Chapter 11. Backing up Satellite Server and Capsule Server
You can back up your Satellite deployment to ensure the continuity of your Red Hat Satellite deployment and associated data in the event of a disaster. If your deployment uses custom configurations, you must consider how to handle these custom configurations when you plan your backup and disaster recovery policy.
If you create a new instance of the Satellite Server, decommission the old instances after restoring the backup. Cloned instances are not supposed to run in parallel in a production environment.
To create a backup of your Satellite Server or Capsule Server and all associated data, use the satellite-maintain backup
command. Backing up to a separate storage device on a separate system is highly recommended.
Satellite services are unavailable during the backup. Therefore, you must ensure that no other tasks are scheduled by other administrators. You can schedule a backup using cron
. For more information, see the Section 11.5, “Example of a weekly full backup followed by daily incremental backups”.
During offline or snapshot backups, the services are inactive and Satellite is in a maintenance mode. All the traffic from outside on port 443 is rejected by a firewall to ensure there are no modifications triggered.
A backup contains sensitive information from the /root/ssl-build
directory. For example, it can contain hostnames, ssh keys, request files and SSL certificates. You must encrypt or move the backup to a secure location to minimize the risk of damage or unauthorized access to the hosts.
Conventional backup methods
You can also use conventional backup methods. For more information, see Recovering and restoring a system in Red Hat Enterprise Linux 8 Configuring basic system settings.
If you plan to use the satellite-maintain backup
command to create a backup, do not stop Satellite services.
When creating a snapshot or conventional backup, you must stop all services as follows:
# satellite-maintain service stop
Start the services after creating a snapshot or conventional backup:
# satellite-maintain service start
11.1. Estimating the size of a backup
The full backup creates uncompressed archives of PostgreSQL and Pulp database files, and Satellite configuration files. Compression occurs after the archives are created to decrease the time when Satellite services are unavailable.
A full backup requires space to store the following data:
- Uncompressed Satellite database and configuration files
- Compressed Satellite database and configuration files
- An extra 20% of the total estimated space to ensure a reliable backup
Procedure
Enter the
du
command to estimate the size of uncompressed directories containing Satellite database and configuration files:# du -sh /var/lib/pgsql/data /var/lib/pulp 100G /var/lib/pgsql/data 100G /var/lib/pulp # du -csh /var/lib/tftpboot /etc /root/ssl-build \ /var/www/html/pub /opt/puppetlabs 16M /var/lib/tftpboot 37M /etc 900K /root/ssl-build 100K /var/www/html/pub 2M /opt/puppetlabs 942M total
Calculate how much space is required to store the compressed data.
The following table describes the compression ratio of all data items included in the backup:
Table 11.1. Backup data compression ratio Data type Directory Ratio Example results PostgreSQL database files
/var/lib/pgsql/data
80 – 85%
100 GB
20 GB Pulp RPM files
/var/lib/pulp
(not compressed)
100 GB
Configuration files
/var/lib/tftpboot
/etc
/root/ssl-build
/var/www/html/pub
/opt/puppetlabs
85%
942 MB
141 MB In this example, the compressed backup data occupies 120 GB in total.
To calculate the amount of available space you require to store a backup, calculate the sum of the estimated values of compressed and uncompressed backup data, and add an extra 20% to ensure a reliable backup.
This example requires 201 GB plus 120 GB for the uncompressed and compressed backup data, 321 GB in total. With 64 GB of extra space, 385 GB must be allocated for the backup location.
11.2. Performing a full backup of Satellite Server or Capsule Server
Red Hat Satellite uses the satellite-maintain backup
command to make backups.
There are three main methods of backing up Satellite Server:
- Offline backup
- Online backup
Snapshot backups
For more information about each of these methods, you can view the usage statements for each backup method.
