[pbs-devel] [PATCH proxmox-backup] docs: language and formatting fixup

Dylan Whyte d.whyte at proxmox.com
Mon Oct 11 17:15:19 CEST 2021


Some minor langague and formatting fixes to sections: Proxmox VE
Integration, pxar Command Line Tool, Managing Remotes, Maintenance
Tasks, Host System Administration, Network Management, and Technical
Overview.

Signed-off-by: Dylan Whyte <d.whyte at proxmox.com>
---
 docs/local-zfs.rst                        | 133 ++++++++++++----------
 docs/maintenance.rst                      |  54 ++++-----
 docs/managing-remotes.rst                 |  23 ++--
 docs/network-management.rst               |   3 +-
 docs/proxmox-backup-proxy/description.rst |   2 +-
 docs/pve-integration.rst                  |  16 +--
 docs/pxar/description.rst                 |  52 ++++-----
 docs/sysadmin.rst                         |   8 +-
 docs/technical-overview.rst               | 130 ++++++++++-----------
 9 files changed, 221 insertions(+), 200 deletions(-)

diff --git a/docs/local-zfs.rst b/docs/local-zfs.rst
index f36aefe8..32af860f 100644
--- a/docs/local-zfs.rst
+++ b/docs/local-zfs.rst
@@ -4,17 +4,17 @@
 ZFS on Linux
 ------------
 
-ZFS is a combined file system and logical volume manager designed by
+ZFS is a combined file system and logical volume manager, designed by
 Sun Microsystems. There is no need to manually compile ZFS modules - all
 packages are included.
 
 By using ZFS, it's possible to achieve maximum enterprise features with
-low budget hardware, but also high performance systems by leveraging
-SSD caching or even SSD only setups. ZFS can replace cost intense
-hardware raid cards by moderate CPU and memory load combined with easy
+low budget hardware, and also high performance systems by leveraging
+SSD caching or even SSD only setups. ZFS can replace expensive
+hardware raid cards with moderate CPU and memory load, combined with easy
 management.
 
-General ZFS advantages
+General advantages of ZFS:
 
 * Easy configuration and management with GUI and CLI.
 * Reliable
@@ -34,18 +34,18 @@ General ZFS advantages
 Hardware
 ~~~~~~~~~
 
-ZFS depends heavily on memory, so you need at least 8GB to start. In
-practice, use as much you can get for your hardware/budget. To prevent
+ZFS depends heavily on memory, so it's recommended to have at least 8GB to
+start. In practice, use as much you can get for your hardware/budget. To prevent
 data corruption, we recommend the use of high quality ECC RAM.
 
 If you use a dedicated cache and/or log disk, you should use an
-enterprise class SSD (e.g. Intel SSD DC S3700 Series). This can
+enterprise class SSD (for example, Intel SSD DC S3700 Series). This can
 increase the overall performance significantly.
 
-IMPORTANT: Do not use ZFS on top of hardware controller which has its
+IMPORTANT: Do not use ZFS on top of a hardware controller which has its
 own cache management. ZFS needs to directly communicate with disks. An
-HBA adapter is the way to go, or something like LSI controller flashed
-in ``IT`` mode.
+HBA adapter or something like an LSI controller flashed in ``IT`` mode is
+recommended.
 
 
 ZFS Administration
@@ -53,7 +53,7 @@ ZFS Administration
 
 This section gives you some usage examples for common tasks. ZFS
 itself is really powerful and provides many options. The main commands
-to manage ZFS are `zfs` and `zpool`. Both commands come with great
+to manage ZFS are `zfs` and `zpool`. Both commands come with extensive
 manual pages, which can be read with:
 
 .. code-block:: console
@@ -123,7 +123,7 @@ Create a new pool with cache (L2ARC)
 It is possible to use a dedicated cache drive partition to increase
 the performance (use SSD).
 
-As `<device>` it is possible to use more devices, like it's shown in
+For `<device>`, you can use multiple devices, as is shown in
 "Create a new pool with RAID*".
 
 .. code-block:: console
@@ -136,7 +136,7 @@ Create a new pool with log (ZIL)
 It is possible to use a dedicated cache drive partition to increase
 the performance (SSD).
 
-As `<device>` it is possible to use more devices, like it's shown in
+For `<device>`, you can use multiple devices, as is shown in
 "Create a new pool with RAID*".
 
 .. code-block:: console
@@ -146,8 +146,9 @@ As `<device>` it is possible to use more devices, like it's shown in
 Add cache and log to an existing pool
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-If you have a pool without cache and log. First partition the SSD in
-2 partition with `parted` or `gdisk`
+You can add cache and log devices to a pool after its creation. In this example,
+we will use a single drive for both cache and log. First, you need to create
+2 partitions on the SSD with `parted` or `gdisk`
 
 .. important:: Always use GPT partition tables.
 
@@ -171,12 +172,12 @@ Changing a failed device
 Changing a failed bootable device
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Depending on how Proxmox Backup was installed it is either using `grub` or `systemd-boot`
-as bootloader.
+Depending on how Proxmox Backup was installed, it is either using `grub` or
+`systemd-boot` as a bootloader.
 
-The first steps of copying the partition table, reissuing GUIDs and replacing
-the ZFS partition are the same. To make the system bootable from the new disk,
-different steps are needed which depend on the bootloader in use.
+In either case, the first steps of copying the partition table, reissuing GUIDs
+and replacing the ZFS partition are the same. To make the system bootable from
+the new disk, different steps are needed which depend on the bootloader in use.
