writeboosttab(5) mappings of cache(d) devices




The file writeboosttab contains information about mappings between caching and cached block devices for writeboost utility.

Each mapping is described on a separate line; Empty lines and lines starting with '#' are ignored; Fields on each line are separated by tabs or spaces;

The first field (dm_name)

This field describes the name of device-mapepr block device that will be created as result of mapping.

Typically after successful mapping the dm_name will appear in the /dev/mapper folder.

The second field (hdd_device)

This field describes path to the cached block device, typically "slow" (rotational) HDD.

The third field (ssd_device).

This field describes path to the caching block device, typically "fast" SSD.

The forth field (options)

This optional field describes comma-separated list of options passed to dm-writeboost.

It is recommended to use reliable paths to block devices like /dev/disk/by-uuid/{UUID} or similar.


The following is an example of an entry in the /etc/writeboosttab file:

 cached_hdd  /dev/disk/by-uuid/2e8260bc-024c-4252-a695-a73898c974c7  /dev/disk/by-partuuid/43372b68-3407-45fa-9b2f-61afe9c26a68  writeback_threshold=70,sync_data_interval=3600




 Dmitry Smirnov <[email protected]>


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