So recently I had to move a datastore location to a new disk since where we had it was running low on physical space. To do this is very straight forward and covered in a previous article, however this one was stubborn.
With the database offline I had copied the data to a new disk and verified it matched. But it stayed on this step for a number of minutes I never recall it taking so long before.
Problem: When I move an exchange datastore I freezes on validating the destination file paths. Unable to move exchange datastore. Moving exchange datastore takes excessive amount of time.
Looking around online it should only take a number of seconds to check. There was little disk IO just lots of CPU usage since it stalled. I moved another Storage Group to ensure I was not insane and it went right away.
Solution: Remove log files from source and destination if you copied the whole folder.
/!\ Always copy log files never ever delete them until you are sure you need them. Always work with the DB offline and test mounting the DB after making a change.
Comparing the folders I noticed there were a large number of these log files sitting around in the same folder as the DB.
Since the DB was offline I moved them to a different disk to ensure it did not need them. I I remounted the DB and it came up fine without them. I assume they were made during some bad migrations we were working on at the time they were still around.
After removing the files I began the migration again but it still took time validating. I then remembered I had copied the whole folder so the logs were in the source and the destination. Moving them out as well and starting the process over yielded a fast migration!
I assume I could have waited for the system to compare the files and so on but after waiting 30 min for something that normally takes seconds did not sit well with me on a weekend.