 
 .. code-block:: console
 
@@ -207,7 +208,7 @@ Usually `grub.cfg` is located in `/boot/grub/grub.cfg`
   # grub-mkconfig -o /path/to/grub.cfg
 
 
-Activate E-Mail Notification
+Activate e-mail notification
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 ZFS comes with an event daemon, which monitors events generated by the
@@ -219,24 +220,24 @@ and you can install it using `apt-get`:
 
   # apt-get install zfs-zed
 
-To activate the daemon it is necessary to edit `/etc/zfs/zed.d/zed.rc` with your
-favorite editor, and uncomment the `ZED_EMAIL_ADDR` setting:
+To activate the daemon, it is necessary to to uncomment the ZED_EMAIL_ADDR
+setting, in the file `/etc/zfs/zed.d/zed.rc`.
 
 .. code-block:: console
 
   ZED_EMAIL_ADDR="root"
 
-Please note Proxmox Backup forwards mails to `root` to the email address
+Please note that Proxmox Backup forwards mails to `root` to the email address
 configured for the root user.
 
 IMPORTANT: The only setting that is required is `ZED_EMAIL_ADDR`. All
 other settings are optional.
 
-Limit ZFS Memory Usage
+Limit ZFS memory usage
 ^^^^^^^^^^^^^^^^^^^^^^
 
 It is good to use at most 50 percent (which is the default) of the
-system memory for ZFS ARC to prevent performance shortage of the
+system memory for ZFS ARC, to prevent performance degradation of the
 host. Use your preferred editor to change the configuration in
 `/etc/modprobe.d/zfs.conf` and insert:
 
@@ -244,27 +245,42 @@ host. Use your preferred editor to change the configuration in
 
   options zfs zfs_arc_max=8589934592
 
-This example setting limits the usage to 8GB.
+The above example limits the usage to 8 GiB ('8 * 2^30^').
 
-.. IMPORTANT:: If your root file system is ZFS you must update your initramfs every time this value changes:
+.. IMPORTANT:: In case your desired `zfs_arc_max` value is lower than or equal
+   to `zfs_arc_min` (which defaults to 1/32 of the system memory), `zfs_arc_max`
+   will be ignored. Thus, for it to work in this case, you must set
+   `zfs_arc_min` to at most `zfs_arc_max - 1`. This would require updating the
+   configuration in `/etc/modprobe.d/zfs.conf`, with:
+
+.. code-block:: console
+  options zfs zfs_arc_min=8589934591
+  options zfs zfs_arc_max=8589934592
+
+This example setting limits the usage to 8 GiB ('8 * 2^30^') on
+systems with more than 256 GiB of total memory, where simply setting
+`zfs_arc_max` alone would not work.
+
+.. IMPORTANT:: If your root file system is ZFS, you must update your initramfs
+   every time this value changes.
 
 .. code-block:: console
 
   # update-initramfs -u
 
 
-SWAP on ZFS
+Swap on ZFS
 ^^^^^^^^^^^
 
-Swap-space created on a zvol may generate some troubles, like blocking the
+Swap-space created on a zvol may cause some issues, such as blocking the
 server or generating a high IO load, often seen when starting a Backup
 to an external Storage.
 
-We strongly recommend to use enough memory, so that you normally do not
+We strongly recommend using enough memory, so that you normally do not
 run into low memory situations. Should you need or want to add swap, it is
-preferred to create a partition on a physical disk and use it as swap device.
+preferred to create a partition on a physical disk and use it as a swap device.
 You can leave some space free for this purpose in the advanced options of the
-installer. Additionally, you can lower the `swappiness` value. 
+installer. Additionally, you can lower the `swappiness` value.
 A good value for servers is 10:
 
 .. code-block:: console
@@ -291,7 +307,7 @@ an editor of your choice and add the following line:
    vm.swappiness = 100  The kernel will swap aggressively.
   ====================  ===============================================================
 
-ZFS Compression
+ZFS compression
 ^^^^^^^^^^^^^^^
 
 To activate compression:
@@ -300,10 +316,11 @@ To activate compression:
   # zpool set compression=lz4 <pool>
 
 We recommend using the `lz4` algorithm, since it adds very little CPU overhead.
-Other algorithms such as `lzjb` and `gzip-N` (where `N` is an integer `1-9` representing
-the compression ratio, 1 is fastest and 9 is best compression) are also available.
-Depending on the algorithm and how compressible the data is, having compression enabled can even increase
-I/O performance.
+Other algorithms such as `lzjb` and `gzip-N` (where `N` is an integer from `1-9`
+representing the compression ratio, where 1 is fastest and 9 is best
+compression) are also available. Depending on the algorithm and how
+compressible the data is, having compression enabled can even increase I/O
+performance.
 
 You can disable compression at any time with:
 .. code-block:: console
@@ -314,26 +331,26 @@ Only new blocks will be affected by this change.
 
 .. _local_zfs_special_device:
 
-ZFS Special Device
+ZFS special device
 ^^^^^^^^^^^^^^^^^^
 
-Since version 0.8.0 ZFS supports `special` devices. A `special` device in a
+Since version 0.8.0, ZFS supports `special` devices. A `special` device in a
 pool is used to store metadata, deduplication tables, and optionally small
 file blocks.
 
 A `special` device can improve the speed of a pool consisting of slow spinning
-hard disks with a lot of metadata changes. For example workloads that involve
+hard disks with a lot of metadata changes. For example, workloads that involve
 creating, updating or deleting a large number of files will benefit from the
 presence of a `special` device. ZFS datasets can also be configured to store
-whole small files on the `special` device which can further improve the
+small files on the `special` device, which can further improve the
 performance. Use fast SSDs for the `special` device.
 
 .. IMPORTANT:: The redundancy of the `special` device should match the one of the
-  pool, since the `special` device is a point of failure for the whole pool.
+  pool, since the `special` device is a point of failure for the entire pool.
 
 .. WARNING:: Adding a `special` device to a pool cannot be undone!
