It's important to clarify exactly how node-draining is handled internally.
Stingray maintains session persistence records, either internally or in client-side cookies.
Stingray does not time-out session persistence records:
You need to judge when it is safe to take a node out-of-service, based on your understanding of how long a session should remain idle before it is unneeded. You can refer to the connection draining report for this information. When you want to take a node out of service, use the 'Disabled' setting; this prevents Stingray from making any new connections to the node, but allows exisiting connections to complete.
For more details on session persistence, please refer to the document Session Persistence - implementation and timeouts
in my case I must have persistence classes, as I continually and getting new connections.. Its been 20-30 minutes now. So should I simple disable a node instead where I understand, all connections will be dropped, so I can perform maintenance on the node?
I've updated the reply above as it was incomplete and out-of-date.
Yes - if you are confident that existing sessions have completed, then you can mark the node as 'disabled' and then take it out of service.
In the case where you are using non-unique session persistence keys (for example, the IP address), then a session persistence record can be reused and this means that new sessions may be routed to a draining node. If possible, use a cookie-based session persistence method as this uniquely identifies a client session.