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+:orphan:
+
+.. _osdmaptool:
+
+======================================================
+ osdmaptool -- ceph osd cluster map manipulation tool
+======================================================
+
+.. program:: osdmaptool
+
+Synopsis
+========
+
+| **osdmaptool** *mapfilename* [--print] [--createsimple *numosd*
+ [--pgbits *bitsperosd* ] ] [--clobber]
+| **osdmaptool** *mapfilename* [--import-crush *crushmap*]
+| **osdmaptool** *mapfilename* [--export-crush *crushmap*]
+| **osdmaptool** *mapfilename* [--upmap *file*] [--upmap-max *max-optimizations*]
+ [--upmap-deviation *max-deviation*] [--upmap-pool *poolname*]
+ [--save] [--upmap-active]
+| **osdmaptool** *mapfilename* [--upmap-cleanup] [--upmap *file*]
+
+
+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.
+It can also simulate the upmap balancer mode so you can get a sense of
+what is needed to balance your PGs.
+
+
+Options
+=======
+
+.. option:: --print
+
+ will simply make the tool print a plaintext dump of the map, after
+ any modifications are made.
+
+.. option:: --dump <format>
+
+ displays the map in plain text when <format> is 'plain', 'json' if specified
+ format is not supported. This is an alternative to the print option.
+
+.. 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 [--pg-bits bitsperosd] [--pgp-bits bits]
+
+ will create a relatively generic OSD map with the numosd devices.
+ If --pg-bits 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.
+ If --pgp-bits is specified, then the pgp_num map attribute will
+ be set to numosd shifted by bits.
+
+.. option:: --create-from-conf
+
+ creates an osd map with default configurations.
+
+.. option:: --test-map-pgs [--pool poolid] [--range-first <first> --range-last <last>]
+
+ will print out the mappings from placement groups to OSDs.
+ If range is specified, then it iterates from first to last in the directory
+ specified by argument to osdmaptool.
+ Eg: **osdmaptool --test-map-pgs --range-first 0 --range-last 2 osdmap_dir**.
+ This will iterate through the files named 0,1,2 in osdmap_dir.
+
+.. option:: --test-map-pgs-dump [--pool poolid] [--range-first <first> --range-last <last>]
+
+ will print out the summary of all placement groups and the mappings from them to the mapped OSDs.
+ If range is specified, then it iterates from first to last in the directory
+ specified by argument to osdmaptool.
+ Eg: **osdmaptool --test-map-pgs-dump --range-first 0 --range-last 2 osdmap_dir**.
+ This will iterate through the files named 0,1,2 in osdmap_dir.
+
+.. option:: --test-map-pgs-dump-all [--pool poolid] [--range-first <first> --range-last <last>]
+
+ will print out the summary of all placement groups and the mappings
+ from them to all the OSDs.
+ If range is specified, then it iterates from first to last in the directory
+ specified by argument to osdmaptool.
+ Eg: **osdmaptool --test-map-pgs-dump-all --range-first 0 --range-last 2 osdmap_dir**.
+ This will iterate through the files named 0,1,2 in osdmap_dir.
+
+.. option:: --test-random
+
+ does a random mapping of placement groups to the OSDs.
+
+.. option:: --test-map-pg <pgid>
+
+ map a particular placement group(specified by pgid) to the OSDs.
+
+.. option:: --test-map-object <objectname> [--pool <poolid>]
+
+ map a particular placement group(specified by objectname) to the OSDs.
+
+.. option:: --test-crush [--range-first <first> --range-last <last>]
+
+ map placement groups to acting OSDs.
+ If range is specified, then it iterates from first to last in the directory
+ specified by argument to osdmaptool.
+ Eg: **osdmaptool --test-crush --range-first 0 --range-last 2 osdmap_dir**.
+ This will iterate through the files named 0,1,2 in osdmap_dir.
+
+.. option:: --mark-up-in
+
+ mark osds up and in (but do not persist).
+
+.. option:: --mark-out
+
+ mark an osd as out (but do not persist)
+
+.. option:: --mark-up <osdid>
+
+ mark an osd as up (but do not persist)
+
+.. option:: --mark-in <osdid>
+
+ mark an osd as in (but do not persist)
+
+.. option:: --tree
+
+ Displays a hierarchical tree of the map.
+
+.. option:: --clear-temp
+
+ clears pg_temp and primary_temp variables.
+
+.. option:: --clean-temps
+
+ clean pg_temps.
