+++ /dev/null
-:orphan:
-
-======================================================
- osdmaptool -- ceph osd cluster map manipulation tool
-======================================================
-
-.. program:: osdmaptool
-
-Synopsis
-========
-
-| **osdmaptool** *mapfilename* [--print] [--createsimple *numosd*
- [--pgbits *bitsperosd* ] ] [--clobber]
-
-
-Description
-===========
-
-**osdmaptool** is a utility that lets you create, view, and manipulate
-OSD cluster maps from the Ceph distributed storage system. Notably, it
-lets you extract the embedded CRUSH map or import a new CRUSH map.
-
-
-Options
-=======
-
-.. option:: --print
-
- will simply make the tool print a plaintext dump of the map, after
- any modifications are made.
-
-.. option:: --clobber
-
- will allow osdmaptool to overwrite mapfilename if changes are made.
-
-.. option:: --import-crush mapfile
-
- will load the CRUSH map from mapfile and embed it in the OSD map.
-
-.. option:: --export-crush mapfile
-
- will extract the CRUSH map from the OSD map and write it to
- mapfile.
-
-.. option:: --createsimple numosd [--pgbits bitsperosd]
-
- will create a relatively generic OSD map with the numosd devices.
- If --pgbits is specified, the initial placement group counts will
- be set with bitsperosd bits per OSD. That is, the pg_num map
- attribute will be set to numosd shifted by bitsperosd.
-
-.. option:: --test-map-pgs [--pool poolid]
-
- will print out the mappings from placement groups to OSDs.
-
-.. option:: --test-map-pgs-dump [--pool poolid]
-
- will print out the summary of all placement groups and the mappings
- from them to the mapped OSDs.
-
-
-Example
-=======
-
-To create a simple map with 16 devices::
-
- osdmaptool --createsimple 16 osdmap --clobber
-
-To view the result::
-
- osdmaptool --print osdmap
-
-To view the mappings of placement groups for pool 0::
-
- osdmaptool --test-map-pgs-dump rbd --pool 0
-
- pool 0 pg_num 8
- 0.0 [0,2,1] 0
- 0.1 [2,0,1] 2
- 0.2 [0,1,2] 0
- 0.3 [2,0,1] 2
- 0.4 [0,2,1] 0
- 0.5 [0,2,1] 0
- 0.6 [0,1,2] 0
- 0.7 [1,0,2] 1
- #osd count first primary c wt wt
- osd.0 8 5 5 1 1
- osd.1 8 1 1 1 1
- osd.2 8 2 2 1 1
- in 3
- avg 8 stddev 0 (0x) (expected 2.3094 0.288675x))
- min osd.0 8
- max osd.0 8
- size 0 0
- size 1 0
- size 2 0
- size 3 8
-
-In which,
- #. pool 0 has 8 placement groups. And two tables follow:
- #. A table for placement groups. Each row presents a placement group. With columns of:
-
- * placement group id,
- * acting set, and
- * primary OSD.
- #. A table for all OSDs. Each row presents an OSD. With columns of:
-
- * count of placement groups being mapped to this OSD,
- * count of placement groups where this OSD is the first one in their acting sets,
- * count of placement groups where this OSD is the primary of them,
- * the CRUSH weight of this OSD, and
- * the weight of this OSD.
- #. Looking at the number of placement groups held by 3 OSDs. We have
-
- * avarge, stddev, stddev/average, expected stddev, expected stddev / average
- * min and max
- #. The number of placement groups mapping to n OSDs. In this case, all 8 placement
- groups are mapping to 3 different OSDs.
-
-In a less-balanced cluster, we could have following output for the statistics of
-placement group distribution, whose standard deviation is 1.41421::
-
- #osd count first primary c wt wt
- osd.0 8 5 5 1 1
- osd.1 8 1 1 1 1
- osd.2 8 2 2 1 1
-
- #osd count first primary c wt wt
- osd.0 33 9 9 0.0145874 1
- osd.1 34 14 14 0.0145874 1
- osd.2 31 7 7 0.0145874 1
- osd.3 31 13 13 0.0145874 1
- osd.4 30 14 14 0.0145874 1
- osd.5 33 7 7 0.0145874 1
- in 6
- avg 32 stddev 1.41421 (0.0441942x) (expected 5.16398 0.161374x))
- min osd.4 30
- max osd.1 34
- size 00
- size 10
- size 20
- size 364
-
-
-Availability
-============
-
-**osdmaptool** is part of Ceph, a massively scalable, open-source, distributed storage system. Please
-refer to the Ceph documentation at http://ceph.com/docs for more
-information.
-
-
-See also
-========
-
-:doc:`ceph <ceph>`\(8),
-:doc:`crushtool <crushtool>`\(8),
Code Review / stor4nfv.git / blobdiff