Welcome to the Community,
How can I DISCARD the redo log and prevent these snapshots from being recreated?
Usually a snapshot is created either manually or by a backup application. This is not related to the copy operation of the Exchange mailboxes. To find out how to resolve your issue and get rid of the snapshot(s), please attach a screenshot of the datastore browser window, showing all files of this virtual machine (full names, sizes, time/date) and attach the latest vmware.log file as well as the vmsd and vmx file.
Btw. how much free disk space do you currently have on the datastore?
total free space available on the server according to the VI client browser is 80Gb, less than the size of the file being copied. Here's the screenshot of the datastore browser on the guest in question. The VI client shows no manual snapshots, and previous fixes suggested on searching was to create/delete a manual snapshot (no go) and try the 'remove snapshots' function from the service console (also no go - Virtual machine has no snapshots)..
Running out of disk space seems to have caused a serious issue and I think you should immediately open a call with VMware for this!
It looks like the "EDMSERVER02-000002-delta.vmdk" file has been deleted/lost. In addition to the lost file, the last vRanger backup was not successful.
I'm afraid the only option (besides VMware Support) you have is to find out what can be recovered from vRanger.
from the log file:
Jul 17 07:04:16.891: vmx| DISKLIB-VMFS : "/vmfs/volumes/4741974d-7757e7e0-3594-001cc4a80a60/EDMSERVER02/EDMSERVER02-000002-delta.vmdk" : failed to open (25): Backing file doesn't exist. Type 8
Jul 17 07:04:19.088: vmx| DICT annotation = [vRanger Backup: Type [Full], Result [Error], Time [7/16/2011 18:02:24 ]...