New in vSphere 5.1 is a completely redesigned vCenter Web Client. Many of us would have never used the Web Client in previous versions of vSphere and for the few that did would have been quickly turned off by it.
VMware have put a lot of effort in this new version, to the point where many of the new features in 5.1 are only available in the Web Client. Moving forward the C# client will no longer be developed and 5.1 will be the last version.
One of the features of the C# client was the ability to stay logged in indefinitely. For good or for bad (from a security view) I like it. My workstation is always secured when away from it and I liked being able to come back and have the vCenter Client connected and running.
With the new 5.1 Web Client a session is ended after 2 hours of being idle. In all honesty this isn’t too impractical and will suit most people. That being said I like being able to log in at the start of the day and know that I will still be logged in at the of my day even if I having been active on the new web client.
Currently there is no setting within the Web Client that will allow you to change the idle login timeout. The timeout can be changed through a config file, both in Windows and the vCenter Virtual Appliance.
Windows
Navigate to %SYSTEMDRIVE%UsersAll UsersVMwarevSphere Web Clientwebclient.properties
Uncomment the line (remove #) and change the value in minutes for session.timeout = 120
Restart the VMware vSphere Web Client service
Virtual Appliance
Navigate to /var/lib/vmware/vsphere-client/webclient.properties
Uncomment the line and change the value in minutes for session.timeout = 120
Restart the Web Client using /etc/init.d/vsphere-client restart