There is a small problem when I use a dedicated volume for the backup:
SEVERE: Cannot perform a backup. Please be sure jenkins/hudson has write privileges in the configured backup path '/var/backup/jenkins'.
java.io.IOException: Failed to list contents of /var/lib/jenkins/lost+found
at org.apache.commons.io.FileUtils.doCopyDirectory(FileUtils.java:1408)
at org.apache.commons.io.FileUtils.doCopyDirectory(FileUtils.java:1426)
at org.apache.commons.io.FileUtils.copyDirectory(FileUtils.java:1389)
at org.apache.commons.io.FileUtils.copyDirectory(FileUtils.java:1310)
at org.jvnet.hudson.plugins.thinbackup.backup.HudsonBackup.backupAdditionalFiles(HudsonBackup.java:289)
at org.jvnet.hudson.plugins.thinbackup.backup.HudsonBackup.backup(HudsonBackup.java:171)
at org.jvnet.hudson.plugins.thinbackup.ThinBackupPeriodicWork.backupNow(ThinBackupPeriodicWork.java:89)
at org.jvnet.hudson.plugins.thinbackup.ThinBackupPeriodicWork.execute(ThinBackupPeriodicWork.java:70)
at org.jvnet.hudson.plugins.thinbackup.hudson.model.AsyncPeriodicWork$1.run(AsyncPeriodicWork.java:53)
at java.lang.Thread.run(Thread.java:748)
The workaround is quite clear. On the other hand: 'lost+found' is a well known name, thinBackup should ignore it if it is unreadable.
+1
I've added a document in the wiki to avoid having dozens of plugins doing the same thing: https://wiki.jenkins-ci.org/display/JENKINS/Before+starting+a+new+plugin