Linux LVM快照脏块位图

Question

I'm looking for ways to create full/incremental snapshot backups on Linux for different file systems.

I wanted pointers on which LVM/Device mapper source files to look for regarding creating snapshots (COW mechanism) and where changed block bit maps are stored for incremental backups.

Is there API calls available on Device mapper to create a snapshot and get the dirty block bit map during incremental?

Also, is there any other mechanism available on Linux to create snapshots which is common across LVM volumes and raw disk file systems?

Answer 1

It's only a quick and partial answer, but since kernel 3.6, you can access the snapshot metadata and perform an incremental backup if you use the dm-thin target.

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