[pve-devel] [PATCH pve-docs 1/2] pmxcfs: language and style fixup
Lorenz Stechauner
l.stechauner at proxmox.com
Tue Sep 14 09:48:17 CEST 2021
patch looks good to me in general. see inline for notes
On 13.09.21 18:00, Dylan Whyte wrote:
> minor language fixup
> replace usage of 'Proxmox VE' with '{pve}'
>
> Signed-off-by: Dylan Whyte <d.whyte at proxmox.com>
> ---
> pmxcfs.adoc | 62 ++++++++++++++++++++++++++---------------------------
> 1 file changed, 30 insertions(+), 32 deletions(-)
>
> diff --git a/pmxcfs.adoc b/pmxcfs.adoc
> index d4579a7..c0327a2 100644
> --- a/pmxcfs.adoc
> +++ b/pmxcfs.adoc
> @@ -30,17 +30,17 @@ cluster nodes using `corosync`. We use this to store all PVE related
> configuration files.
>
> Although the file system stores all data inside a persistent database
> -on disk, a copy of the data resides in RAM. That imposes restriction
> +on disk, a copy of the data resides in RAM. This imposes restrictions
> on the maximum size, which is currently 30MB. This is still enough to
> store the configuration of several thousand virtual machines.
>
> This system provides the following advantages:
>
> -* seamless replication of all configuration to all nodes in real time
> -* provides strong consistency checks to avoid duplicate VM IDs
> -* read-only when a node loses quorum
> -* automatic updates of the corosync cluster configuration to all nodes
> -* includes a distributed locking mechanism
> +* Seamless replication of all configuration to all nodes in real time
> +* Provides strong consistency checks to avoid duplicate VM IDs
> +* Read-only when a node loses quorum
> +* Automatic updates of the corosync cluster configuration to all nodes
> +* Includes a distributed locking mechanism
>
>
> POSIX Compatibility
> @@ -49,13 +49,13 @@ POSIX Compatibility
> The file system is based on FUSE, so the behavior is POSIX like. But
> some feature are simply not implemented, because we do not need them:
>
> -* you can just generate normal files and directories, but no symbolic
> +* You can just generate normal files and directories, but no symbolic
> links, ...
>
> -* you can't rename non-empty directories (because this makes it easier
> +* You can't rename non-empty directories (because this makes it easier
> to guarantee that VMIDs are unique).
>
> -* you can't change file permissions (permissions are based on path)
> +* You can't change file permissions (permissions are based on paths)
>
> * `O_EXCL` creates were not atomic (like old NFS)
>
> @@ -67,13 +67,11 @@ File Access Rights
>
> All files and directories are owned by user `root` and have group
> `www-data`. Only root has write permissions, but group `www-data` can
> -read most files. Files below the following paths:
> +read most files. Files below the following paths are only accessible by root:
>
> /etc/pve/priv/
> /etc/pve/nodes/${NAME}/priv/
>
> -are only accessible by root.
> -
>
> Technology
> ----------
> @@ -157,25 +155,25 @@ And disable verbose syslog messages with:
> Recovery
> --------
>
> -If you have major problems with your Proxmox VE host, e.g. hardware
> -issues, it could be helpful to just copy the pmxcfs database file
> -`/var/lib/pve-cluster/config.db` and move it to a new Proxmox VE
> +If you have major problems with your {pve} host, for example hardware
> +issues, it could be helpful to copy the pmxcfs database file
> +`/var/lib/pve-cluster/config.db`, and move it to a new {pve}
> host. On the new host (with nothing running), you need to stop the
> -`pve-cluster` service and replace the `config.db` file (needed permissions
> -`0600`). Second, adapt `/etc/hostname` and `/etc/hosts` according to the
> -lost Proxmox VE host, then reboot and check. (And don't forget your
> -VM/CT data)
> +`pve-cluster` service and replace the `config.db` file (required permissions
> +`0600`). Following this, adapt `/etc/hostname` and `/etc/hosts` according to the
> +lost {pve} host, then reboot and check (and don't forget your
> +VM/CT data).
>
>
> -Remove Cluster configuration
> +Remove Cluster Configuration
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> -The recommended way is to reinstall the node after you removed it from
> -your cluster. This makes sure that all secret cluster/ssh keys and any
> +The recommended way is to reinstall the node after you remove it from
> +your cluster. This ensures that all secret cluster/ssh keys and any
> shared configuration data is destroyed.
>
> In some cases, you might prefer to put a node back to local mode without
> -reinstall, which is described in
> +reinstalling, which is described in
> <<pvecm_separate_node_without_reinstall,Separate A Node Without Reinstalling>>
>
>
> @@ -183,28 +181,28 @@ Recovering/Moving Guests from Failed Nodes
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> For the guest configuration files in `nodes/<NAME>/qemu-server/` (VMs) and
> -`nodes/<NAME>/lxc/` (containers), {pve} sees the containing node `<NAME>` as
> +`nodes/<NAME>/lxc/` (containers), {pve} sees the containing node `<NAME>` as the
> owner of the respective guest. This concept enables the usage of local locks
> instead of expensive cluster-wide locks for preventing concurrent guest
> configuration changes.
>
> -As a consequence, if the owning node of a guest fails (e.g., because of a power
> -outage, fencing event, ..), a regular migration is not possible (even if all
> -the disks are located on shared storage) because such a local lock on the
> +As a consequence, if the owning node of a guest fails (for example, due to a power
> +outage, fencing event, etc.), a regular migration is not possible (even if all
> +the disks are located on shared storage), because such a local lock on the
> (dead) owning node is unobtainable. This is not a problem for HA-managed
> guests, as {pve}'s High Availability stack includes the necessary
> (cluster-wide) locking and watchdog functionality to ensure correct and
> automatic recovery of guests from fenced nodes.
>
> If a non-HA-managed guest has only shared disks (and no other local resources
> -which are only available on the failed node are configured), a manual recovery
> +which are only available on the failed node), a manual recovery
> is possible by simply moving the guest configuration file from the failed
> -node's directory in `/etc/pve/` to an alive node's directory (which changes the
> +node's directory in `/etc/pve/` to an online node's directory (which changes the
> logical owner or location of the guest).
>
> For example, recovering the VM with ID `100` from a dead `node1` to another
> -node `node2` works with the following command executed when logged in as root
> -on any member node of the cluster:
> +node `node2` works by running the following command as root on any member node
> +of the cluster:
>
> mv /etc/pve/nodes/node1/qemu-server/100.conf /etc/pve/nodes/node2/
>
> @@ -213,7 +211,7 @@ that the failed source node is really powered off/fenced. Otherwise {pve}'s
> locking principles are violated by the `mv` command, which can have unexpected
> consequences.
>
> -WARNING: Guest with local disks (or other local resources which are only
> +WARNING: Guests with local disks (or other local resources which are only
> available on the dead node) are not recoverable like this. Either wait for the
maybe write offline instead of dead? (like above, alive -> online)
> failed node to rejoin the cluster or restore such guests from backups.
>
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