You need a backup strategy to test your company’s disaster recovery plan, and despite its reputation for reliability, administrators still need to back up. A solid backup strategy should also restore the user’s individual objects to account for human errors. Seven save commands are required to successfully back up the system: SAVSYS, SAVCFG, SAVSECDTA, SAVLIB, SAVCHGOBJ, SAVDLO and SAV. Make the backup a quick download by familiarizing yourself with these save commands and the optimal frequency.

Save commands for your system

The System Save command (SAVSYS) is used to back up the licensed internal code, operating system, profiles, configuration objects, and object authorities and must be executed in a restricted state. SAVSYS is best done after hours or on weekends, usually once a month or after a major operating system update, after installing licensed programs, or after installing temporary program fixes (PTFs).

Save orders for your business data

The Save Library (SAVLIB) and Save Modified Objects (SAVCHGOBJ) commands back up data in the library file system. Use these two commands together to provide full backups of your libraries. SAVLIB backs up an entire library while SAVCHGOBJ backs up only objects that have changed since the last SAVLIB. How often you run these commands depends on how often a library changes. The best practice is to do a SAVCHGOBJ against data libraries, sources and programs daily and save all libraries completely using the SAVLIB command once a week.

Backup tips

In addition to save commands, use these tips to avoid common mistakes:

  • Use hardware devices of adequate capacity for backup
  • Use mirrored disk drives and RAID to reduce the chances of hardware failure
  • Use CBU systems for high availability and save on the secondary system
  • Use the IBM i log of physical files
  • Use the save function while it is active
  • Make backups when no one is using the system
  • Make sure you have an off-site storage facility for your multimedia content
  • Incorporate virtual tape libraries (VTLs) and avoid off-site all together
  • Maintain multiple rotations or similar backup generations
  • Keep your security profiles in a safe place
  • Maintain a control language (CLP) procedure for any changes you have made to IBM i that can be called to restore those changes if you need to restore to another system
  • Automate restricted status operations with your own or purchased software

Performance concerns

As a backup administrator, you need to be aware of the parameters that affect performance and try to change them to get the most out of your system with as little downtime as possible. The faster the processor and tape drive, the faster the backups, but not everyone can afford to buy a bigger system. However, a new tape drive or VTL can be a good investment. The SSD will also speed up backups.

Data size, types and number of objects affect the speed of backups. Multi-member objects are often slower to back up than a single large object. Try splitting your backups into multiple backup jobs. Or simply back up only the object libraries that change instead of all libraries. Both are ways to reduce the number of objects you back up. Restricted status is the fastest way to back up any library, because the operating system does not have to check for object locks. It is only assumed that the library is completely free for a backup operation.

Given these tools and considerations, test your backup strategy.