ipv6 tree since then.
Do you have a specific reason to assume it *doesn't* happen with 3.5.3?
We only have a couple of F17 machines and can't take a reboot to get the new kernel in at the moment. It might be easier to try and reproduce it yourself locally if you have a 3.5.3 machine.
Otherwise, we'll schedule a reboot next week and look then.
ip, route and netstat have shown cached routes for quite some time now. If you just want to see configured routes you need to filter by proto, i.e.:
ip -6 route list proto statc
ip -6 route list proto kernel
ip -6 route list proto <tableid>
*** Bug 736444 has been marked as a duplicate of this bug. ***