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LBackup Frequntly Asked Questions


  • Q : What is LBackup?
  • A : LBackup is a backup wrapper for rsync. LBackup is aimed at system administrators who require reliable backups.
    • LBackup is designed to work with POSIX compliant, *NIX based systems; including Mac OS X, Debian, Ubuntu, BSD and more.


  • Q : Should I be using LBackup?
  • A : Maybe. We recommend that you use a backup tool which meets the requirements of your backup policy.
    • If you have questions relating to LBackup then post a message to the discussion mailing list.
    • If you are looking for an alternative backup tool you may wish to visit the alternatives page.


  • Q : Where can I learn about about LBackup and its' features?
  • A : Visit the about page. Also you are welcome to post questions relating to LBackup to the discussion mailing list.


  • Q : Are there mailing lists for discussing the development or asking questions regarding LBackup?
  • A : Yes. Visit the mailing lists page.



  • Q : How can I see LBackup in action without having to go though the install process?
  • A : Visit the screencats page, and see for yourself how LBackup works.



  • Q : Under which license is LBackup released.
  • A : The LBackup backup program is released under the GNU GPL.


  • Q : How much do I have to pay to use LBackup?
  • A : You pay nothing. But that's not all, act now and take advantage of our amazing buy one get one free offer.



  • Q : Is there professional support available for LBackup?
  • A : Yes, visit the LBackup support page for details.




  • Q : How do I know that LBackup is safe to run on my computer?
  • A : Take our word for it.
  • A : Inspect the source code yourself.
  • A : Assume that because LBackup is used by various prominent institutions that it is safe.
  • A : Use some anti-malware software to scan the LBackup download.


  • Q : Will LBackup preserve the various Mac OS X specific meta data?
  • A : Some versions of rsync preserve various Mac OS X related metadata.
  • A : Setup a backup and confirm that your backups preserve the metadata required by your backup policy.
  • A : Mac OS X specific metadata such as ACL's and resource forks may be preserved provided the following criteria are meet :


  • Q : WARNING : This copy of RSYNC may not support certain Mac OS X meta-data. What does this message mean?
  • A : Some versions of rsync will not preserve certain Mac OS X related metadata.
  • A : Check that your backups contain all the metadata your backup policy requires.
  • A : You are not using rsync v3 compiled according to these instructions.



  • Q : Will LBackup work with Mac OS X Server?
  • A : Yes. LBackup is an open source backup solution for Mac OS X Server.
  • A : LBackup is able to transfer user files from Mac OS X server.
  • A : This data may be regularly copied automatically over the network via SSH.


  • Q : LBackup hangs towards the end of a backup on Mac OS 10.6 (Snow Leopard)?
  • A : If you are using a custom version of rsync then it is recommended that you compile a new version for your system.
  • A : This issue is outlined on the upgrade notes page.


  • Q : What is the following error : “LSOpenURLsWithRole() failed”?
  • A : On Mac OS X this part of system security.
  • A : A pre or post action script may be trying to interact with the GUI, and is not being granted access.


  • Q: What is the following warning : “some files vanished before they could be transferred (code 24) at main.c(1042)”?
  • A : If a file which is scanned for transfer is removed from the file system is removed then rsync will output this error.


  • Q: What is the following warning : “rsync: rsync_xal_set: lsetxattr(<snip>) failed: Invalid argument (22)”?
  • A : This kind of error is a problem with transferring an extended attribute.
    • It is possible to use the xattr command to edit / modify the extended attributes of any problimatic files. If you require assistance then please contact us.



  • Q : How do I install LBackup on Debian / Ubuntu / Mac OS X?
  • A : Follow the instructions on the install page



  • Q : Will LBackup support the backup of multiple source directories / files with a single configuration directory?
  • A : No. At this point you are limited to one backup directory source per backup configuration.
    • It is possible to backup the root directory of a system and then add entries into the excludes file.
    • It is possible to configure multiple backup configuration directories; one for each source directory / file.



  • Q : What is the recommended destination file system type when running on Darwin (Mac OS X)?
  • A : HFS+ is the typically the recommended choice. Many other file systems will also work.
    • Some file systems will not support hard linking, files greater than 4GB or special file types such as symbolic links. If you are having success using a destination file system other than HFS+ on Mac OS X then please share your experiences.


  • Q : I would like to backup data in the cloud, is LBackup an option?
  • A : Yes (for some services). LBackup requires no graphical interface for setup, maintenance, backup or restore.
    • LBackup is fully configurable via a console. Backup to and from servers within a cloud evniroment on which you have a shell account and which also meet the other LBackup requirements is not only possible but is also reliable. Further details regarding cloud computing are available from this Wikipedia article.


  • Q : Backup server running Mac OS X is slow or unresponsive even when no backup is taking place.
  • A : As a first step visit the spotlight wiki page and check to see if spotlight is enabled on your backup volume.
  • A : Next it may be that build_hd_index is working to catalog all the files within your backup.
  • A : Use a system monitoring tool (OS X - /Applications/Activity Monitor.app) to further investigate.


  • Q : Seeing the following error : “rsync: unpack_smb_acl: sys_acl_get_info(): Undefined error: 0 (0)”
  • A : Try making initiating a full backup. It may be that the ACL's are not matching between systems.
    • This may happen after a major system upgrade or migration. The users for the ACL's may not not be correct. Hence this error is being issued.
  • A : If ACL's do not need to be preserved, then pointing then disabling ACL preservation is an option.
    • First, start with an empty backupDest directory ((first run full backup)
    • Next, add the following line to your LBackup configuration :
  disable_acl_preservation="YES"
  • A : Another approach is to use the use is to enable numeric ID mapping.
    • Note : some versions of rsync have a bug which result in this approach failing, if this is the case for you either switch to a different version of rsync or try either of the approaches listed above.
    • First, start with an empty backupDest directory ((first run full backup)
    • Next, add the following lines to your LBackup configuration :
  disable_acl_preservation="NO"
  numeric_ids_enabled="YES"