Member-specific monitor bug

[m-kratochvil]

Found another discrepancy between Octavia and Big-IP behavior.

When user specifies an alternate monitor IP / port for a member, Octavia treats this as just an attribute of the "main" pool-based monitor, not as a separate entity. But AS3 / Big-IP actually creates standalone, member-specific health monitor object, independent from the pool-based monitor. This member-specific monitor on the Big-IP keeps monitoring the member as long as the alternate monitor IP / port is specified for the member, even if the pool-based monitor is deleted from octavia.

The status of such member is derived from the member status on the Big-IP and it is then either ONLINE or OFFLINE, instead of the expected NO_MONITOR.

This is unexpected behavior from Openstack userbase perspective and we agreed to force remove the alternate monitor IP / port setting if the "main" pool-based monitor is deleted. This will in turn delete the standalone, member-specific monitor object form the Big-IP.

How to reproduce:

1. Create LB with pool and a member
2. Create working pool-based monitor - observe that member status is ONLINE
3. Specify alternate monitor IP or port for the member - observe that member status is ONLINE or OFFLINE (depending on the monitor outcome)
4. Delete the pool-based monitor - observe that the member status remains the same as above, instead of changing to NO_MONITOR
5. Remove the alternate monitor IP / port from the member - observe that the member status changes to NO_MONITOR