 
-Create a pool with `special` device and RAID-1:
+To create a pool with `special` device and RAID-1:
 
 .. code-block:: console
 
@@ -346,8 +363,8 @@ Adding a `special` device to an existing pool with RAID-1:
   # zpool add <pool> special mirror <device1> <device2>
 
 ZFS datasets expose the `special_small_blocks=<size>` property. `size` can be
-`0` to disable storing small file blocks on the `special` device or a power of
-two in the range between `512B` to `128K`. After setting the property new file
+`0` to disable storing small file blocks on the `special` device, or a power of
+two in the range between `512B` to `128K`. After setting this property, new file
 blocks smaller than `size` will be allocated on the `special` device.
 
 .. IMPORTANT:: If the value for `special_small_blocks` is greater than or equal to
@@ -355,10 +372,10 @@ blocks smaller than `size` will be allocated on the `special` device.
   the `special` device, so be careful!
 
 Setting the `special_small_blocks` property on a pool will change the default
-value of that property for all child ZFS datasets (for example all containers
+value of that property for all child ZFS datasets (for example, all containers
 in the pool will opt in for small file blocks).
 
-Opt in for all file smaller than 4K-blocks pool-wide:
+Opt in for all files smaller than 4K-blocks pool-wide:
 
 .. code-block:: console
 
@@ -379,10 +396,15 @@ Opt out from small file blocks for a single dataset:
 Troubleshooting
 ^^^^^^^^^^^^^^^
 
-Corrupted cachefile
+Corrupt cache file
+""""""""""""""""""
+
+`zfs-import-cache.service` imports ZFS pools using the ZFS cache file. If this
+file becomes corrupted, the service won't be able to import the pools that it's
+unable to read from it.
 
-In case of a corrupted ZFS cachefile, some volumes may not be mounted during
-boot until mounted manually later.
+As a result, in case of a corrupted ZFS cache file, some volumes may not be
+mounted during boot and must be mounted manually later.
 
 For each pool, run:
 
@@ -390,16 +412,13 @@ For each pool, run:
 
   # zpool set cachefile=/etc/zfs/zpool.cache POOLNAME
 
-and afterwards update the `initramfs` by running:
+then, update the `initramfs` by running:
 
 .. code-block:: console
 
   # update-initramfs -u -k all
 
-and finally reboot your node.
-
-Sometimes the ZFS cachefile can get corrupted, and `zfs-import-cache.service`
-doesn't import the pools that aren't present in the cachefile.
+and finally, reboot the node.
 
 Another workaround to this problem is enabling the `zfs-import-scan.service`,
 which searches and imports pools via device scanning (usually slower).
diff --git a/docs/maintenance.rst b/docs/maintenance.rst
index 15b313d0..8be5b666 100644
--- a/docs/maintenance.rst
+++ b/docs/maintenance.rst
@@ -14,15 +14,15 @@ following retention options are available:
 
 ``keep-hourly <N>``
   Keep backups for the last ``<N>`` hours. If there is more than one
-  backup for a single hour, only the latest is kept.
+  backup for a single hour, only the latest is retained.
 
 ``keep-daily <N>``
   Keep backups for the last ``<N>`` days. If there is more than one
-  backup for a single day, only the latest is kept.
+  backup for a single day, only the latest is retained.
 
 ``keep-weekly <N>``
   Keep backups for the last ``<N>`` weeks. If there is more than one
-  backup for a single week, only the latest is kept.
+  backup for a single week, only the latest is retained.
 
   .. note:: Weeks start on Monday and end on Sunday. The software
      uses the `ISO week date`_ system and handles weeks at
@@ -30,17 +30,17 @@ following retention options are available:
 
 ``keep-monthly <N>``
   Keep backups for the last ``<N>`` months. If there is more than one
-  backup for a single month, only the latest is kept.
+  backup for a single month, only the latest is retained.
 
 ``keep-yearly <N>``
   Keep backups for the last ``<N>`` years. If there is more than one
-  backup for a single year, only the latest is kept.
+  backup for a single year, only the latest is retained.
 
 The retention options are processed in the order given above. Each option
 only covers backups within its time period. The next option does not take care
 of already covered backups. It will only consider older backups.
 
-Unfinished and incomplete backups will be removed by the prune command unless
+Unfinished and incomplete backups will be removed by the prune command, unless
 they are newer than the last successful backup. In this case, the last failed
 backup is retained.
 
@@ -48,7 +48,7 @@ Prune Simulator
 ^^^^^^^^^^^^^^^
 
 You can use the built-in `prune simulator <prune-simulator/index.html>`_
-to explore the effect of different retetion options with various backup
+to explore the effect of different retention options with various backup
 schedules.
 
 Manual Pruning
@@ -59,10 +59,10 @@ Manual Pruning
   :align: right
   :alt: Prune and garbage collection options
 
-To access pruning functionality for a specific backup group, you can use the
-prune command line option discussed in :ref:`backup-pruning`, or navigate to
-the **Content** tab of the datastore and click the scissors icon in the
-**Actions** column of the relevant backup group.
+To manually prune a specific backup group, you can use
+``proxmox-backup-client``'s ``prune`` subcommand, discussed in
+:ref:`backup-pruning`, or navigate to the **Content** tab of the datastore and
+click the scissors icon in the **Actions** column of the relevant backup group.
 
 Prune Schedules
 ^^^^^^^^^^^^^^^
@@ -81,7 +81,7 @@ Retention Settings Example
 ^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 The backup frequency and retention of old backups may depend on how often data
-changes, and how important an older state may be, in a specific work load.
+changes and how important an older state may be in a specific workload.
 When backups act as a company's document archive, there may also be legal
 requirements for how long backup snapshots must be kept.
