snapm-plugins.d - Man Page

/etc/snapm/plugins.d/*.conf

Files in /etc/snapm/plugins.d are loaded during the initialisation of snapm and provide configuration options that affect the behaviour of plugins.

The files are structured in INI format: section headers appear in square brackets and configuration values appear as key-value pairs with one pair per line.

Limits

The Limits section may contain the MaxSnapshotsPerOrigin and MaxSnapshotsPerOriginPool keys that place limits on the maximum number of snapshots per origin device and thin pool respectively.

Plugins may opt-in to applying these options depending on the specific snapshot back end. For example, lvm2-cow implements the MaxSnapshotsPerOrigin key since excessive per-origin snapshots using the device-mapper dm-snapshot target leads to read and write IO performance degradation. The lvm2-thin and stratis plugins on th other hand respect the MaxSnapshotsPerPool key since they share the same underlying dm-thin implementation.

The values in both cases are a single non-negative integer specifying the maximum allowed number of snapshots across all snapshot sets and unmanaged snapshots.

Priority

The Priority section may contain the PluginPriority key. Setting this key to an integer value greater than zero will override the default priority value for the corresponding plugin. This can be used, for example, to prefer lvm2-cow snapshots over lvm2-thin even when the latter are available and could be used to snapshot a given source.

Bryn M. Reeves <bmr@redhat.com>

lvm(8), lvcreate(8), lvmthin(7), stratis(8),
Snapm project page: https://github.com/snapshotmanager/snapm
LVM2 resource page: https://www.sourceware.org/lvm2/
Device-mapper resource page: http://sources.redhat.com/dm/

snapm(8).