When flush-connections is enabled in load-balancing, then when interface state is changing daemon wan_lb execute:
conntrack -F conntrack -F expect
But, when conntrackd is running, the first command can't finish up and hangs. As I see, conntrack sending the command to a kernel, but don't receive any answers: Also, this leads to a continuous CPU usage by conntrack and conntrackd.
root 7792 81.7 1.0 24416 5332 ? S<s 17:00 0:33 /usr/sbin/conntrackd -C /etc/conntrackd/conntrackd.conf root 7829 7.0 0.1 12652 888 pts/1 R+ 17:00 0:02 conntrack -F
This problem breaks load-balancing functional.
Instead of flushing table, we can delete its content. This works without problems. I propose to change command to the followed to avoid problems:
Otherwise, we need to block the ability to enable both options at the same time.