Comment 5 for bug 1833730

Test pre-condition:
make nova-api-proxy running on the standby controller,
make sure "openstack server list" cmd execution properly;
reboot the standby controller.

AFter standby controller reboot, run "openstack server list" cmd every min on multi terminals
Test result:
0' executing cmd, cmd return: Internal Server Error (HTTP 500)
1' executing cmd, cmd hung
2' still hung
3' still hung
3.5' return as Connection timed out

Same scenario happened on different session. cmd hung for 2.5' mins then return time out.

After 6-7 mins standby controller boot up, but cmd still hung up.

Around 12 mins after reboot. cmd execution is back to normal.