DB2 Incremental Image Copy Jobs

raghav08 · New User Joined: 03 Jun 2008 Posts: 94 Location: Bangalore

Hello.

Please let me know- How the DB2 incremental image copy jobs are working to take (or down load)only the changed pages since from last image copy recorded in DB2 SYSCOPY.

We use utility program DSNUTILB with SYSIN
COPY TABLESPACE xxx FULL NO SHRLEVEL CHANGE DSNUM nn

Thanks in advance

dick scherrer · Posted: Thu Mar 25, 2010 9:16 pm

Hello,

Suggest you add some clarification as to what you are looking for. . .

An incremental backup is just that - information changed since the previous backup. . .

Probably, there is something i am missing.

guptae · Posted: Fri Mar 26, 2010 11:52 am

Hello Raghav,

Generally for incremental Image copy does not require a complete scan for Tablespace except:
1. tablespace defined as TRACKMOD NO
2. First image copy after Altering TS to TRACKMOD YES

Spacemap for each TS for each page regardless whether its changed for last image copy.Incremental image copies of a table space that is defined
with TRACKMOD NO still saves space, although the performance advantage is
smaller.

Hope it will helpful

raghav08 · New User Joined: 03 Jun 2008 Posts: 94 Location: Bangalore

Hello.

I'm looking forward to know -

1) How the utility program works to recognize the changed pages since from previous backup (how it compares the current data in the tablespace with previous backup data)

2) Is the utility program refers any of the DB2 catalog tables to identify the changed pages? If yes, please explain

guptae · Posted: Fri Mar 26, 2010 3:48 pm

Hello Raghav,

That was I explained in my prev post. It refer the spacemap to identify
whether the pagE was changed from the last image copy if it is defined as TRACKMOD YES.

raghav08 · New User Joined: 03 Jun 2008 Posts: 94 Location: Bangalore

Hello Ekta,

Thanks for your information, as you mentioned about TRACKMOD (YES/NO), I found some more information on this.

Thanks
Raghav08