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Easy Zope backup/restore recipe for buildout

Contents

Introduction

This recipe is mostly a wrapper around the bin/repozo script in your Zope buildout. It requires that this script is already made available. If this is not the case, you will get an error like this when you run one of the scripts: bin/repozo: No such file or directory. This should be there when you are using plone.recipe.zeoserver. If this is not the case, the easiest way of getting a bin/repozo script is to add a new section in your buildout.cfg (do not forget to add it in the parts directive):

[repozo]
recipe = zc.recipe.egg
eggs = ZODB
# or this for an older version:
# eggs = ZODB3
scripts = repozo
dependent-scripts = true

bin/repozo is a Zope script to make backups of your Data.fs. Looking up the settings can be a chore. And you have to pick a directory where to put the backups. This recipe provides sensible defaults for your common backup tasks. Making backups a piece of cake is important!

  • bin/backup makes an incremental backup.
  • bin/restore restores the latest backup created by the backup script.
  • bin/snapshotbackup makes a full snapshot backup, separate from the regular backups. Handy right before a big change in the site.
  • bin/snapshotrestore restores the latest full snapshot backup.
  • bin/zipbackup makes a zip backup. This zips the Data.fs and the blobstorage, handy for copying production data to your local machine, especially the blobstorage with its many files. Actually, zipping the Data.fs is standard, and we do not zip the blobstorage, because most files in there are already compressed. But we do combine the blobs in one tar archive. Note: the Data.fs and blobstorage (or other storages) are not combined in one file; you need to download multiple files. Enable this script by using the enable_zipbackup option.
  • bin/ziprestore restores the latest zipbackup.

Compatibility

The recipe is tested with Python 2.7, 3.6, 3.7, 3.8, 3.9. In Plone terms it works fine on Plone 4, 5 and 6.

Note that the integration with plone.recipe.zope2instance is not tested on Python 3. It would pulls in too many dependencies, like Zope and ZODB.

Development

Example usage

The simplest way to use this recipe is to add a part in buildout.cfg like this:

[buildout]
parts = backup

[backup]
recipe = collective.recipe.backup

You can set lots of extra options, but the recipe authors like to think they have created sane defaults, so this single line stating the recipe name should be enough in most cases.

Running the buildout adds the backup, snapshotbackup, zipbackup, restore, snapshotrestore and ziprestore scripts to the bin/ directory of the buildout. Some are not added by default, others can be switched off.

Backed up data

Which data does this recipe backup?

  • The Zope Object DataBase (ZODB) filestorage, by default located at var/filestorage/Data.fs.
  • The blobstorage (since version 2.0) if your buildout uses it, by default located at var/blobstorage.

Data that is not backed up

Which data does this recipe not backup? Everything else of course, but specifically:

  • Data stored in RelStorage will not be backed up. (You could still use this recipe to back up the filesystem blobstorage, possibly with the only_blobs option.)
  • Other data stored in SQL, perhaps via SQLAlchemy, will not be backed up.
  • It does not create a backup of your entire buildout directory.

Is your backup backed up?

Note that the backups are by default created in the var directory of the buildout, so if you accidentally remove the entire buildout, you also lose your backups. It should be standard practice to use the location option to specify a backup location in for example the home directory of the user. You should also arrange to copy that backup to a different machine/country/continent/planet.

Backup

Calling bin/backup results in a normal incremental repozo backup that creates a backup of the Data.fs in var/backups. When you have a blob storage it is by default backed up to var/blobstoragebackups.

Snapshots

A quick backup just before updating the production server is a good idea. But you may not want to interfere with the regular backup regime. For that, the bin/snapshotbackup is great. It places a full backup in, by default, var/snapshotbackups.

Zipbackups

For quickly grabbing the current state of a production database so you can download it to your development laptop, you want a full and zipped backup. The zipped part is important for the blobstorage, because you do not want to use scp to recursively copy over all those blob files: downloading one tarball is faster.

You can use the bin/zipbackup script for this. This script overrides a few settings, ignoring whatever is set in the buildout config section:

  • archive_blob is turned on.
  • keep is set to 1 to avoid keeping lots of needless backups.
  • keep_blob_days is ignored because it is a full backup.

The script places a full backup in, by default, var/zipbackups and it puts a tarball of the blobstorage in var/blobstoragezips.

This script is not created by default. You can enable it by setting the enable_zipbackup option to true. Also, if backup_blobs is false, the scripts are useless, so we do not create them, even when you have enabled them explicitly.

Restore

Calling bin/restore restores the very latest normal incremental repozo backup and restores the blobstorage if you have that.

You can restore the very latest snapshotbackup with bin/snapshotrestore.

You can restore the zipbackup with bin/ziprestore.

