One of the frustrations about having a High Availability setup is that unless something drastic happens, you may never use it. It will only go live if you have an unexpected outage on your source box, for testing, or if you need to switch processing to it for an extended planned outage (migration to a new box, moving locations, etc.)
An HA box is an insurance policy against the unexpected; one that’s usually not intended to be productive day-to-day.
But what if you want to make your HA setup more productive and get some value out of that machine that’s just sitting there replicating all day?
In that spirit, here are five things you can try to make your HA setup more productive without losing its ability to function as a backup machine.
- Use the HA box to replace your backups – This should be a no-brainer, but surprisingly it isn’t with many shops. Since you’ve already set up an (almost) exact duplicate of your production box that should be ready to go at a moment’s notice, you should be able to use it to back up your data and configurations. Which will free up your production box to run 24×7. You’ll still need to schedule production system backups once or twice a year but having an HA setup can pretty much free you up from taking down your production box for backups.
- Run data audits and reports off your HA box – Several pieces of database auditing software such as Raz-Lee’s AP Journal, can be set up to use your HA configuration for their monitoring and alert activities. By using your HA box to monitor for database exceptions, you take advantage of its unused production cycles. The auditing work is completed without using CPU cycles on your production machine. Since reporting and monitoring software never updates data, your HA box can become a co-server, freeing up your production server for actually processing data.
- Carve out a sandbox – Since you’re probably not using the full capacity of your HA box, you may be able to create a small partition to perform processing you can’t or don’t want to do on your production or development partitions. Is your shop running IBM i 6.1 and you want to test i 7.1? Create a small sandbox partition to practice restoring/upgrading to 7.1. Need a place to keep an unmodified copy of vendor source code for checking the effects of testing? Use a sandbox. Want to play with some software or a feature that can’t currently run on your prod or dev environment. Create and use a sandbox. Sandbox processing is typically only used by a small subset of users so you don’t need many resources. And it can help you try things you’re not free to do on a live box. By putting your sandbox on your HA box, you’re again taking advantage of unused capability and processing cycles.
- Replicate your development, Web, or other IBM i partition environment – Many HA setups replicate production partitions but don’t have plans to switchover development processing or Web partitions, if those partitions become unavailable. So in a disaster where you lose both your production and development environments, your developers may have to scramble to keep working or your Web sites will stop working. An HA dev or Web environment might be called for in this case.
- Migration to a new machine in an upgrade – Many HA software vendors such as Vision Solutions, can help migrate your existing production partitions to a new environment through replication rather than solely performing a bare metal restore. When it’s time to restore, you keep your existing production machine up as long as possible and when it’s time to switch to the new hardware, you perform a fail over switch rather than a restore. I’ll be talking more about this capability in an upcoming January IT Jungle column.
Check with IBM or your business partner before implementing any of these options that require licensing either by IBM or by a third-partner software vendor. In some instances, IBM sells their HA configurations at a discount with the stipulation that they are not to be used for production processing. If you bought a high-availability machine under these terms, that may limit what you can do with your HA box outside of using it as a replicated backup.
Also note that some of these options such as additional HA partitions or running database auditing or reporting software, may require additional licensing from your vendors.
Good points Joe, but many customers in Sweden are using IBM PowerHA (should be PowerDR if you ask me) and therefore are not able to use the backup environment without protection exposure.. And somtimes not at all (full system metro mirror). You can our course start using flashcopy etc, but then you are in a complex environment *immed
You’re right. As I said, they are not for everyone. In my shop, we use Mimix for system backups, the sandbox, and we are currently using it to migrate our HA to a new machine. So in the right situations, you can get more value and use out of an HA setup than you think.