+
+.. option:: --health
+
+ dump health checks
+
+.. option:: --with-default-pool
+
+ include default pool when creating map
+
+.. option:: --upmap-cleanup <file>
+
+ clean up pg_upmap[_items] entries, writing commands to <file> [default: - for stdout]
+
+.. option:: --upmap <file>
+
+ calculate pg upmap entries to balance pg layout writing commands to <file> [default: - for stdout]
+
+.. option:: --upmap-max <max-optimizations>
+
+ set max upmap entries to calculate [default: 10]
+
+.. option:: --upmap-deviation <max-deviation>
+
+ max deviation from target [default: 5]
+
+.. option:: --upmap-pool <poolname>
+
+ restrict upmap balancing to 1 pool or the option can be repeated for multiple pools
+
+.. option:: --upmap-active
+
+ Act like an active balancer, keep applying changes until balanced
+
+.. option:: --adjust-crush-weight <osdid:weight>[,<osdid:weight>,<...>]
+
+ Change CRUSH weight of <osdid>
+
+.. option:: --save
+
+ write modified osdmap with upmap or crush-adjust changes
+
+.. option:: --read <file>
+
+ calculate pg upmap entries to balance pg primaries
+
+.. option:: --read-pool <poolname>
+
+ specify which pool the read balancer should adjust
+
+.. option:: --vstart
+
+ prefix upmap and read output with './bin/'
+
+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 1::
+
+ osdmaptool osdmap --test-map-pgs-dump --pool 1
+
+ pool 1 pg_num 8
+ 1.0 [0,2,1] 0
+ 1.1 [2,0,1] 2
+ 1.2 [0,1,2] 0
+ 1.3 [2,0,1] 2
+ 1.4 [0,2,1] 0
+ 1.5 [0,2,1] 0
+ 1.6 [0,1,2] 0
+ 1.7 [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 1 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
+
+ * average, 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
+
+To simulate the active balancer in upmap mode::
+
+ osdmaptool --upmap upmaps.out --upmap-active --upmap-deviation 6 --upmap-max 11 osdmap
+
+ osdmaptool: osdmap file 'osdmap'
+ writing upmap command output to: upmaps.out
+ checking for upmap cleanups
+ upmap, max-count 11, max deviation 6
+ pools movies photos metadata data
+ prepared 11/11 changes
+ Time elapsed 0.00310404 secs
+ pools movies photos metadata data
+ prepared 11/11 changes
+ Time elapsed 0.00283402 secs
+ pools data metadata movies photos
+ prepared 11/11 changes
+ Time elapsed 0.003122 secs
+ pools photos metadata data movies
+ prepared 11/11 changes
+ Time elapsed 0.00324372 secs
+ pools movies metadata data photos
+ prepared 1/11 changes
+ Time elapsed 0.00222609 secs
+ pools data movies photos metadata
+ prepared 0/11 changes
+ Time elapsed 0.00209916 secs
+ Unable to find further optimization, or distribution is already perfect
+ osd.0 pgs 41
+ osd.1 pgs 42
+ osd.2 pgs 42
+ osd.3 pgs 41
+ osd.4 pgs 46
+ osd.5 pgs 39
+ osd.6 pgs 39
+ osd.7 pgs 43
+ osd.8 pgs 41
+ osd.9 pgs 46
+ osd.10 pgs 46
+ osd.11 pgs 46
+ osd.12 pgs 46
+ osd.13 pgs 41
+ osd.14 pgs 40
+ osd.15 pgs 40
+ osd.16 pgs 39
+ osd.17 pgs 46
+ osd.18 pgs 46
+ osd.19 pgs 39
+ osd.20 pgs 42
+ Total time elapsed 0.0167765 secs, 5 rounds
+
+To simulate the active balancer in read mode, first make sure capacity is balanced
+by running the balancer in upmap mode. Then, balance the reads on a replicated pool with::
+
+ osdmaptool osdmap --read read.out --read-pool <pool name>
+
+ ./bin/osdmaptool: osdmap file 'om'
+ writing upmap command output to: read.out
+
+ ---------- BEFORE ------------
+ osd.0 | primary affinity: 1 | number of prims: 3
+ osd.1 | primary affinity: 1 | number of prims: 10
+ osd.2 | primary affinity: 1 | number of prims: 3
+
+ read_balance_score of 'cephfs.a.meta': 1.88
+
+
+ ---------- AFTER ------------
+ osd.0 | primary affinity: 1 | number of prims: 5
+ osd.1 | primary affinity: 1 | number of prims: 5
+ osd.2 | primary affinity: 1 | number of prims: 6
+
+ read_balance_score of 'cephfs.a.meta': 1.13
+
+
+ num changes: 5
+
+Availability
+============
+
+**osdmaptool** is part of Ceph, a massively scalable, open-source, distributed storage system. Please
+refer to the Ceph documentation at https://docs.ceph.com for more
+information.
+
+
+See also
+========
+
+:doc:`ceph <ceph>`\(8),
+:doc:`crushtool <crushtool>`\(8),
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 09:33:46 +0000