Offline backups
# satellite-maintain backup offline --help
Online backups
# satellite-maintain backup online --help
Snapshots backups
# satellite-maintain backup snapshot --help
Directory creation
The satellite-maintain backup
command creates a time-stamped subdirectory in the backup directory that you specify. The satellite-maintain backup
command does not overwrite backups, therefore you must select the correct directory or subdirectory when restoring from a backup or an incremental backup. The satellite-maintain backup
command stops and restarts services as required.
When you run the satellite-maintain backup offline
command, the following default backup directories are created:
-
satellite-backup
on Satellite -
foreman-proxy-backup
on Capsule
If you want to set a custom directory name, add the --preserve-directory
option and add a directory name. The backup is then stored in the directory you provide in the command line. If you use the --preserve-directory
option, no data is removed if the backup fails.
Note that if you use a local PostgreSQL database, the postgres
user requires write access to the backup directory.
Remote databases
You can use the satellite-maintain backup
command to back up remote databases.
You can use both online and offline methods to back up remote databases, but if you use offline methods, such as snapshot, the satellite-maintain backup
command performs a database dump.
Backing up to a remote NFS share
To enable Satellite to save the backup to an NFS share, ensure that the root
user of your Satellite Server or Capsule Server can write to the NFS share. NFS export options such as root_squash
and all_squash
are known to prevent this.
For more information, see Red Hat Enterprise Linux Configuring and using network files services and Red Hat Enterprise Linux Securing network services.
Prerequisites
- Ensure that your backup location has sufficient available disk space to store the backup. For more information, see Section 11.1, “Estimating the size of a backup”.
Request other users of Satellite Server or Capsule Server to save any changes and warn them that Satellite services are unavailable for the duration of the backup. Ensure no other tasks are scheduled for the same time as the backup.
Procedure
On Satellite Server, enter the following command:
# satellite-maintain backup offline /var/satellite-backup
On Capsule Server, enter the following command:
# satellite-maintain backup offline /var/foreman-proxy-backup
11.3. Performing a backup without Pulp content
You can perform an offline backup that excludes the contents of the Pulp directory. The backup without Pulp content is useful for debugging purposes and is only intended to provide access to configuration files without backing up the Pulp database. For production usecases, do not restore from a directory that does not contain Pulp content.
Request other users of Satellite Server or Capsule Server to save any changes and warn them that Satellite services are unavailable for the duration of the backup. Ensure no other tasks are scheduled for the same time as the backup.
Prerequisites
- Ensure that your backup location has sufficient available disk space to store the backup. For more information, see Section 11.1, “Estimating the size of a backup”.
Procedure
To perform an offline backup without Pulp content, enter the following command:
# satellite-maintain backup offline --skip-pulp-content /var/backup_directory
11.4. Performing an incremental backup
Use this procedure to perform an offline backup of any changes since a previous backup.
To perform incremental backups, you must perform a full backup as a reference to create the first incremental backup of a sequence. Keep the most recent full backup and a complete sequence of incremental backups to restore from.
Request other users of Satellite Server or Capsule Server to save any changes and warn them that Satellite services are unavailable for the duration of the backup. Ensure no other tasks are scheduled for the same time as the backup.
Prerequisites
- Ensure that your backup location has sufficient available disk space to store the backup. For more information, see Section 11.1, “Estimating the size of a backup”.
Procedure
To perform a full offline backup, enter the following command:
# satellite-maintain backup offline /var/backup_directory
To create a directory within your backup directory to store the first incremental back up, enter the
satellite-maintain backup
command with the--incremental
option:# satellite-maintain backup offline --incremental /var/backup_directory/full_backup /var/backup_directory
To create the second incremental backup, enter the
satellite-maintain backup
command with the--incremental
option and include the path to the first incremental backup to indicate the starting point for the next increment. This creates a directory for the second incremental backup in your backup directory:# satellite-maintain backup offline --incremental /var/backup_directory/first_incremental_backup /var/backup_directory
Optional: If you want to point to a different version of the backup, and make a series of increments with that version of the backup as the starting point, you can do this at any time. For example, if you want to make a new incremental backup from the full backup rather than the first or second incremental backup, point to the full backup directory:
# satellite-maintain backup offline --incremental /var/backup_directory/full_backup /var/backup_directory
11.5. Example of a weekly full backup followed by daily incremental backups
The following script performs a full backup on a Sunday followed by incremental backups for each of the following days. A new subdirectory is created for each day that an incremental backup is performed. The script requires a daily cron job.
