Merge pull request #1329 from clebertsuconic/2.3.x

2.3.9 / back to snapshot release
https://bugzilla.redhat.com/show_bug.cgi?id=1013536 - retry creating server lock file on io failure
Merge pull request #1331 from andytaylor/2.3.x

retry creating server lock file on io failure
fix test race condition on backup start by adding flag
Merge pull request #1335 from andytaylor/2.3.x

fix test race condition on backup start by adding flag
https://bugzilla.redhat.com/show_bug.cgi?id=960682 - adding log in case of blocking