Currently a backup server (CentOS 6.8) is showing messages when rsnapshot is running, indicating that there's no space left on the device (/raid; an xfs file system) to write.Below is the output of df -h and df -i which suggest there's plenty of space and inodes available. I initially thought it was maybe some symlinks being copied over that were throwing something off but I'm not sure if that's the case now. ANY help or suggestions would be greatly appreciated.$ df -hFilesystem Size Used Avail Use% Mounted on/dev/sda2  193G 4.8G 178G    3% /tmpfs       16G    0  16G    0% /dev/shm/dev/sda1  190M  54M 127M   30% /boot/dev/sda4   33T  27T 5.6T   83% /raid$ df -iFilesystem    Inodes     IUsed      IFree IUse% Mounted on/dev/sda2   12804096     30531   12773565    1% /tmpfs        4107986         1    4107985    1% /dev/shm/dev/sda1      51200        44      51156    1% /boot/dev/sda4 6984405376 240113152 6744292224    4% /raid
Server Claims No Space Left But Has 5TB Available
centos;hard disk;xfs
Unfortunately, I don't have enough rep to comment yet, so bear with me.Some ideas as to what it may be:Is the first terabyte of disk space on the raid used up? (from http://xfs.org/index.php/XFS_FAQ)By default, with 32bit inodes, XFS places inodes only in the first 1TB of a disk. If you have a disk with 100TB, all inodes will be stuck in the first TB. This can lead to strange things like disk full when you still have plenty space free, but there's no more place in the first TB to create a new inode. Also, performance sucks.  To come around this, use the inode64 mount options for filesystems >1TB. Inodes will then be placed in the location where their data is, minimizing disk seeks.  Beware that some old programs might have problems reading 64bit inodes, especially over NFS.If so, try using the inode64 option.User/Group/Project quota can be used to limit the amount of space a user/group/directory can take up:https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Storage_Administration_Guide/xfsquota.htmlTry disabling them if they're enabled?A user on serverfault seemed to have trouble with the size of some (sparse) files on xfs after upgrading to CentOS version 6.2+:https://serverfault.com/questions/406069/why-are-my-xfs-filesystems-suddenly-consuming-more-space-and-full-of-sparse-fileHope this helps.