You can also restore the backup as of a certain date. Just pass a date argument. According to repozo: specify UTC (not local) time. The format is yyyy-mm-dd[-hh[-mm[-ss]]]. So as a simple example, restore to 25 december 1972:

bin/restore 1972-12-25

or to that same date, at 2,03 seconds past 1:

bin/restore 1972-12-25-01-02-03

Since version 2.3 this also works for restoring blobs. We restore the directory from the first backup at or before the specified date. (Note that before version 4.0 we restored the directory from the first backup after the specified date, which should be fine as long as you did not do a database pack in between.)

Since version 2.0, the restore scripts ask for confirmation before starting the restore, as this is a potentially dangerous command. ("Oops, I have restored the live site but I meant to restore the test site.") You need to explicitly type 'yes':

This will replace the filestorage (Data.fs).
This will replace the blobstorage.
Are you sure? (yes/No)?

Note that for large filestorages and blobstorages it may take long to restore. You should do a test restore and check how long it takes. Seconds? Minutes? Hours? Is that time acceptable or should you take other measures?

Names of created scripts

A backup part will normally be called [backup], leading to a bin/backup and bin/snapshotbackup. Should you name your part something else, the script names will also be different, as will the created var/ directories (since version 1.2):

[buildout]
parts = plonebackup

[plonebackup]
recipe = collective.recipe.backup
enable_zipbackup = true

That buildout snippet will create these scripts:

bin/plonebackup
bin/plonebackup-full
bin/plonebackup-zip
bin/plonebackup-snapshot
bin/plonebackup-restore
bin/plonebackup-ziprestore
bin/plonebackup-snapshotrestore

Supported options

The recipe supports the following options, none of which are needed by default. The most common ones to change are location and blobbackuplocation, as those allow you to place your backups in some system-wide directory like /var/zopebackups/instancename/ and /var/zopebackups/instancename-blobs/.

