taking a vsphere snapshot of Sharpoint SQl servers inf Alwayson configuration.

Yes, this is a tricky situation. Basically VMware and Microsoft both say you shouldn't use snapshots for sql clusters.
https://social.technet.microsoft.com/Forums/sharepoint/en-US/e5abf633-9023-4f24-a707-2680cced28e8/sharepoint-farm-backuprestore-with-vmware-snapshots
http://www.vmware.com/files/pdf/solutions/SharePoint_2010-Availability-and-Recovery-Options.pdf

if you use netapp, they have this: http://community.netapp.com/t5/SnapManager-SnapDrive-and-SnapProtect-Discussions/SMSP-amp-Sharepoint-2013/td-p/21575

If you have DPM: http://technet.microsoft.com/en-us/library/hh757819.aspx

Here is the long way: http://technet.microsoft.com/en-us/library/ff806332%28v=office.15%29.aspx

Hmm. yes, I see.  Thank you.   I am not sure I would want to have to do a restore but backing it up first just in case is not a bad idea.

Perhaps I could shut down the entire farm, snapshot everything and then do my updates/troubleshooting/fixes.

I could then shut it all back down and either remove or revert the snapshots.  That might keep the timing issues at bay.

I would not want to run very long with a growing delta disk.

Do you have any instructions on shutting everything down?  (SQL 2012 in an always on configuration.)

We have not done the snapshot yet but this is probably the way we will go.

I wanted to make sure you got your points .

Thanks, let us know how it goes. The way MS designed Always-On is so that it is ALWAYS on.