rewrite and extend pct documentation

[pve-docs.git] / pveceph.adoc

diff --git a/pveceph.adoc b/pveceph.adoc
index d01ae462d0c49a4b2153de6060fe6259d2efee82..b3bbadfda7f5bd817195f029d8fbfc5aad87e0bd 100644 (file)
--- a/pveceph.adoc
+++ b/pveceph.adoc
@@ -18,8 +18,8 @@ DESCRIPTION
 -----------
 endif::manvolnum[]
 ifndef::manvolnum[]
-Manage Ceph Services on Proxmox VE Nodes
-========================================
+Deploy Hyper-Converged Ceph Cluster
+===================================
 :pve-toplevel:
 endif::manvolnum[]
 
@@ -101,7 +101,7 @@ services on the same network and may even break the {pve} cluster stack.
 
 Further, estimate your bandwidth needs. While one HDD might not saturate a 1 Gb
 link, multiple HDD OSDs per node can, and modern NVMe SSDs will even saturate
-10 Gbps of bandwidth quickly. Deploying a network capable of even more bandwith
+10 Gbps of bandwidth quickly. Deploying a network capable of even more bandwidth
 will ensure that it isn't your bottleneck and won't be anytime soon, 25, 40 or
 even 100 GBps are possible.
 
@@ -286,7 +286,7 @@ monitor the cluster. Since the Ceph luminous release at least one ceph-mgr
 footnote:[Ceph Manager https://docs.ceph.com/docs/{ceph_codename}/mgr/] daemon is
 required.
 
-[i[pveceph_create_mgr]]
+[[pveceph_create_mgr]]
 Create Manager
 ~~~~~~~~~~~~~~
 
@@ -378,7 +378,7 @@ pveceph osd create /dev/sd[X] -db_dev /dev/sd[Y] -wal_dev /dev/sd[Z]
 ----
 
 You can directly choose the size for those with the '-db_size' and '-wal_size'
-paremeters respectively. If they are not given the following values (in order)
+parameters respectively. If they are not given the following values (in order)
 will be used:
 
 * bluestore_block_{db,wal}_size from ceph configuration...
@@ -758,21 +758,23 @@ pveceph osd destroy <id>
 Replace the old disk with the new one and use the same procedure as described
 in xref:pve_ceph_osd_create[Create OSDs].
 
-Run fstrim (discard)
-~~~~~~~~~~~~~~~~~~~~
+Trim/Discard
+~~~~~~~~~~~~
 It is a good measure to run 'fstrim' (discard) regularly on VMs or containers.
 This releases data blocks that the filesystem isn’t using anymore. It reduces
-data usage and the resource load.
+data usage and resource load. Most modern operating systems issue such discard
+commands to their disks regularly. You only need to ensure that the Virtual
+Machines enable the xref:qm_hard_disk_discard[disk discard option].
 
 [[pveceph_scrub]]
 Scrub & Deep Scrub
 ~~~~~~~~~~~~~~~~~~
 Ceph ensures data integrity by 'scrubbing' placement groups. Ceph checks every
 object in a PG for its health. There are two forms of Scrubbing, daily
-(metadata compare) and weekly. The weekly reads the objects and uses checksums
-to ensure data integrity. If a running scrub interferes with business needs,
-you can adjust the time when scrubs footnote:[Ceph scrubbing
-https://docs.ceph.com/docs/{ceph_codename}/rados/configuration/osd-config-ref/#scrubbing]
+cheap metadata checks and weekly deep data checks. The weekly deep scrub reads
+the objects and uses checksums to ensure data integrity. If a running scrub
+interferes with business (performance) needs, you can adjust the time when
+scrubs footnote:[Ceph scrubbing https://docs.ceph.com/docs/{ceph_codename}/rados/configuration/osd-config-ref/#scrubbing]
 are executed.