Drain stopping allows user sessions to be gracefully removed from disabled servers. This allows users to finish their session before removing servers for maintenance.
Drain stopping only occurs for Layer 7 virtual services with persistence. Once a server is disabled, LoadMaster will automatically drain connections. This means that new sessions will not be sent to that server. However, sessions which have a persistence entry will continue to be directed to that server. This will happen until the persistence entry expires or until the L7 Connection Drain Time expires. This is found in System Configuration > Miscellaneous Options > L7 Configuration.
If the service is Layer 4 only or if the service is L7 without any persistence, drain stopping will not occur. Under these circumstances, no new connections will be sent to a disabled server whatsoever.
- Note: Drain stopping does not affect established sessions. If a client is already connected to a server, that connection will continue until it finishes or is closed due to the idle connection timeout.