 
@@ -125,8 +125,8 @@ start garbage collection on an entire datastore and the ``status`` subcommand to
 see attributes relating to the :ref:`garbage collection <client_garbage-collection>`.
 
 This functionality can also be accessed in the GUI, by navigating to **Prune &
-GC** from the top panel. From here, you can edit the schedule at which garbage
-collection runs and manually start the operation.
+GC** from the top panel of a datastore. From here, you can edit the schedule at
+which garbage collection runs and manually start the operation.
 
 
 .. _maintenance_verification:
@@ -139,13 +139,13 @@ Verification
   :align: right
   :alt: Adding a verify job
 
-Proxmox Backup offers various verification options to ensure that backup data is
-intact.  Verification is generally carried out through the creation of verify
-jobs. These are scheduled tasks that run verification at a given interval (see
-:ref:`calendar-event-scheduling`). With these, you can set whether already verified
-snapshots are ignored, as well as set a time period, after which verified jobs
-are checked again. The interface for creating verify jobs can be found under the
-**Verify Jobs** tab of the datastore.
+Proxmox Backup Server offers various verification options to ensure that backup
+data is intact. Verification is generally carried out through the creation of
+verify jobs. These are scheduled tasks that run verification at a given interval
+(see :ref:`calendar-event-scheduling`). With these, you can also set whether
+already verified snapshots are ignored, as well as set a time period, after
+which snapshots are checked again. The interface for creating verify jobs can be
+found under the **Verify Jobs** tab of the datastore.
 
 .. Note:: It is recommended that you reverify all backups at least monthly, even
   if a previous verification was successful. This is because physical drives
@@ -158,9 +158,9 @@ are checked again. The interface for creating verify jobs can be found under the
   data.
 
 Aside from using verify jobs, you can also run verification manually on entire
-datastores, backup groups, or snapshots. To do this, navigate to the **Content**
-tab of the datastore and either click *Verify All*, or select the *V.* icon from
-the *Actions* column in the table.
+datastores, backup groups or snapshots. To do this, navigate to the **Content**
+tab of the datastore and either click *Verify All* or select the *V.* icon from
+the **Actions** column in the table.
 
 .. _maintenance_notification:
 
@@ -170,8 +170,8 @@ Notifications
 Proxmox Backup Server can send you notification emails about automatically
 scheduled verification, garbage-collection and synchronization tasks results.
 
-By default, notifications are send to the email address configured for the
-`root at pam` user. You can set that user for each datastore.
+By default, notifications are sent to the email address configured for the
+`root at pam` user. You can instead set this user for each datastore.
 
 You can also change the level of notification received per task type, the
 following options are available:
@@ -179,6 +179,6 @@ following options are available:
 * Always: send a notification for any scheduled task, independent of the
   outcome
 
-* Errors: send a notification for any scheduled task resulting in an error
+* Errors: send a notification for any scheduled task that results in an error
 
 * Never: do not send any notification at all
diff --git a/docs/managing-remotes.rst b/docs/managing-remotes.rst
index 88ab3ba2..ccb7313e 100644
--- a/docs/managing-remotes.rst
+++ b/docs/managing-remotes.rst
@@ -17,8 +17,8 @@ configuration information for remotes is stored in the file
   :align: right
   :alt: Add a remote
 
-To add a remote, you need its hostname or IP, a userid and password on the
-remote, and its certificate fingerprint. To get the fingerprint, use the
+To add a remote, you need its hostname or IP address, a userid and password on
+the remote, and its certificate fingerprint. To get the fingerprint, use the
 ``proxmox-backup-manager cert info`` command on the remote, or navigate to
 **Dashboard** in the remote's web interface and select **Show Fingerprint**.
 
@@ -60,12 +60,13 @@ Sync Jobs
 
 Sync jobs are configured to pull the contents of a datastore on a **Remote** to
 a local datastore. You can manage sync jobs in the web interface, from the
-**Sync Jobs** tab of the datastore which you'd like to set one up for, or using
-the ``proxmox-backup-manager sync-job`` command.  The configuration information
-for sync jobs is stored at ``/etc/proxmox-backup/sync.cfg``. To create a new
-sync job, click the add button in the GUI, or use the ``create`` subcommand.
-After creating a sync job, you can either start it manually from the GUI or
-provide it with a schedule (see :ref:`calendar-event-scheduling`) to run regularly.
+**Sync Jobs** tab of the **Datastore** panel or from that of the Datastore
+itself. Alternatively, you can manage them with the ``proxmox-backup-manager
+sync-job`` command. The configuration information for sync jobs is stored at
+``/etc/proxmox-backup/sync.cfg``. To create a new sync job, click the add button
+in the GUI, or use the ``create`` subcommand. After creating a sync job, you can
+either start it manually from the GUI or provide it with a schedule (see
+:ref:`calendar-event-scheduling`) to run regularly.
 
 .. code-block:: console
 
@@ -79,14 +80,14 @@ provide it with a schedule (see :ref:`calendar-event-scheduling`) to run regular
   └────────────┴───────┴────────┴──────────────┴───────────┴─────────┘
   # proxmox-backup-manager sync-job remove pbs2-local
 
-For setting up sync jobs, the configuring user needs the following permissions:
+To set up sync jobs, the configuring user needs the following permissions:
 
 #. ``Remote.Read`` on the ``/remote/{remote}/{remote-store}`` path
-#. at least ``Datastore.Backup`` on the local target datastore (``/datastore/{store}``)
+#. At least ``Datastore.Backup`` on the local target datastore (``/datastore/{store}``)
 
 If the ``remove-vanished`` option is set, ``Datastore.Prune`` is required on
 the local datastore as well. If the ``owner`` option is not set (defaulting to
-``root at pam``) or set to something other than the configuring user,
+``root at pam``) or is set to something other than the configuring user,
 ``Datastore.Modify`` is required as well.
