Hi,
If this question is related to ACE then you can achieve as follows:
ace/AJAY(config)# serverfarm host TEST-FARM
ace/AJAY(config-sfarm-host)# rserver VM1
ace/AJAY(config-sfarm-host-rs)# backup-rserver VM2
ace/AJAY(config-sfarm-host-rs)# inservice
The config will look like this :
serverfarm host 1313-GIN-GWAP-SDC-80
rserver VM1
inservice
rserver VM2
inservice standby
So in case if rserver VM1 will fail VM2 server will fulfill the request
Hope that helps.
regards,
Ajay Kumar