search

ocochard / BSDRP

BSD Router Project
https://bsdrp.net
Other
175 stars 38 forks source link

Duplicates packets with Carp and ECMP #39

Closed thetzim closed 1 year ago

thetzim commented 1 year ago

packets entering the router on a carp interface towards a destination having multiple routes in table (bird with netlink flavor) gets routed to all nexthops. Destination receives duplicates packets (one for each router).

The carp interface is the gateway for hosts on a vlan.

thetzim commented 1 year ago

I just opened PR 21168 on the matter.

ocochard commented 1 year ago

I think the correct PR was this one Now, some advice to "fish" an FreeBSD developer (should be the same for all OpenSource project):

  1. You should provide the simplest shell script to reproduce your error (very easy using vnet jail).
  2. Once you done step 1, convert your script as a regression tests and submit it as to improve FreeBSD. Example of multipath regression tests.

With this, you should be able to fish a big developer :-)

thetzim commented 1 year ago

Thanks for the advices. I, indeed, filled the PR too fast, as the problem was elsewhere. After more investigation on the issue, it appears that the culprit was the second carp router which deconfigured carp interface continued to process packets to the carp MAC address.

Configuration / deconfiguration of interfaces seems to be bogus somewhere else.