 
 .. note:: A sync job can only sync backup groups that the configured remote's
diff --git a/docs/network-management.rst b/docs/network-management.rst
index 4b7ac75d..d6d84651 100644
--- a/docs/network-management.rst
+++ b/docs/network-management.rst
@@ -82,7 +82,8 @@ is:
 .. note:: This command and corresponding GUI button rely on the ``ifreload``
   command, from the package ``ifupdown2``. This package is included within the
   Proxmox Backup Server installation, however, you may have to install it yourself,
-  if you have installed Proxmox Backup Server on top of Debian or Proxmox VE.
+  if you have installed Proxmox Backup Server on top of Debian or a Proxmox VE
+  version prior to version 7.
 
 You can also configure DNS settings, from the **DNS** section
 of **Configuration** or by using the ``dns`` subcommand of
diff --git a/docs/proxmox-backup-proxy/description.rst b/docs/proxmox-backup-proxy/description.rst
index 34e620e8..2fb55020 100644
--- a/docs/proxmox-backup-proxy/description.rst
+++ b/docs/proxmox-backup-proxy/description.rst
@@ -1,5 +1,5 @@
 This daemon exposes the whole Proxmox Backup Server API on TCP port
 8007 using HTTPS. It runs as user ``backup`` and has very limited
-permissions. Operation requiring more permissions are forwarded to
+permissions. Operations requiring more permissions are forwarded to
 the local ``proxmox-backup`` service.
 
diff --git a/docs/pve-integration.rst b/docs/pve-integration.rst
index 35d2adfd..2fe5c66a 100644
--- a/docs/pve-integration.rst
+++ b/docs/pve-integration.rst
@@ -3,8 +3,8 @@
 `Proxmox VE`_ Integration
 -------------------------
 
-A Proxmox Backup Server can be integrated into a Proxmox VE setup by adding the
-former as a storage in a Proxmox VE standalone or cluster setup.
+Proxmox Backup Server can be integrated into a Proxmox VE standalone or cluster
+setup, by adding it as a storage in Proxmox VE.
 
 See also the `Proxmox VE Storage - Proxmox Backup Server
 <https://pve.proxmox.com/pve-docs/pve-admin-guide.html#storage_pbs>`_ section
@@ -14,8 +14,8 @@ of the Proxmox VE Administration Guide for Proxmox VE specific documentation.
 Using the Proxmox VE Web-Interface
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Proxmox VE has native API and web-interface integration of Proxmox Backup
-Server since the `Proxmox VE 6.3 release
+Proxmox VE has native API and web interface integration of Proxmox Backup
+Server as of `Proxmox VE 6.3
 <https://pve.proxmox.com/wiki/Roadmap#Proxmox_VE_6.3>`_.
 
 A Proxmox Backup Server can be added under ``Datacenter -> Storage``.
@@ -24,8 +24,8 @@ Using the Proxmox VE Command-Line
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 You need to define a new storage with type 'pbs' on your `Proxmox VE`_
-node. The following example uses ``store2`` as storage name, and
-assumes the server address is ``localhost``, and you want to connect
+node. The following example uses ``store2`` as the storage's name, and
+assumes the server address is ``localhost`` and you want to connect
 as ``user1 at pbs``.
 
 .. code-block:: console
@@ -33,7 +33,7 @@ as ``user1 at pbs``.
   # pvesm add pbs store2 --server localhost --datastore store2
   # pvesm set store2 --username user1 at pbs --password <secret>
 
-.. note:: If you would rather not pass your password as plain text, you can pass
+.. note:: If you would rather not enter your password as plain text, you can pass
   the ``--password`` parameter, without any arguments. This will cause the
   program to prompt you for a password upon entering the command.
 
@@ -53,7 +53,7 @@ relationship:
 
   # pvesm set store2 --fingerprint  64:d3:ff:3a:50:38:53:5a:9b:f7:50:...:ab:fe
 
-After that you should be able to see storage status with:
+After that, you should be able to view storage status with:
 
 .. code-block:: console
 
diff --git a/docs/pxar/description.rst b/docs/pxar/description.rst
index 770d240c..bf802809 100644
--- a/docs/pxar/description.rst
+++ b/docs/pxar/description.rst
@@ -1,12 +1,12 @@
-``pxar`` is a command line utility to create and manipulate archives in the
+``pxar`` is a command line utility for creating and manipulating archives in the
 :ref:`pxar-format`.
 It is inspired by `casync file archive format
 <http://0pointer.net/blog/casync-a-tool-for-distributing-file-system-images.html>`_,
 which caters to a similar use-case.
 The ``.pxar`` format is adapted to fulfill the specific needs of the Proxmox
-Backup Server, for example, efficient storage of hardlinks.
-The format is designed to reduce storage space needed on the server by achieving
-a high level of deduplication.
+Backup Server, for example, efficient storage of hard links.
+The format is designed to reduce the required storage on the server by
+achieving a high level of deduplication.
 
 Creating an Archive
 ^^^^^^^^^^^^^^^^^^^
@@ -24,10 +24,10 @@ This will create a new archive called ``archive.pxar`` with the contents of the
     the same name is already present in the target folder, the creation will
     fail.
 
-By default, ``pxar`` will skip certain mountpoints and will not follow device
+By default, ``pxar`` will skip certain mount points and will not follow device
 boundaries. This design decision is based on the primary use case of creating
-archives for backups. It makes sense to not back up the contents of certain
-temporary or system specific files.
+archives for backups. It makes sense to ignore the contents of certain
+temporary or system specific files in a backup.
 To alter this behavior and follow device boundaries, use the
 ``--all-file-systems`` flag.