#!/bin/bash -e PATH=/sbin:/bin:/usr/sbin:/usr/bin DESTINATION=/var/backup_directory if [[ $(date +%w) == 0 ]]; then satellite-maintain backup offline --assumeyes $DESTINATION else LAST=$(ls -td -- $DESTINATION/*/ | head -n 1) satellite-maintain backup offline --assumeyes --incremental "$LAST" $DESTINATION fi exit 0
Note that the satellite-maintain backup
command requires /sbin
and /usr/sbin
directories to be in PATH
and the --assumeyes
option is used to skip the confirmation prompt.
11.6. Performing an online backup
Perform an online backup only for debugging purposes.
Risks associated with online backups
When performing an online backup, if there are procedures affecting the Pulp database, the Pulp part of the backup procedure repeats until it is no longer being altered. Because the backup of the Pulp database is the most time consuming part of backing up Satellite, if you make a change that alters the Pulp database during this time, the backup procedure keeps restarting.
For production environments, use the snapshot method. For more information, see Section 11.7, “Performing a snapshot backup”. If you want to use the online backup method in production, proceed with caution and ensure that no modifications occur during the backup.
Request other users of Satellite Server or Capsule Server to save any changes and warn them that Satellite services are unavailable for the duration of the backup. Ensure no other tasks are scheduled for the same time as the backup.
Prerequisites
- Ensure that your backup location has sufficient available disk space to store the backup. For more information, see Section 11.1, “Estimating the size of a backup”.
Procedure
To perform an online backup, enter the following command:
# satellite-maintain backup online /var/backup_directory
11.7. Performing a snapshot backup
You can perform a snapshot backup that uses Logical Volume Manager (LVM) snapshots of the Pulp, and PostgreSQL directories. Creating a backup from LVM snapshots mitigates the risk of an inconsistent backup.
The snapshot backup method is faster than a full offline backup and therefore reduces Satellite downtime.
To view the usage statement, enter the following command:
# satellite-maintain backup snapshot -h
Request other Satellite Server or Capsule Server users to save any changes and warn them that Satellite services are unavailable for the duration of the backup. Ensure no other tasks are scheduled for the same time as the backup.
Prerequisites
-
The system uses LVM for the directories that you snapshot:
/var/lib/pulp/
and/var/lib/pgsql
. - The free disk space in the relevant volume group (VG) is three times the size of the snapshot. More precisely, the VG must have enough space unreserved by the member logical volumes (LVs) to accommodate new snapshots. In addition, one of the LVs must have enough free space for the backup directory.
- The target backup directory is on a different LV than the directories that you snapshot.
Procedure
To perform a snapshot backup, enter the
satellite-maintain backup snapshot
command:# satellite-maintain backup snapshot /var/backup_directory
The satellite-maintain backup snapshot
command creates snapshots when the services are active, and stops all services which can impact the backup. This makes the maintenance window shorter. After the successful snapshot, all services are restarted and LVM snapshots are removed.
11.8. Skipping steps when performing backups
A backup using the satellite-maintain backup
command proceeds in a sequence of steps. To skip part of the backup, add the --whitelist
option to the command and the step label that you want to omit.
Procedure
To display a list of available step labels, enter the following command:
# satellite-maintain advanced procedure run -h
To skip a step of the backup, enter the
satellite-maintain backup
command with the--whitelist
option. For example:# satellite-maintain backup online \ --whitelist backup-metadata \ /var/backup_directory