Unsolved
This post is more than 5 years old
48 Posts
0
1599
SRDF/S DR scenario
In SRDF/S Disaster Recovery tests, what scenario should I choose. (DMX-3, mainframe environment, SRDF/S, no AUTOSWAP)
I would like to know any comments and suggestions about method of DR tests.
In documentation EMC recommends in SRDF/S (R1>R2)
following scenario:
1. make R1 NRDY
2. make R2 R/W
3. perform tests on R2 site (volumes)
4. optionally PREFRESH and PRE-RSUM changed tracks from R2 to R1
5. when test is finish, make R2 R/O, REFRESH R1 volumes from R2 volumes and finally resume ¿original¿ SRDF (RFR-RSUM)
In this scenario, application should be stopped (IPL-ed) twice and it is for me acceptable. During the test I haven¿t synchronization between R2 and R1 (I can only periodically PREFRESH and PRE-RSUM changed tracks). Advantage is that I can use any resynchronization method: form R2>R1 or R1>R2, full or tracks
In this case, why EMC don¿t recommend following scenario:
1. stop any I/O to volumes on R1 site
2. check that all volumes are in SYNC, no ADcopy, etc.
3. RDF-SUSP (R1>R2)
4. DELETEPAIR (R1>R2)
5. CREATEPAIR(NOCOPY) R2>R1
6. start tests and R/W activity on R2 site
7. when test is finish - stop application on R2 site and other I/O, make R2 R/O etc.,
8. RDF-SUSP (R2>R1)
9. DELETEPAIR (R2>R1)
10. CREATEPAIR(NOCOPY) R1>R2
11. start application on R1 site
In this scenario I take me own responsibility for consistency data during ¿NOCOPY¿ synchronization, but during tests (except two stops) I still have SRDF/S synchronization.
Any comments, pros and cons ?
Marcin
I would like to know any comments and suggestions about method of DR tests.
In documentation EMC recommends in SRDF/S (R1>R2)
following scenario:
1. make R1 NRDY
2. make R2 R/W
3. perform tests on R2 site (volumes)
4. optionally PREFRESH and PRE-RSUM changed tracks from R2 to R1
5. when test is finish, make R2 R/O, REFRESH R1 volumes from R2 volumes and finally resume ¿original¿ SRDF (RFR-RSUM)
In this scenario, application should be stopped (IPL-ed) twice and it is for me acceptable. During the test I haven¿t synchronization between R2 and R1 (I can only periodically PREFRESH and PRE-RSUM changed tracks). Advantage is that I can use any resynchronization method: form R2>R1 or R1>R2, full or tracks
In this case, why EMC don¿t recommend following scenario:
1. stop any I/O to volumes on R1 site
2. check that all volumes are in SYNC, no ADcopy, etc.
3. RDF-SUSP (R1>R2)
4. DELETEPAIR (R1>R2)
5. CREATEPAIR(NOCOPY) R2>R1
6. start tests and R/W activity on R2 site
7. when test is finish - stop application on R2 site and other I/O, make R2 R/O etc.,
8. RDF-SUSP (R2>R1)
9. DELETEPAIR (R2>R1)
10. CREATEPAIR(NOCOPY) R1>R2
11. start application on R1 site
In this scenario I take me own responsibility for consistency data during ¿NOCOPY¿ synchronization, but during tests (except two stops) I still have SRDF/S synchronization.
Any comments, pros and cons ?
Marcin
Notach
21 Posts
0
May 6th, 2009 01:00
for testing R2, we use Autoswap (since 2006), but before we must use R2 and use EMC procedure only one time.
Just to understand what you want to do. If it's just to test R2 by stopping activity and restart On R1 after test or you stop activity on R1, restart by IPl-ing partitions, use R2 and after test restart production on R1 after refreshing from R2.
In anycase, it's not necessary to deletepair and re-create them. Just takecare when you restart SRDF. If you want to activate SRDF always R1>R2 you can use personalityswap on R1 and R2.
Deletepair is fast, but create pair is a bit slower and if you have many thousand dasd you save up time in your Test and eliminate risk on the appairage.
after stopping SRDF/S for a test, it's preferabale to relauch SRDF in AD mode for better response time especially if you have many invalid tracks and your applicatins are critical.
PS:
before using R2 in R/W you must change their status in ready mode before changing status in R/W.
have a nice test...
Message was edited by:
Notach
WillemV1
18 Posts
0
May 13th, 2009 00:00
[1] Perform a Consistent Split
[2] IPL and run your DR-test
[3] RE-ESTABLISH the BCVs.
True, you'll need an extra set of volumes (BCVs) and of course, this is going to cost you. However, you'll be able to do DR-testing without interrupting your remotecopy. To us this was VERY important, important enough to get the extra volumes.
Roscoe95
2 Posts
0
June 19th, 2009 07:00