Load Balancers usually send some requests to servers in their "balanced pools". Lack of response tells the Load Balancer to remove the server from the pool, and to distribute incoming requests to remaining servers in that pool.
With SIP Farming switched on, the Load Balancer own requests can be relayed to other servers in the SIP Farm, and responses will come from those servers. This may cause the Load Balancer to decide that the server it has sent the request to is down, and to exclude the server from the pool. To avoid this problem, use the following SIP requests for Load Balancer "pinging":
OPTION sip:aaa.bbb.ccc.ddd:5060 SIP/2.0 Route: <sip:aaa.bbb.ccc.ddd:5060;lr> other SIP packet fields
where aaa.bbb.ccc.ddd is the IP address of the CommuniGate Pro Server being tested.
These packets are processed with the aaa.bbb.ccc.ddd Server, which generates responses and sends them back to the Load Balancer (or other testing device).