archive_blob
Use tar archiving functionality. false by default. Set it to true and backup/restore will be done with tar command. Note that tar command must be available on machine if this option is set to true. This option also works with snapshot backup/restore commands. As this counts as a full backup keep_blob_days is ignored. See the compress_blob option if you want to compress the archive.
alternative_restore_source
You can restore from an alternative source. Use case: first make a backup of your production site, then go to the testing or staging server and restore the production data there. See Alternative restore source
alternative_restore_sources
Backwards compatibility spelling for alternative_restore_source. This will no longer work in version 7.
backup_blobs
Backup the blob storage. Default is True on Python 2.6 (Plone 4) and higher, and False otherwise. This requires the blob_storage location to be set. If no blob_storage location has been set and we cannot find one by looking in the other buildout parts, we quit with an error (since version 2.22). If backup_blobs is false, enable_zipbackup cannot be true, because the zipbackup script is not useful then.
blob_storage
Location of the directory where the blobs (binary large objects) are stored. This is used in Plone 4 and higher, or on Plone 3 if you use plone.app.blob. This option is ignored if backup_blobs is false. The location is not set by default. When there is a part using plone.recipe.zeoserver, plone.recipe.zope2instance or plone.recipe.zope2zeoserver, we check if that has a blob-storage option and use that as default. Note that we pick the first one that has this option and we do not care about shared-blob settings, so there are probably corner cases where we do not make the best decision here. Use this option to override it in that case.
blob-storage
Alternative spelling for the preferred blob_storage, as plone.recipe.zope2instance spells it as blob-storage and we are using underscores in all the other options. Pick one.
blob_timestamps
New in version 4.0. Default is true (this was false before version 4.2). If false, we create blobstorage.0. The next time, we rotate this to blobstorage.1 and create a new blobstorage.0. With blob_timestamps = true, we create stable directories that we do not rotate. They get a timestamp, the same timestamp that the ZODB filestorage backup gets. For example: blobstorage.1972-12-25-01-02-03. Or with archive_blob = true: blobstorage.1972-12-25-01-02-03.tar. Because the filename is unpredictable, since version 4.1 we create a latest symlink to the most recent backup. Blob timestamps are not used with zipbackup, because this only keeps 1 backup, which means there is no confusion about which filestorage backup it belongs to.
blobbackuplocation
Directory where the blob storage will be backed up to. Defaults to var/blobstoragebackups inside the buildout directory.
blobsnapshotlocation
Directory where the blob storage snapshots will be created. Defaults to var/blobstoragesnapshots inside the buildout directory.
blobziplocation
Directory where the blob storage zipbackups will be created. Defaults to var/blobstoragezips inside the buildout directory.
compress_blob
New in version 4.0. Default is false. This is only used when the archive_blob option is true. When switched on, it will compress the archive, resulting in a .tar.gz instead of a tar file. When restoring, we always look for both compressed and normal archives. We used to always compress them, but in most cases it hardly decreases the size and it takes a long time anyway. I have seen archiving take 15 seconds, and compressing take an additional 45 seconds. The result was an archive of 5.0 GB instead of 5.1 GB.
datafs
In case the Data.fs isn't in the default var/filestorage/Data.fs location, this option can overwrite it.
debug
In rare cases when you want to know exactly what's going on, set debug to true to get debug level logging of the recipe itself. repozo is also run with --verbose if this option is enabled.
enable_snapshotrestore
Having a snapshotrestore script is very useful in development environments, but can be harmful in a production buildout. The script restores the latest snapshot directly to your filestorage and it used to do this without asking any questions whatsoever (this has been changed to require an explicit yes as answer). If you don't want a snapshotrestore script, set this option to false.
enable_zipbackup
Create zipbackup and ziprestore scripts. Default: false. If backup_blobs is not on, these scripts are always disabled, because they are not useful then.
full
By default, incremental backups are made. If this option is set to true, bin/backup will always make a full backup.
incremental_blobs
New in version 4.0. Default is false. When switched on, it will use the --listed-incremental option of tar. Note: this only works with the GNU version of tar. On Mac you may need to install this with brew install gnu-tar and change your PATH according to the instructions. It will create a metadata or snapshot file so that a second call to the backup script will create a second tarball with only the differences. For some reason, all directories always end up in the second tarball, even when there are no changes; this may depend on the used file system. This option is ignored when the archive_blob option is false. This option requires the blob_timestamps option to be true, because it needs the tarball names to be stable, instead of getting rotated. If you have explicitly set blob_timestamps to false, buildout will exit with an error. Note that the latest symlink to the most recent backup is not created with incremental_blobs true. For large blobstorages it may take long to restore, so do test it out. But that is wise in all cases. Essentially, this feature seems to trade off storage space reduction with restore time.
keep
Number of full backups to keep. Defaults to 2, which means that the current and the previous full backup are kept. Older backups are removed, including their incremental backups. Set it to 0 to keep all backups.
keep_blob_days
Number of days of blob backups to keep. Defaults to 14, so two weeks. This is only used for partial (full=False) backups, so this is what gets used normally when you do a bin/backup. This option has been added in 2.2. For full backups (snapshots) we just use the keep option. Recommended is to keep these values in sync with how often you do a zeopack on the Data.fs, according to the formula keep * days_between_zeopacks = keep_blob_days. The default matches one zeopack per seven days (2*7=14). Since version 4.0, this option is ignored unless only_blobs is true. Instead, we remove the blob backups that have no matching filestorage backup.
location
Location where backups are stored. Defaults to var/backups inside the buildout directory.
locationprefix
Location of the folder where all other backup and snapshot folders will be created. Defaults to var/. Note that this does not influence where we look for a source filestorage or blobstorage.
only_blobs
Only backup the blobstorage, not the Data.fs filestorage. False by default. May be a useful option if for example you want to create one bin/filestoragebackup script and one bin/blobstoragebackup script, using only_blobs in one and backup_blobs in the other.
post_command
Command to execute after the backup has finished. One use case would be to unmount the remote file system that you mounted earlier using the pre_command. See that pre_command above for more info.
pre_command
Command to execute before starting the backup. One use case would be to mount a remote file system using NFS or sshfs and put the backup there. Any output will be printed. If you do not like that, you can always redirect output somewhere else (mycommand > /dev/null on Unix). Refer to your local Unix guru for more information. If the command fails, the backup script quits with an error. You can specify multiple commands.
quick

Call repozo with the --quick option. This option was introduced to collective.recipe.backup in version 2.19, with default value true. Due to all the checksums that the repozo default non-quick behavior does, an amount of data is read that is three to four times as much as is in the actual filestorage. With the quick option it could easily be just a few kilobytes. Theoretically the quick option is less safe, but it looks like it can only go wrong when someone edits the .dat file in the repository or removes a .deltafs file.

The quick option only influences the created bin/backup script. It has no effect on the snapshot or restore scripts.

The repozo help says about this option: "Verify via md5 checksum only the last incremental written. This significantly reduces the disk i/o at the (theoretical) cost of inconsistency. This is a probabilistic way of determining whether a full backup is necessary."

rsync_options
Add extra options to the default rsync -a command. Default is no extra parameters. This can be useful for example when you want to restore a backup from a symlinked directory, in which case rsync_options = --no-l -k does the trick.
rsync_hard_links_on_first_copy
When using rsync, the blob files for the first backup are copied and then subsequent backups make use of hard links from this initial copy, to save time and disk space. Enable this option to also use hard links for the initial copy to further reduce disk usage. This is safe for ZODB blobs, since they are not modified in place. The blob_storage and the backup folder blobbackuplocation have to be in the same partition for hard links to be possible.
snapshotlocation
Location where snapshot backups of the filestorage are stored. Defaults to var/snapshotbackups inside the buildout directory.
use_rsync
Use rsync with hard links for backing up the blobs. Default is true. rsync is probably not available on all machines though, and I guess hard links will not work on Windows. When you set this to false, we fall back to a simple copy (shutil.copytree from Python in fact).
ziplocation
Location where zip backups of the filestorage are stored. Defaults to var/zipbackups inside the buildout directory.

