With IPHost Network Monitor you can run simple snmp requests against a F5 Network device in your network.
lbRouterVServCurNodesUp
lb Router V Serv Cur Nodes Up
1.3.6.1.4.1.3375.1.2.1.1.3.4.1.12
The current number of nodes associated with the virtual server that are up.
Back to F5-3DNS-MIB MIB page.
IPHost Network monitor allows you to monitor lbRouterVServCurNodesUp on F5 Network device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring F5 Network switches right now.