Freezer is a Python tool that helps you to automate the data backup and restore process.
The following features are available:
- Backup your filesystem using snapshot to swift
- Strong encryption supported: AES-256-CFB
- Backup your file system tree directly (without volume snapshot)
- Backup your journaled MongoDB directory tree using lvm snap to swift
- Backup MySQL DB with lvm snapshot
- Restore your data automatically from Swift to your file system
- Low storage consumption as the backup are uploaded as a stream
- Flexible Incremental backup policy
- Data is archived in GNU Tar format
- Data compression with gzip
- Remove old backup automatically according the provided parameters
- OpenStack Swift Account (Auth V2 used)
- python
- GNU Tar >= 1.26
- gzip
- OpenSSL
- python-swiftclient
- python-keystoneclient
- pymongo
- python-mysqldb
- libmysqlclient-dev
- At least 128 MB of memory reserved for Freezer
Swift client and Keystone client:
$ sudo apt-get install -y python-swiftclient python-keystoneclient
MongoDB backup:
$ sudo apt-get install -y python-pymongo
MySQL backup:
$ sudo apt-get install -y python-mysqldb libmysqlclient-dev
Freezer installation from Python package repo:
$ sudo pip install freezer
OR:
$ sudo easy_install freezer
The basic Swift account configuration is needed to use freezer. Make sure python-swiftclient is installed.
Also the following ENV var are needed you can put them in ~/.bashrc:
export OS_REGION_NAME=region-a.geo-1 export OS_TENANT_ID=<account tenant> export OS_PASSWORD=<account password> export OS_AUTH_URL=https://region-a.geo-1.identity.hpcloudsvc.com:35357/v2.0 export OS_USERNAME=automationbackup export OS_TENANT_NAME=automationbackup $ source ~/.bashrc
Let's say you have a container called freezer_foobar-container, by executing "swift list" you should see something like:
$ swift list freezer_foobar-container-2 $
These are just use case example using Swift in the HP Cloud.
Is strongly advised to use execute a backup using LVM snapshot, so freezer will execute a backup on point-in-time data. This avoid risks of data inconsistencies and corruption.
Freezer will automatically add the prefix "freezer" to the container name, where it is provided by the user and doesn't already start with this prefix. If no container name is provided, the default is freezer_backups.
The most simple backup execution is a direct file system backup:
$ sudo freezerc --file-to-backup /data/dir/to/backup --container freezer_new-data-backup --backup-name my-backup-name
By default --mode fs is set. The command would generate a compressed tar gzip file of the directory /data/dir/to/backup. The generated file will be segmented in stream and uploaded in the swift container called freezer_new-data-backup, with backup name my-backup-name
Now check if your backup is executing correctly looking at /var/log/freezer.log
Execute a MongoDB backup using lvm snapshot:
We need to check before on which volume group and logical volume our mongo data is. These information can be obtained as per following:
$ mount [...]
Once we know the volume where our Mongo data is mounted on, we can get the volume group and logical volume info:
$ sudo vgdisplay [...] $ sudo lvdisplay [...]
We assume our mongo volume is "/dev/mongo/mongolv" and the volume group is "mongo":
$ sudo freezerc --lvm-srcvol /dev/mongo/mongolv --lvm-dirmount /var/lib/snapshot-backup --lvm-volgroup mongo --file-to-backup /var/lib/snapshot-backup/mongod_ops2 --container freezer_mongodb-backup-prod --exclude "*.lock" --mode mongo --backup-name mongod-ops2
Now freezerc create a lvm snapshot of the volume /dev/mongo/mongolv. If no options are provided, default snapshot name is freezer_backup_snap. The snap vol will be mounted automatically on /var/lib/snapshot-backup and the backup meta and segments will be upload in the container mongodb-backup-prod with the name mongod-ops2.
Execute a file system backup using lvm snapshot:
$ sudo freezerc --lvm-srcvol /dev/jenkins/jenkins-home --lvm-dirmount /var/snapshot-backup --lvm-volgroup jenkins --file-to-backup /var/snapshot-backup --container freezer_jenkins-backup-prod --exclude "\*.lock" --mode fs --backup-name jenkins-ops2
MySQL backup require a basic configuration file. The following is an example of the config:
$ sudo cat /root/.freezer/db.conf host = your.mysql.host.ip user = backup password = userpassword
Every listed option is mandatory. There's no need to stop the mysql service before the backup execution.
Execute a MySQL backup using lvm snapshot:
$ sudo freezerc --lvm-srcvol /dev/mysqlvg/mysqlvol --lvm-dirmount /var/snapshot-backup --lvm-volgroup mysqlvg --file-to-backup /var/snapshot-backup --mysql-conf /root/.freezer/freezer-mysql.conf--container freezer_mysql-backup-prod --mode mysql --backup-name mysql-ops002
All the freezerc activities are logged into /var/log/freezer.log.
