Problem with link aggregation + sshd

Giulio Ferro auryn at
Tue Aug 21 21:26:02 UTC 2012

Scenario : freebsd 9 stable (yesterday) amd64 on HP server with 4 nic (igb)

1 nic is connected standalone to the management switch, the 3 other nics
are connected to a switch configured for aggregation.

If I configure the first nic (igb0) there is no problem, I can operate
as I normally do and sshd functions normally.

The problems start when I configure the 3 other nics for aggregation:

in /etc/rc.conf

ifconfig_lagg0="laggproto lacp laggport igb1 laggport igb2 laggport igb3"

I restart the server and the aggregation seems to work correctly, in
fact ifconfig returns the correct lagg0 interface with the aggregated
links, the correct protocol (lacp) and the correct ip address and the
status is active. I can ping other IPs on the aggregated link.

Also the other (standalone) link seems to work correctly. I can ping
that address from other machines, and I can ping other IPs from that

DNS lookups work ok too I can also use telnet to connect to pop3
servers so there seems to be no problem on the network stack.

But if I try to connect to the sshd service on that server, it hangs
indefinitely. On the server I find two sshd processes:
/usr/sbin/sshd -R

There is no message in the logs.

If I try to kill sshd (/etc/rc.d/sshd stop) I can't. it just stays there
forever waiting for the pid to die (it never does)

Even ssh client doesn't seem to work. In fact, if I try to connect to
another server, the ssh client may start to work correctly, then soon
or later it just hangs there forever, and I can't kill it with ctrl-c.

No firewall is configured, there is nothing else working on this server.

Thanks for any suggestions...

More information about the freebsd-stable mailing list