Backup
Data Held on PhixFlow
The PhixFlow system is comprised of a database and systems files stored as follows:
Database |
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File system |
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Backup Options
At the planning phase of the deployment, the backup options should be determined based on:
- Recovery Time Objective (RTO): how long the recovery will take? (5 minutes / 1 hour?)
- Recovery Point Objective (RPO): for example, point-in-time recovery (PITR) or recovery to the overnight backup. For the latter, are you OK with losing data input entered today for example?
For more details on this topic see: https://en.wikipedia.org/wiki/Disaster_recovery_and_business_continuity_auditing
Application server backups
Perform an application backup each time PhixFlow is upgraded
Or weekly application server backups to simplify the process. Deleting old backups after N weeks.
Details of the solution have an impact on the need for backup and recovery of the application server. In most cases, the only data that must be kept for the integrity of the solution is in the database. In many cases, artifacts (software, template files, image files, uploaded files) and data (imported and exported files) kept on the application server can be recovered from other sources, or are not needed for long-term retention.
Discuss this with your PhixFlow implementation team or PhixFlow support to determine exactly what you need to retain for the long term, and what the recovery needs are for the application server.
It is usually important - and in some cases vital (e.g. corporate standards and/ or independent compliance frameworks may apply) to retain log files for a certain period of time. If you ingest your log files into an off-server log store, however, there may be no need to make provision for the backup and recovery of log files on the application server itself.
In many cases, a platform backup for the disk or server, of the type offered by many virtualisation solutions, will be sufficient, and this may not be needed as frequently as that for the database. Daily backup is typical, and not usually associated with much higher cost than a less frequent backup schedule.
Database server backups
Define the backup requirements for your RTO and RPO so that your Database Administrator (DBA) can best advise on a suitable backup strategy for your setup. For example, your requirements will influence the need for a "hot" backup (PITR)), or "cold" (Full backup daily).
Predicting "undo" and "redo" space is often difficult, and observing the solution at work is the best way of measuring the required amount of space. It is important to not over-specify the server and each partition to avoid unnecessary costs and grow these if needed once the solution has been established.
Some virtualisation platforms will support RPOs much shorter than standard snapshot/ backup options. For example, for running SQL Server on Azure: https://docs.microsoft.com/en-us/azure/backup/backup-azure-sql-database
Database backup volume planning
If you opt for database-level backups (rather than backups on a virtualisation layer), you will need to plan for additional disk storage. However, for long-term retention of these backups, you can use a lower cost disk. These sizings are only indicative, and the exact amount you need will depend on the details of your solution.
Weekly backup volume | Small | Medium | Large |
"Cold" backups - i.e. full backups only | 25 GB | 100 GB | 400 GB |
"Hot" backups - redo backups for PITR | 50 GB | 200 GB | 800 GB |
Total | 75 GB | 300 GB | 1200 GB |
General recommendations
- If you are working on a virtualisation platform, make use of the backup options available if you can - these are often more straightforward to manage, recover from, and test recovery from, than traditional database backups.
- If you are using snapshot technology to take backups - that is, backing up disks that are not idle - choose application consistent snapshots/ backups if possible.