An example buildout snippet using various options, would look like this:

[backup]
recipe = collective.recipe.backup
location = ${buildout:directory}/myproject
keep = 2
datafs = subfolder/myproject.fs
full = true
debug = true
snapshotlocation = snap/my
enable_snapshotrestore = true
pre_command = echo 'Can I have a backup?'
post_command =
    echo 'Thanks a lot for the backup.'
    echo 'We are done.'

Paths in directories or files can use relative (../) paths, and ~ (home dir) and $BACKUP-style environment variables are expanded.

Cron job integration

bin/backup is of course ideal to put in your cronjob instead of a whole bin/repozo .... line. But you don't want the "INFO" level logging that you get, as you'll get that in your mailbox. In your cronjob, just add -q or --quiet, and bin/backup will shut up unless there's a problem. This option ignores the debug variable, if set to true in buildout.

Speaking of cron jobs? Take a look at zc.recipe.usercrontab if you want to handle cronjobs from within your buildout. For example:

[backupcronjob]
recipe = z3c.recipe.usercrontab
times = 0 12 * * *
command = ${buildout:directory}/bin/backup

Blob storage

Added in version 2.0.

We can backup the blob storage. Plone 4 uses a blob storage to store files (Binary Large OBjects) on the file system. In Plone 3 this is optional. When this is used, it should be backed up of course. You must specify the source blob_storage directory where Plone (or Zope) stores its blobs. As indicated earlier, when we do not set it specifically, we try to get the location from other parts, for example the plone.recipe.zope2instance recipe:

[buildout]
parts = instance backup

[instance]
recipe = plone.recipe.zope2instance
user = admin:admin
blob-storage = ${buildout:directory}/var/somewhere

[backup]
recipe = collective.recipe.backup

If needed, we can tell buildout that we only want to backup blobs or specifically do not want to backup the blobs. Specifying this using the backup_blobs and only_blobs options might be useful in case you want to separate this into several scripts:

[buildout]
newest = false
parts = filebackup blobbackup

[filebackup]
recipe = collective.recipe.backup
backup_blobs = false

[blobbackup]
recipe = collective.recipe.backup
blob_storage = ${buildout:directory}/var/blobstorage
only_blobs = true

With this setup bin/filebackup now only backs up the filestorage and bin/blobbackup only backs up the blobstorage.

New in version 4.0: you may want to specify blob_timestamps = true. Then we create stable directories that we do not rotate. For example: blobstorage.1972-12-25-01-02-03 instead of blobstorage.0.

rsync

By default we use rsync to create backups. We create hard links with this tool, to save disk space and still have incremental backups. This probably requires a unixy (Linux, Mac OS X) operating system. It is based on this article by Mike Rubel: http://www.mikerubel.org/computers/rsync_snapshots/

We have not tried this on Windows. Reports are welcome, but best is probably to set the use_rsync = false option in the backup part. Then we simply copy the blobstorage directory.

Alternative restore source

Added in version 2.17. Changed in version 5: only one source is supported.

You can restore from an alternative source. Use case: first make a backup of your production site, then go to the testing or staging server and restore the production data there.

In the alternative_restore_source option you can define different filestorage and blobstorage backup source directories using this syntax:

alternative_restore_source =
    storagename datafs1_backup [blobdir1_backup]

The storagename must be Data (or 1) for the standard Data.fs and optionally its blobstorage.

The result is a bin/altrestore script.

This will work for a standard buildout with a single filestorage and blobstorage:

[backup]
recipe = collective.recipe.backup
alternative_restore_source =
    Data /path/to/production/var/backups /path/to/production/var/blobstoragebackups

The above configuration uses repozo to restore the Data.fs from the /path/to/production/var/backups repository to the standard var/filestorage/Data.fs location. It copies the most recent blobstorage backup from /path/to/production/var/blobstoragebackups/ to the standard var/blobstorage location.

Calling the script with a specific date is supported just like the normal restore script:

bin/altrestore 2000-12-31-23-59

The recipe will fail if the alternative source does not match the standard filestorage and blobstorage. For example, you get an error when the alternative_restore_source is missing the Data key, when it has an extra key, when a key has no paths, when a key has an extra or missing blobstorage.

During install of the recipe, so during the bin/buildout run, it does not check if the sources exist: you might have the production backups on a different server and need to setup a remote shared directory, or you copy the data over manually.

Note that the script takes the archive_blob and use_rsync options into account. So if the alternative restore source contains a blob backup that was made with archive_blob = true, you need an altrestore script that also uses this setting.