[thumbnail="screenshot/gui-ceph-osd-status.png"]
-via GUI or via CLI as follows:
+You can create an OSD either via the {pve} web-interface, or via CLI using
+`pveceph`. For example:
[source,bash]
----
pveceph osd create /dev/sd[X]
----
-TIP: We recommend a Ceph cluster size, starting with 12 OSDs, distributed
-evenly among your, at least three nodes (4 OSDs on each node).
+TIP: We recommend a Ceph cluster with at least three nodes and a at least 12
+OSDs, evenly distributed among the nodes.
-If the disk was used before (eg. ZFS/RAID/OSD), to remove partition table, boot
-sector and any OSD leftover the following command should be sufficient.
+If the disk was in use before (for example, in a ZFS, or as OSD) you need to
+first zap all traces of that usage. To remove the partition table, boot
+sector and any other OSD leftover, you can use the following command:
[source,bash]
----
ceph-volume lvm zap /dev/sd[X] --destroy
----
-WARNING: The above command will destroy data on the disk!
+WARNING: The above command will destroy all data on the disk!
.Ceph Bluestore
**G**roups (`PG`, `pg_num`), a collection of objects.
-Create and edit Pools
+Create and Edit Pools
~~~~~~~~~~~~~~~~~~~~~
+You can create pools through command line or on the web-interface on each {pve}
+host under **Ceph -> Pools**.
+
[thumbnail="screenshot/gui-ceph-pools.png"]
When no options are given, we set a default of **128 PGs**, a **size of 3
-replicas** and a **min_size of 2 replicas** for serving objects in a degraded
-state.
-
-NOTE: The default number of PGs works for 2-5 disks. Ceph throws a
-'HEALTH_WARNING' if you have too few or too many PGs in your cluster.
+replicas** and a **min_size of 2 replicas**, to ensure no data loss occurs if
+any OSD fails.
WARNING: **Do not set a min_size of 1**. A replicated pool with min_size of 1
allows I/O on an object when it has only 1 replica which could lead to data
{cephdocs-url}/rados/operations/placement-groups/#automated-scaling] can
automatically scale the PG count for a pool in the background.
-You can create pools through command line or on the GUI on each PVE host under
-**Ceph -> Pools**.
-
+.Example for creating a pool over the CLI
[source,bash]
----
-pveceph pool create <name>
+pveceph pool create <name> --add_storages
----
-If you would like to automatically also get a storage definition for your pool,
-mark the checkbox "Add storages" in the GUI or use the command line option
-'--add_storages' at pool creation.
+TIP: If you would like to automatically also get a storage definition for your
+pool, keep the `Add storages' checkbox ticked in the web-interface, or use the
+command line option '--add_storages' at pool creation.
.Base Options
Name:: The name of the pool. This must be unique and can't be changed afterwards.
device-based rules.
# of PGs:: The number of placement groups footnoteref:[placement_groups] that
the pool should have at the beginning. Default: `128`.
-Traget Size:: The estimated amount of data expected in the pool. The PG
-autoscaler uses this size to estimate the optimal PG count.
Target Size Ratio:: The ratio of data that is expected in the pool. The PG
autoscaler uses the ratio relative to other ratio sets. It takes precedence
over the `target size` if both are set.
+Target Size:: The estimated amount of data expected in the pool. The PG
+autoscaler uses this size to estimate the optimal PG count.
Min. # of PGs:: The minimum number of placement groups. This setting is used to
fine-tune the lower bound of the PG count for that pool. The PG autoscaler
will not merge PGs below this threshold.
projects / pve-docs.git / blobdiff