 
@@ -41,40 +41,38 @@ by running:
 
     # pxar create archive.pxar /path/to/source --exclude '**/*.txt'
 
-Be aware that the shell itself will try to expand all of the glob patterns before
-invoking ``pxar``.
-In order to avoid this, all globs have to be quoted correctly.
+Be aware that the shell itself will try to expand glob patterns before invoking
+``pxar``. In order to avoid this, all globs have to be quoted correctly.
 
 It is possible to pass the ``--exclude`` parameter multiple times, in order to
 match more than one pattern. This allows you to use more complex
-file exclusion/inclusion behavior. However, it is recommended to use
+file inclusion/exclusion behavior. However, it is recommended to use
 ``.pxarexclude`` files instead for such cases.
 
-For example you might want to exclude all ``.txt`` files except for a specific
-one from the archive. This is achieved via the negated match pattern, prefixed
-by ``!``.
-All the glob patterns are relative to the ``source`` directory.
+For example you might want to exclude all ``.txt`` files except a specific
+one from the archive. This would be achieved via the negated match pattern,
+prefixed by ``!``.  All the glob patterns are relative to the ``source``
+directory.
 
 .. code-block:: console
 
     # pxar create archive.pxar /path/to/source --exclude '**/*.txt' --exclude '!/folder/file.txt'
 
-.. NOTE:: The order of the glob match patterns matters as later ones override
-    previous ones. Permutations of the same patterns lead to different results.
+.. NOTE:: The order of the glob match patterns matters, as later ones override
+   earlier ones. Permutations of the same patterns lead to different results.
 
 ``pxar`` will store the list of glob match patterns passed as parameters via the
-command line, in a file called ``.pxarexclude-cli`` at the root of
-the archive.
+command line, in a file called ``.pxarexclude-cli``, at the root of the archive.
 If a file with this name is already present in the source folder during archive
-creation, this file is not included in the archive and the file containing the
-new patterns is added to the archive instead, the original file is not altered.
+creation, this file is not included in the archive, and the file containing the
+new patterns is added to the archive instead. The original file is not altered.
 
 A more convenient and persistent way to exclude files from the archive is by
 placing the glob match patterns in ``.pxarexclude`` files.
 It is possible to create and place these files in any directory of the filesystem
 tree.
-These files must contain one pattern per line, again later patterns win over
-previous ones.
+These files must contain one pattern per line, and later patterns override
+earlier ones.
 The patterns control file exclusions of files present within the given directory
 or further below it in the tree.
 The behavior is the same as described in :ref:`client_creating_backups`.
@@ -89,7 +87,7 @@ with the following command:
 
     # pxar extract archive.pxar /path/to/target
 
-If no target is provided, the content of the archive is extracted to the current
+If no target is provided, the contents of the archive is extracted to the current
 working directory.
 
 In order to restore only parts of an archive, single files, and/or folders,
@@ -116,13 +114,13 @@ run the following command:
     # pxar list archive.pxar
 
 This displays the full path of each file or directory with respect to the
-archives root.
+archive's root.
 
 Mounting an Archive
 ^^^^^^^^^^^^^^^^^^^
 
 ``pxar`` allows you to mount and inspect the contents of an archive via _`FUSE`.
-In order to mount an archive named ``archive.pxar`` to the mountpoint ``/mnt``,
+In order to mount an archive named ``archive.pxar`` to the mount point ``/mnt``,
 run the command:
 
 .. code-block:: console
@@ -130,7 +128,7 @@ run the command:
     # pxar mount archive.pxar /mnt
 
 Once the archive is mounted, you can access its content under the given
-mountpoint.
+mount point.
 
 .. code-block:: console
 
diff --git a/docs/sysadmin.rst b/docs/sysadmin.rst
index 51601f2a..626b28fe 100644
--- a/docs/sysadmin.rst
+++ b/docs/sysadmin.rst
@@ -4,8 +4,8 @@ Host System Administration
 ==========================
 
 `Proxmox Backup`_ is based on the famous Debian_ Linux
-distribution. That means that you have access to the whole world of
-Debian packages, and the base system is well documented. The `Debian
+distribution. This means that you have access to the entire range of
+Debian packages, and that the base system is well documented. The `Debian
 Administrator's Handbook`_ is available online, and provides a
 comprehensive introduction to the Debian operating system.
 
@@ -17,11 +17,11 @@ updates to some Debian packages when necessary.
 
 We also deliver a specially optimized Linux kernel, where we enable
 all required virtualization and container features. That kernel
-includes drivers for ZFS_, and several hardware drivers. For example,
+includes drivers for ZFS_, as well as several hardware drivers. For example,
 we ship Intel network card drivers to support their newest hardware.
 
 The following sections will concentrate on backup related topics. They
-either explain things which are different on `Proxmox Backup`_, or
+will explain things which are different on `Proxmox Backup`_, or
 tasks which are commonly used on `Proxmox Backup`_. For other topics,
 please refer to the standard Debian documentation.
 
diff --git a/docs/technical-overview.rst b/docs/technical-overview.rst
index 4223b2c5..59a59c11 100644
--- a/docs/technical-overview.rst
+++ b/docs/technical-overview.rst
@@ -8,7 +8,7 @@ Datastores
 
 A Datastore is the logical place where :ref:`Backup Snapshots
 <term_backup_snapshot>` and their chunks are stored. Snapshots consist of a
-manifest, blobs, dynamic- and fixed-indexes (see :ref:`terms`), and are
+manifest, blobs, and dynamic- and fixed-indexes (see :ref:`terms`), and are
 stored in the following directory structure:
 
  <datastore-root>/<type>/<id>/<time>/
@@ -32,8 +32,8 @@ The chunks of a datastore are found in
 
  <datastore-root>/.chunks/
 
-This chunk directory is further subdivided by the first four byte of the chunks
-checksum, so the chunk with the checksum
+This chunk directory is further subdivided by the first four bytes of the
+chunk's checksum, so a chunk with the checksum
 
  a342e8151cbf439ce65f3df696b54c67a114982cc0aa751f2852c2f7acc19a8b
 
@@ -47,7 +47,7 @@ per directory can be bad for file system performance.
