RE: save while active v7r1 - *IBM and also SAV

Hi Jim

In your first post discussing journaling you stated.

In a PowerHA environment it's essential to ensure properly managed HA
clusters.
(the same is true for the journal based replication packages)

Just trying to understand the above in regard to journaling. Before
PowerHA existed back at V5R4, I setup HA using clustering and Geo
Mirroring. We were not journaling at the time. As far as I can tell
everything worked fine, even a couple of times when we went down hard and
had an automatic failover, we could find no missing or out of sync data.
Replicating *sysbas items took some time, but we made it work. Did
require some serious changes to our library list management structure.

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message: 1
date: Wed, 8 Apr 2015 17:04:54 -0500
from: "Horn, Jim" <jim.horn@xxxxxxxxxxxxxx>
subject: RE: save while active v7r1 - *IBM and also SAV

I haven't been responsible for this for a few years but -
sounds like this would make a good COMMON session.

In PowerHA do you need to be doing remote journaling?

Jim

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message: 1
date: Wed, 8 Apr 2015 14:39:14 -0500
from: "Jim Oberholtzer" <midrangel@xxxxxxxxxxxxxxxxx>
subject: RE: save while active v7r1 - *IBM and also SAV

Rob brings up a salient point. ALL of your applications should be
journaled, regardless of if you use them for commit control or not. It
aids
in speedier recovery from an abnormal termination, it aids in SWA, and if
set up properly with system managed journals, does not require

significant

administrative work to manage them. In a PowerHA environment it's
essential
to ensure properly managed HA clusters. (the same is true for the

journal

based replication packages)

Another way to get past most of the complexity is BRMS. BRMS manages

most

of the issues with respect to SWA nicely. The small investment in BRMS
will
pay for itself in administration time, and recoverability in very short
order.

Another reason to use journals is to mitigate the need for getting
checkpoints across multiple libraries at one time. Granted referential
integrity might not be perfect without a multiple library checkpoint but
using journaling by application rather than library boundary goes a long
way
to making that technique acceptable.

Very few of my customers have environments were the near restricted state
(however short) to achieve a synchronization point is required, rather by
using BRMS and good use of journaling you can achieve 98% of what you

what

without the shutdown pain.

--
Jim Oberholtzer
Chief Technical Architect
Agile Technology Architects


-----Original Message-----
From: MIDRANGE-L [mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of
rob@xxxxxxxxx
Sent: Wednesday, April 08, 2015 2:23 PM
To: Midrange Systems Technical Discussion
Subject: Re: save while active v7r1 - *IBM and also SAV

Jim,

I think you are a somewhat regular attendee of COMMON. That might be a
good
place to really bone up.

Some search terms are: ragged save while active.
I think that might be the title of a redbook by Larry Youngren

With little to no journalling you may catch some grief.

Stream files are very picky and snicker at save while active.

Until we did the Mimix thing and started backing up from that we were

doing

a crappy save while active. No checkpoint processing. No journalling.
Didn't care if order header was in sync with order line, etc
SAVACT(*SYSDFN). The goal being: You can back up, just don't disrupt

the

users from getting into the data. I argued against it but had to bide my
time until Mimix. Only took a few years...


Rob Berendt
--
IBM Certified System Administrator - IBM i 6.1 Group Dekko Dept 1600 Mail
to: 2505 Dekko Drive
Garrett, IN 46738
Ship to: Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com