What are the requirements to establish a Persistent Connection on a server?

Task servers cannot support Persistent Connections on server 2008 and will display "Server does not support persistent connection".

A persistent connection requires an HTTPS connection between the Agents and the desired server. Servers (Notification and Site) are required to have IIS 8.0 and higher, this is due to the need to use web sockets that were introduced in IIS 8. Server 2012 is needed to run IIS 8 as well.

Example:

• Notification server is 2016 with IIS 8 - Communication between agent and server can use Persistent Connections
• Some site servers are 2012 with IIS 8 - Communication between agents and these servers can use Persistent Connections
• Some site servers are at 2008 with IIS7 - Communication to these servers cannot connect over a Persistent Connection (will use legacy communication).

Useful Resources:

• Steps to configure - https://techdocs.broadcom.com/us/en/symantec-security-software/endpoint-security-and-management/it-management-suite/ITMS/Administration/enabling-persistent-connection-in-your-environment-v128534894-d846e70129.html
• IIS 8 WebSocket information - https://docs.microsoft.com/en-us/iis/get-started/whats-new-in-iis-8/iis-80-websocket-protocol-support