As a general rule, when you execute a restore, the application that write or read data should be stopped.
There are 3 main options that need to be set for data restore
File System Restore:
Execute a file system restore of the backup name adminui.git:
$ sudo freezerc --action restore --container freezer_foobar-container-2 --backup-name adminui.git --restore-from-host git-HP-DL380-host-001 --restore-abs-path /home/git/repositories/adminui.git/ --restore-from-date "2014-05-23T23:23:23"
MySQL restore:
Execute a MySQL restore of the backup name holly-mysql. Let's stop mysql service first:
$ sudo service mysql stop
Execute Restore:
$ sudo freezerc --action restore --container freezer_foobar-container-2 --backup-name mysq-prod --restore-from-host db-HP-DL380-host-001 --restore-abs-path /var/lib/mysql --restore-from-date "2014-05-23T23:23:23"
And finally restart mysql:
$ sudo service mysql start
Execute a MongoDB restore of the backup name mongobigdata:
$ sudo freezerc --action restore --container freezer_foobar-container-2 --backup-name mongobigdata --restore-from-host db-HP-DL380-host-001 --restore-abs-path /var/lib/mongo --restore-from-date "2014-05-23T23:23:23"
List remote containers:
$ sudo freezerc --action info -L
List remote objects in container:
$ sudo freezerc --action info --container freezer_testcontainer -l
Remove backups older then 1 day:
$ freezerc --action admin --container freezer_dev-test --remove-older-then 1 --backup-name dev-test-01
Freezer architecture is simple. The components are:
- OpenStack Swift (the storage)
- freezer client running on the node you want to execute the backups or restore
Frezeer use GNU Tar under the hood to execute incremental backup and restore. When a key is provided, it uses OpenSSL to encrypt data (AES-256-CFB)
Freezer is designed to reduce at the minimum I/O, CPU and Memory Usage. This is achieved by generating a data stream from tar (for archiving) and gzip (for compressing). Freezer segment the stream in a configurable chunk size (with the option --max-seg-size). The default segment size is 64MB, so it can be safely stored in memory, encrypted if the key is provided, and uploaded to Swift as segment.
Multiple segments are sequentially uploaded using the Swift Manifest. All the segments are uploaded first, and then the Manifest file is uploaded too, so the data segments cannot be accessed directly. This ensue data consistency.
By keeping small segments in memory, I/O usage is reduced. Also as there's no need to store locally the final compressed archive (tar-gziped), no additional or dedicated storage is required for the backup execution. The only additional storage needed is the LVM snapshot size (set by default at 5GB). The lvm snapshot size can be set with the option --lvm-snapsize. It is important to not specify a too small snap size, because in case a quantity of data is being wrote to the source volume and consequently the lvm snapshot is filled up, then the data is corrupted.
If the more memory is available for the backup process, the maximum segment size can be increased, this will speed up the process. Please note, the segments must be smaller then 5GB, is that is the maximum object size in the Swift server.
Au contraire, if a server have small memory availability, the --max-seg-size option can be set to lower values. The unit of this option is in bytes.
The incremental backups is one of the most crucial feature. The following basic logic happens when Freezer execute:
- Freezer start the execution and check if the provided backup name for the current node already exist in Swift
- If the backup exists, the Manifest file is retrieved. This is important as the Manifest file contains the information of the previous Freezer execution.
The following is what the Swift Manifest looks like:
{
'X-Object-Meta-Encrypt-Data': 'Yes',
'X-Object-Meta-Segments-Size-Bytes': '134217728',
'X-Object-Meta-Backup-Created-Timestamp': '1395734461',
'X-Object-Meta-Remove-Backup-Older-Than-Days': '',
'X-Object-Meta-Src-File-To-Backup': '/var/lib/snapshot-backup/mongod_dev-mongo-s1',
'X-Object-Meta-Maximum-Backup-level': '0',
'X-Object-Meta-Always-Backup-Level': '',
'X-Object-Manifest': u'socorro-backup-dev_segments/dev-mongo-s1-r1_mongod_dev-mongo-s1_1395734461_0',
'X-Object-Meta-Providers-List': 'HP',
'X-Object-Meta-Backup-Current-Level': '0',
'X-Object-Meta-Abs-File-Path': '',
'X-Object-Meta-Backup-Name': 'mongod_dev-mongo-s1',
'X-Object-Meta-Tar-Meta-Obj-Name': 'tar_metadata_dev-mongo-s1-r1_mongod_dev-mongo-s1_1395734461_0',
'X-Object-Meta-Hostname': 'dev-mongo-s1-r1',
'X-Object-Meta-Container-Segments': 'socorro-backup-dev_segments'
}
- The most relevant data taken in consideration for incremental are:
- 'X-Object-Meta-Maximum-Backup-level': '7'
Value set by the option: --max-level int
Assuming we are executing the backup daily, let's say managed from the crontab, the first backup will start from Level 0, that is, a full backup. At every daily execution, the current backup level will be incremented by 1. Then current backup level is equal to the maximum backup level, then the backup restart to level 0. That is, every week a full backup will be executed.
