Sync between the Content DB and Profile DB is not happening since a week, even the command "
stsadm -o sync -DeleteOldDatabases 0" is failed to respond. is there any other specific command can be used here?
'A failure occurred during the processing of this command. Check diagnostic logs for more information' is in fact "Access Denied error to the User Profile Service Application".
TO resolve this issue, Navigate to Manage Service Applications ---> User Profile Service Application Name ----> select Permissions from the ribbon ----> Add your user account with full control right.
stsadm.exe -o sync -deleteolddatabases command. Hope this helps
What method are you using to verify whether the sync is working or not? Are you looking at the timer jobs and see that they aren't running? Are you just looking at one person and seeing their data isn't correct? Etc.
In the past I've seen this happen when someone is just looking at someone's data and typically this is after the person's userid (samaccountname) has changed. Then we usually run migrateuser to clear it up.
Sometimes I've seen it when a database or site collection is readonly, or over it's quota, that can affect the sync and the migrateuser command.