[Bug 271168] [carp] Packets send to carp gateway are forwarded to all ECMP routes

From: <bugzilla-noreply_at_freebsd.org>
Date: Mon, 01 May 2023 14:05:51 UTC
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=271168

--- Comment #1 from Arnaud HOUDELETTE <arnaud.houdelette@normandie-univ.fr> ---
Considering this scenario : 

              +--------------------------+
              |                          |
+--------+    |        FreeBSD           |
| Host 1 +----+ifAdm   router box        |
+--------+    |carp                      |
              |                          |
              |   vl10             vl11  |
              +-----+---------------+----+
                    |               |
                 +--+---+        +--+---+
                 | RT-A |        | RT-B |
                 +--+---+        +---+--+
                    |                |
                  --+---------+------+----
                              |
                          +---+----+
                          | Host 2 |
                          +--------+


Carp ifAdm IP is default gateway for Host 1
The router box as two routes to Host 2 network (ECMP), via RT-A and RT-B

Packets send by Host 1 to Host 2 are received twice (via RT-A and RT-B).

carp if is configured as follow : 

ifconfig_ifAdm="169.254.1.1/24"
ifconfig_ifAdm_alias0="inet vhid 1 pass testpass alias 195.220.135.193/26"

removing carp on interface does not show the issue :
ifconfig_ifAdm_alias0="inet alias 195.220.135.193/26"

-- 
You are receiving this mail because:
You are the assignee for the bug.