- 'X-Object-Meta-Always-Backup-Level': ''
Value set by the option: --always-level int
When current level is equal to 'Always-Backup-Level', every next backup will be executed to the specified level. Let's say --always-level is set to 1, the first backup will be a level 0 (complete backup) and every next execution will backup the data exactly from the where the level 0 ended. The main difference between Always-Backup-Level and Maximum-Backup-level is that the counter level doesn't restart from level 0
- 'X-Object-Manifest': u'socorro-backup-dev/dev-mongo-s1-r1_mongod_dev-mongo-s1_1395734461_0'
Through this meta data, we can identify the exact Manifest name of the provided backup name. The syntax is: container_name/hostname_backup_name_timestamp_initiallevel
- 'X-Object-Meta-Providers-List': 'HP'
This option is NOT implemented yet The idea of Freezer is to support every Cloud provider that provide Object Storage service using OpenStack Swift. The meta data allows you to specify multiple provider and therefore store your data in different Geographic location.
- 'X-Object-Meta-Backup-Current-Level': '0'
Record the current backup level. This is important as the value is incremented by 1 in the next freezer execution.
- 'X-Object-Meta-Backup-Name': 'mongod_dev-mongo-s1'
Value set by the option: -N BACKUP_NAME, --backup-name BACKUP_NAME The option is used to identify the backup. It is a mandatory option and fundamental to execute incremental backup. 'Meta-Backup-Name' and 'Meta-Hostname' are used to uniquely identify the current and next incremental backups
- 'X-Object-Meta-Tar-Meta-Obj-Name': 'tar_metadata_dev-mongo-s1-r1_mongod_dev-mongo-s1_1395734461_0'
Freezer use tar to execute incremental backup. What tar do is to store in a meta data file the inode information of every file archived. Thus, on the next Freezer execution, the tar meta data file is retrieved and download from swift and it is used to generate the next backup level. After the next level backup execution is terminated, the file update tar meta data file will be uploaded and recorded in the Manifest file. The naming convention used for this file is: tar_metadata_backupname_hostname_timestamp_backuplevel
- 'X-Object-Meta-Hostname': 'dev-mongo-s1-r1'
The hostname of the node where the Freezer perform the backup. This meta data is important to identify a backup with a specific node, thus avoid possible confusion and associate backup to the wrong node.
Available options:
$ freezerc
usage: freezerc [-h] [--action {backup,restore,info,admin}] [-F SRC_FILE]
[-N BACKUP_NAME] [-m MODE] [-C CONTAINER] [-L] [-l]
[-o OBJECT] [-d DST_FILE] [--lvm-auto-snap LVM_AUTO_SNAP]
[--lvm-srcvol LVM_SRCVOL] [--lvm-snapname LVM_SNAPNAME]
[--lvm-snapsize LVM_SNAPSIZE] [--lvm-dirmount LVM_DIRMOUNT]
[--lvm-volgroup LVM_VOLGROUP] [--max-level MAX_BACKUP_LEVEL]
[--always-level ALWAYS_BACKUP_LEVEL]
[--restart-always-level RESTART_ALWAYS_BACKUP]
[-R REMOVE_OLDER_THAN] [--no-incremental]
[--hostname HOSTNAME] [--mysql-conf MYSQL_CONF_FILE]
[--log-file LOG_FILE] [--exclude EXCLUDE]
[--dereference-symlink {none,soft,hard,all}] [-U]
[--encrypt-pass-file ENCRYPT_PASS_FILE] [-M MAX_SEG_SIZE]
[--restore-abs-path RESTORE_ABS_PATH]
[--restore-from-host RESTORE_FROM_HOST]
[--restore-from-date RESTORE_FROM_DATE] [--max-priority] [-V]
optional arguments:
-h, --help show this help message and exit
--action {backup,restore,info,admin}
Set the action to be taken. backup and restore are
self explanatory, info is used to retrieve info from
the storage media, while maintenance is used to delete
old backups and other admin actions. Default backup.
-F SRC_FILE, --path-to-backup SRC_FILE, --file-to-backup SRC_FILE
The file or directory you want to back up to Swift
-N BACKUP_NAME, --backup-name BACKUP_NAME
The backup name you want to use to identify your
backup on Swift
-m MODE, --mode MODE Set the technology to back from. Options are, fs
(filesystem), mongo (MongoDB), mysql (MySQL). Default
set to fs
-C CONTAINER, --container CONTAINER
The Swift container used to upload files to
-L, --list-containers
List the Swift containers on remote Object Storage
Server
-l, --list-objects List the Swift objects stored in a container on remote
Object Storage Server.