 These chunk directories ('0000'-'ffff') will be preallocated when a datastore
 is created.
 
-Fixed-sized Chunks
+Fixed-Sized Chunks
 ^^^^^^^^^^^^^^^^^^
 
 For block based backups (like VMs), fixed-sized chunks are used. The content
@@ -58,10 +58,10 @@ often tries to allocate files in contiguous pieces, so new files get new
 blocks, and changing existing files changes only their own blocks.
 
 As an optimization, VMs in `Proxmox VE`_ can make use of 'dirty bitmaps', which
-can track the changed blocks of an image. Since these bitmap are also a
+can track the changed blocks of an image. Since these bitmaps are also a
 representation of the image split into chunks, there is a direct relation
-between dirty blocks of the image and chunks which need to get uploaded, so
-only modified chunks of the disk have to be uploaded for a backup.
+between the dirty blocks of the image and chunks which need to be uploaded.
+Thus, only modified chunks of the disk need to be uploaded to a backup.
 
 Since the image is always split into chunks of the same size, unchanged blocks
 will result in identical checksums for those chunks, so such chunks do not need
@@ -71,24 +71,24 @@ changed blocks.
 For consistency, `Proxmox VE`_ uses a QEMU internal snapshot mechanism, that
 does not rely on storage snapshots either.
 
-Dynamically sized Chunks
+Dynamically Sized Chunks
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
-If one does not want to backup block-based systems but rather file-based
-systems, using fixed-sized chunks is not a good idea, since every time a file
-would change in size, the remaining data gets shifted around and this would
-result in many chunks changing, reducing the amount of deduplication.
+When working with file-based systems rather than block-based systems,
+using fixed-sized chunks is not a good idea, since every time a file
+would change in size, the remaining data would be shifted around,
+resulting in many chunks changing and the amount of deduplication being reduced.
 
 To improve this, `Proxmox Backup`_ Server uses dynamically sized chunks
 instead. Instead of splitting an image into fixed sizes, it first generates a
 consistent file archive (:ref:`pxar <pxar-format>`) and uses a rolling hash
 over this on-the-fly generated archive to calculate chunk boundaries.
 
-We use a variant of Buzhash which is a cyclic polynomial algorithm.  It works
+We use a variant of Buzhash which is a cyclic polynomial algorithm. It works
 by continuously calculating a checksum while iterating over the data, and on
-certain conditions it triggers a hash boundary.
+certain conditions, it triggers a hash boundary.
 
-Assuming that most files of the system that is to be backed up have not
+Assuming that most files on the system that is to be backed up have not
 changed, eventually the algorithm triggers the boundary on the same data as a
 previous backup, resulting in chunks that can be reused.
 
@@ -100,8 +100,8 @@ can be encrypted, and they are handled in a slightly different manner than
 normal chunks.
 
 The hashes of encrypted chunks are calculated not with the actual (encrypted)
-chunk content, but with the plain-text content concatenated with the encryption
-key. This way, two chunks of the same data encrypted with different keys
+chunk content, but with the plain-text content, concatenated with the encryption
+key. This way, two chunks with the same data but encrypted with different keys
 generate two different checksums and no collisions occur for multiple
 encryption keys.
 
@@ -112,14 +112,14 @@ the previous backup, do not need to be encrypted and uploaded.
 Caveats and Limitations
 -----------------------
 
-Notes on hash collisions
+Notes on Hash Collisions
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
 Every hashing algorithm has a chance to produce collisions, meaning two (or
 more) inputs generate the same checksum. For SHA-256, this chance is
-negligible.  To calculate such a collision, one can use the ideas of the
-'birthday problem' from probability theory. For big numbers, this is actually
-infeasible to calculate with regular computers, but there is a good
+negligible. To calculate the chances of such a collision, one can use the ideas
+of the 'birthday problem' from probability theory. For big numbers, this is
+actually unfeasible to calculate with regular computers, but there is a good
 approximation:
 
 .. math::
@@ -127,7 +127,7 @@ approximation:
  p(n, d) = 1 - e^{-n^2/(2d)}
 
 Where `n` is the number of tries, and `d` is the number of possibilities.
-For a concrete example lets assume a large datastore of 1 PiB, and an average
+For a concrete example, lets assume a large datastore of 1 PiB and an average
 chunk size of 4 MiB. That means :math:`n = 268435456` tries, and :math:`d =
 2^{256}` possibilities. Inserting those values in the formula from earlier you
 will see that the probability of a collision in that scenario is:
@@ -136,94 +136,96 @@ will see that the probability of a collision in that scenario is:
 
  3.1115 * 10^{-61}
 
-For context, in a lottery game of guessing 6 out of 45, the chance to correctly
-guess all 6 numbers is only :math:`1.2277 * 10^{-7}`, that means the chance of
-a collision is about the same as winning 13 such lotto games *in a row*.
+For context, in a lottery game of guessing 6 numbers out of 45, the chance to
+correctly guess all 6 numbers is only :math:`1.2277 * 10^{-7}`. This means the
+chance of a collision is about the same as winning 13 such lottery games *in a
+row*.
 
 In conclusion, it is extremely unlikely that such a collision would occur by
 accident in a normal datastore.
