Mirroring is a nice thing when we think of migrating/moving big repositories considering the administrative tasks and the side effects involved.
Right now, the SCM-Manager provides the facility to mirror any type of repository. But if it fails in between for whatever the reason is, it would not start/continue syncing because SVNSYNC has to be called with
--allow-non-empty switch. I am not sure about the equivalent switch in SVNKit but this is a missing piece.
With big repositories, if the sync stops in between, then removing it and restarting it from the scratch is not a workable approach.
So please enable/facilitate
--allow-non-empty option in SVN mirror page and make sure to set this property to the SVNPROPS of the target SVNREPO before calling the
SVNSYN SYNC file:///repositories/mysvnrepo function.