Hello.
Today I will talk about citrix maintenance mode for application servers and how it help us  for DR fail overs.
Few words about maintenance mode by citrix.  It was introduced by citrix To temporarily stop connections by users to perform any administrative tasks such as applying patches and  upgrades.

So in Disaster Recovery case it’s guarantees that user application will not run on server with wrong behaviour if we disabled this server in portal.

And now i will show how it works on portal. For check i will go to farm server directly with opened citrix console.

also we add diagnostics for mismatch between states of application server in portal and citrix console.