Using rsnapshot with the +rsync_long_args=--rsync-path="sudo rsync" command fails with a rsync not found error. If I do a rsync only without using rsnapshot the command works find so it's not related to rsync. In addition if I install rsnapshot on a 12.04 server this issue does not occur even when pulling form the same server.
I believe this is a bug introduced into 14.04 with rsnapshot as I've removed the package from the 14.04 server and cloned the rsnapshot github repo and installed rsnapshot with it and the issue is no longer.
Not sure if it relates to the downstream Debian package/bug of this: Debian Bug report logs - #743310
Has anyone else had this issue and can they confirm the issue? If so I will submit a bug report, but just wanted to be sure before doing so.