mirror of https://github.com/trapexit/mergerfs.git
1.4 KiB
1.4 KiB
HOW IT WORKS
mergerfs logically merges multiple paths together. Think a union of sets. The file/s or directory/s acted on or presented through mergerfs are based on the policy chosen for that particular action. Read more about policies below.
A + B = C
/disk1 /disk2 /merged
| | |
+-- /dir1 +-- /dir1 +-- /dir1
| | | | | |
| +-- file1 | +-- file2 | +-- file1
| | +-- file3 | +-- file2
+-- /dir2 | | +-- file3
| | +-- /dir3 |
| +-- file4 | +-- /dir2
| +-- file5 | |
+-- file6 | +-- file4
|
+-- /dir3
| |
| +-- file5
|
+-- file6
mergerfs does not support the copy-on-write (CoW) or whiteout behaviors found in aufs and overlayfs. You can not mount a read-only filesystem and write to it. However, mergerfs will ignore read-only filesystems when creating new files so you can mix read-write and read-only filesystems. It also does not split data across filesystems. It is not RAID0 / striping. It is simply a union of other filesystems.