 
 Additionally, SHA-256 is prone to length extension attacks, but since there is
-an upper limit for how big the chunk are, this is not a problem, since a
+an upper limit for how big the chunks are, this is not a problem, because a
 potential attacker cannot arbitrarily add content to the data beyond that
 limit.
 
-File-based Backup
+File-Based Backup
 ^^^^^^^^^^^^^^^^^
 
 Since dynamically sized chunks (for file-based backups) are created on a custom
 archive format (pxar) and not over the files directly, there is no relation
-between files and the chunks. This means  that the Proxmox Backup client has to
+between the files and chunks. This means that the Proxmox Backup Client has to
 read all files again for every backup, otherwise it would not be possible to
-generate a consistent independent pxar archive where the original chunks can be
-reused. Note that there will be still only new or change chunks be uploaded.
+generate a consistent, independent pxar archive where the original chunks can be
+reused. Note that in spite of this, only new or changed chunks will be uploaded.
 
-Verification of encrypted chunks
+Verification of Encrypted Chunks
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 For encrypted chunks, only the checksum of the original (plaintext) data is
-available, making it impossible for the server (without the encryption key), to
+available, making it impossible for the server (without the encryption key) to
 verify its content against it. Instead only the CRC-32 checksum gets checked.
 
 Troubleshooting
 ---------------
 
-Index files(.fidx, .didx) contain information about how to rebuild a file, more
-precisely, they contain an ordered list of references to the chunks the original
-file was split up in. If there is something wrong with a snapshot it might be
-useful to find out which chunks are referenced in this specific snapshot, and
-check wheather all of them are present and intact. The command for getting the
-list of referenced chunks could look something like this:
+Index files(*.fidx*, *.didx*) contain information about how to rebuild a file.
+More precisely, they contain an ordered list of references to the chunks that
+the original file was split into. If there is something wrong with a snapshot,
+it might be useful to find out which chunks are referenced in it, and check
+whether they are present and intact. The ``proxmox-backup-debug`` command line
+tool can be used to inspect such files and recover their contents. For example,
+to get a list of the referenced chunks of a *.fidx* index:
 
 .. code-block:: console
 
     # proxmox-backup-debug inspect file drive-scsi0.img.fidx
 
-The same command can be used to look at .blob file, without ``--decode`` just
-the size and the encryption type, if any, is printed. If ``--decode`` is set the
-blob file is decoded into the specified file('-' will decode it directly into
-stdout).
+The same command can be used to inspect *.blob* files. Without the ``--decode``
+parameter, just the size and the encryption type, if any, are printed. If
+``--decode`` is set, the blob file is decoded into the specified file ('-' will
+decode it directly to stdout).
+
+The following example would print the decoded contents of
+`qemu-server.conf.blob`. If the file you're trying to inspect is encrypted, a
+path to the key file must be provided using ``--keyfile``.
 
 .. code-block:: console
 
     # proxmox-backup-debug inspect file qemu-server.conf.blob --decode -
 
-would print the decoded contents of `qemu-server.conf.blob`. If the file you're
-trying to inspect is encrypted, a path to the keyfile has to be provided using
-``--keyfile``.
-
-Checking in which index files a specific chunk file is referenced can be done
+You can also check in which index files a specific chunk file is referenced
 with:
 
 .. code-block:: console
 
     # proxmox-backup-debug inspect chunk b531d3ffc9bd7c65748a61198c060678326a431db7eded874c327b7986e595e0 --reference-filter /path/in/a/datastore/directory
 
-Here ``--reference-filter`` specifies where index files should be searched, this
+Here ``--reference-filter`` specifies where index files should be searched. This
 can be an arbitrary path. If, for some reason, the filename of the chunk was
-changed you can explicitly specify the digest using ``--digest``, by default the
-chunk filename is used as the digest to look for. Specifying no
-``--reference-filter`` will just print the CRC and encryption status of the
-chunk. You can also decode chunks, to do so ``--decode`` has to be set. If the
-chunk is encrypted a ``--keyfile`` has to be provided for decoding.
+changed, you can explicitly specify the digest using ``--digest``. By default, the
+chunk filename is used as the digest to look for. If no ``--reference-filter``
+is specified, it will only print the CRC and encryption status of the chunk. You
+can also decode chunks, by setting the ``--decode`` flag. If the chunk is
+encrypted, a ``--keyfile`` must be provided, in order to decode it.
 
-Restore without a running PBS
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+Restore without a Running Proxmox Backup Server
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-It is possible to restore spefiic files of snapshots without a running PBS using
-the `recover` sub-command, provided you have access to the intact index and
-chunk files. Note that you also need the corresponding key file if the backup
-was encrypted.
+It's possible to restore specific files from a snapshot, without a running
+Proxmox Backup Server instance, using the ``recover`` subcommand, provided you
+have access to the intact index and chunk files. Note that you also need the
+corresponding key file if the backup was encrypted.
 
 .. code-block:: console
 
     # proxmox-backup-debug recover index drive-scsi0.img.fidx /path/to/.chunks
 
-In above example the `/path/to/.chunks` argument is the path to the directory
-that contains contains the chunks, and `drive-scsi0.img.fidx` is the index-file
-of the file you'd lile to restore. Both paths can be absolute or relative. With
-``--skip-crc`` it is possible to disable the crc checks of the chunks, this will
-speed up the process slightly and allows for trying to restore (partially)
+In the above example, the `/path/to/.chunks` argument is the path to the
+directory that contains the chunks, and `drive-scsi0.img.fidx` is the index file
+of the file you'd like to restore. Both paths can be absolute or relative. With
+``--skip-crc``, it's possible to disable the CRC checks of the chunks. This
+will speed up the process slightly and allow for trying to restore (partially)
 corrupt chunks. It's recommended to always try without the skip-CRC option
 first.
 
-- 
2.30.2





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