-o OBJECT, --get-object OBJECT
The Object name you want to download on the local file
system.
-d DST_FILE, --dst-file DST_FILE
The file name used to save the object on your local
disk and upload file in swift
--lvm-auto-snap LVM_AUTO_SNAP
Automatically guess the volume group and volume name
for given PATH.
--lvm-srcvol LVM_SRCVOL
Set the lvm volume you want to take a snaphost from.
Default no volume
--lvm-snapname LVM_SNAPNAME
Set the lvm snapshot name to use. If the snapshot name
already exists, the old one will be used a no new one
will be created. Default freezer_backup_snap.
--lvm-snapsize LVM_SNAPSIZE
Set the lvm snapshot size when creating a new
snapshot. Please add G for Gigabytes or M for
Megabytes, i.e. 500M or 8G. Default 5G.
--lvm-dirmount LVM_DIRMOUNT
Set the directory you want to mount the lvm snapshot
to. Default not set
--lvm-volgroup LVM_VOLGROUP
Specify the volume group of your logical volume. This
is important to mount your snapshot volume. Default
not set
--max-level MAX_BACKUP_LEVEL
Set the backup level used with tar to implement
incremental backup. If a level 1 is specified but no
level 0 is already available, a level 0 will be done
and subesequently backs to level 1. Default 0 (No
Incremental)
--always-level ALWAYS_BACKUP_LEVEL
Set backup maximum level used with tar to implement
incremental backup. If a level 3 is specified, the
backup will be executed from level 0 to level 3 and to
that point always a backup level 3 will be executed.
It will not restart from level 0. This option has
precedence over --max-backup-level. Default False
(Disabled)
--restart-always-level RESTART_ALWAYS_BACKUP
Restart the backup from level 0 after n days. Valid
only if --always-level option if set. If --always-
level is used together with --remove-older-then, there
might be the chance where the initial level 0 will be
removed Default False (Disabled)
-R REMOVE_OLDER_THAN, --remove-older-then REMOVE_OLDER_THAN
Checks in the specified container for object older
then the specified days. If i.e. 30 is specified, it
will remove the remote object older than 30 days.
Default False (Disabled)
--no-incremental Disable incremantal feature. By default freezer build
the meta data even for level 0 backup. By setting this
option incremental meta data is not created at all.
Default disabled
--hostname HOSTNAME Set hostname to execute actions. If you are executing
freezer from one host but you want to delete objects
belonging to another host then you can set this option
that hostname and execute appropriate actions. Default
current node hostname.
--mysql-conf MYSQL_CONF_FILE
Set the MySQL configuration file where freezer
retrieve important information as db_name, user,
password, host. Following is an example of config
file: # cat ~/.freezer/backup_mysql_conf host = <db-
host> user = <mysqluser> password = <mysqlpass>
--log-file LOG_FILE Set log file. By default logs to /var/log/freezer.log
--exclude EXCLUDE Exclude files, given as a PATTERN.Ex: --exclude
'*.log' will exclude any file with name ending with
.log. Default no exclude
--dereference-symlink {none,soft,hard,all}
Follow hard and soft links and archive and dump the
files they refer to. Default False.
-U, --upload Upload to Swift the destination file passed to the -d
option. Default upload the data
--encrypt-pass-file ENCRYPT_PASS_FILE
Passing a private key to this option, allow you to
encrypt the files before to be uploaded in Swift.
Default do not encrypt.
-M MAX_SEG_SIZE, --max-segment-size MAX_SEG_SIZE
Set the maximum file chunk size in bytes to upload to
swift Default 67108864 bytes (64MB)
--restore-abs-path RESTORE_ABS_PATH
Set the absolute path where you want your data
restored. Default False.
--restore-from-host RESTORE_FROM_HOST
Set the hostname used to identify the data you want to
restore from. If you want to restore data in the same
host where the backup was executed just type from your
shell: "$ hostname" and the output is the value that
needs to be passed to this option. Mandatory with
Restore Default False.
--restore-from-date RESTORE_FROM_DATE
Set the absolute path where you want your data
restored. Please provide datime in forma "YYYY-MM-
DDThh:mm:ss" i.e. "1979-10-03T23:23:23". Make sure the
"T" is between date and time Default False.
--max-priority Set the cpu process to the highest priority (i.e. -20
on Linux) and real-time for I/O. The process priority
will be set only if nice and ionice are installed
Default disabled. Use with caution.
-V, --version Print the release version and exit