RE: [External]Re: H/A Replication Vendors and Temporal Tables

As part of our PowerHA implementation we relocated our iASP from internal Power7 disk to V7000 SAN disk while the system was up and running.

All we had to do was define some SAN disk, add them to the existing iASP disk pool, and then remove the "internal" iASP disk from the disk configuration. When you remove a disk from a storage pool, the data is automatically moved to other disks in the pool. When all the internal iASP disk were removed, ALL the data had been migrated to the SAN.

We did this over a few days to minimize any disk related performance hit, but the system was up and running during the entire migration! No Save/Restore!

Having all your disk in a SAN lets you do some other neat stuff too.

On another one of our systems, where *SYSBAS was also in the SAN, we were able to clone the *SYSBAS disk, attach this disk to another partition as it's *SYSBAS and we had another IBMi partition all ready to go! Of course we had to change some of the software keys to account for a different partition number, but that was easy. Again... No Save/Restore!

You need to do some major application changes in your iASP and want a quick and easy backup just in case something goes terribly wrong? Set up a FLASHCOPY (a point-in-time image of the iASP in your production SAN) and start it, then do your upgrade. If you need to back out, use the FLASHCOPY to recover to the exact point-in-time just prior to the upgrade. No Save/Restore!

Want to backup your iASP data to tape without having to do it on your production system? Once you set up Global or Metro Mirroring using PowerHA, you can use PowerHA to automatically create a FLASHCOPY of the mirrored data on your DR target system, attach it to an IBMi partition set up for backups, and back everything to tape! No performance hit on the source system and your data is already off site even before you have it copied to tape!

Using PowerHA provides 3 levels of data protection. The mirror copy, a FLASHCOPY of the mirror copy and a tape BU of the mirror FLASHCOPY.

The mirrored copy is in real time (metro mirror) or close to real time (asynchronous global mirroring)and the FLASHCOPY is a point-in-time backup of the mirrored copy...

There have been times when a developer has asked me to recover a source file that he accidently deleted. In the past, I would have had to have a tape returned from our offsite storage vendor, and then restore the file. Now, all I have to do is save a copy of the file he deleted from the FLASHCOPY on the BU partition via a *SAVF, send it to the source and restore it. Recovery in a few minutes instead of hours!

Need to test a program that does a mass delete of records in a critical production file? After you have run your backup on the BU partition, you can test your process against a perfect copy of the production file and review the results before doing it in production... No problem because the FLASHCOPY attached to the BU partition can be "messed" with as needed because it will be completely REPLACED the next time PowerHA creates a new one...

I like having my IBMi data in a SAN and using PowerHA to protect it. I wish I had done this a long time ago!

Reply or Forwarded mail from: Kenneth E Graap


-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of DrFranken
Sent: Friday, September 09, 2016 5:46 AM
To: Midrange Systems Technical Discussion
Subject: [External]Re: H/A Replication Vendors and Temporal Tables

Rob,

There are 'Flavors' of PowerHA. One of them - GeoMirror uses internal disk and it's IBM i itself that is replicating the data. Which you chose depends on your needs, data size, and other factors. With SAN for example you can flash-copy but with internal disk you cannot.

With any flavor you can certainly switch over, do PTFs on production switch back, do PTFs on backup side. Or do the HA side first. Same with backups, upgrades. etc.

I have in fact used PowerHA to move customers from one server to another
(Power7 to Power8) and upgrade from IBM i 7.1 to 7.2 in the process. At one customer we did this on three separate PowerHA 'pairs'. All went very very smoothly. No Save/Restore needed!


- Larry "DrFranken" Bolhuis