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I'm setting up an Ubuntu box to backup one of our servers using BackupPC. I've got 2x 2tb hard drives and I've set up Greyhole to duplicate the data from the samba share /mnt/samba/backups across both drives incase of failure.

I need to set BackupPC to use /mnt/samba/backups as its topdir location, ensuring that all data is backed up across the greyhole pool.

I don't really know much about symlinks or mounting so I tried each set of commands in Sourceforge's BackupPC wiki article, checked if it worked, then moved onto the next set of commands. I've also tried changing the topdir location in BackupPC's file.

I think I've tried every combination of changing/not changing the topdir location and each of the methods in the wiki article.

Every time I've tried to start BackupPC after any of these changes I receive the following error message:

Can't create a test hardlink between a file in /mnt/samba/backups/pc and /mnt/samba/backups/cpool.  Either these are different file systems, or this file system doesn't support hardlinks, or these directories don't exist, or there is a permissions problem, or the file system is out of inodes or full.  Use df, df -i, and ls -ld to check each of these possibilities. Quitting...

I'm basically really stuck now. I've chosen to use Greyhole instead of RAID1 over LVM and there isn't enough space left on the main partition to store a full backup. This is the last step I need to configure to complete my setup.


After trying many potential solutions and going over and over the same steps many times I found a forum post stating that you cannot use a Samba share for the BackupPC pool, because Samba shares don't support the hardlinks that BackupPC uses for its pooling feature.

So basically if anyone else is stuck on the same issue, don't use BackupPC with Greyhole as Greyhole requires you to locally mount using a Samba share it can't work with BackupPC.

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