Virtual server is enabled but is unavailable
Although the virtual server is enabled, is unavailable. This is because a pool member has reached its connection limit.
In this scenario two virtual servers were marked down by health monitor, and the only available virtual server has reached its connection limit.
Virtual server is enabled and ready to receive traffic
This is the business as usual status of a virtual server.
Virtual server is enabled but offline
The virtual server is enabled but is marked offline, the virtual server will not receive any incoming traffic. This indicate pool members might be down which caused the virtual server to be offline.
In this scenario, the http services were down for all pool members.
In this scenario the pool members are all been forced offline; which caused the virtual server to be offline as well.
Interestingly if all pool members are disabled the pool will still indicate as enabled, hence caused virtual server to indicate as enabled as well.
If there is already a persistence to a server traffic will still be sent to the pool member even if it has been disabled.
Virtual server is available but disabled
This happens when you disabled the virtual server, when virtual server is disabled no incoming traffic will be received.
Virtual server status is unknown
Bigip cannot determine the status of the virtual server because there is no health monitor configured for a node or a pool member.