Disaster Recovery Questions regarding DB2

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Disaster Recovery Questions regarding DB2
Hi everyone!

Our company is trying to make a DR(Disaster Recovery) plan using an Asynchronous Remote copy solution among XRC, SRDF Adaptive copy, HARC and so on.

- Our system configuration: OS/390, CICS, DB2 etc.

- The overall scenario of our DR plan

#1 Log and BSDS is transferred realtime to the backup center disk using Asynchronous Remote copy solution

#2 Catalog and DB(Database) is replicated to the backup center disk during the night after DB2 is normally stopped.

#3 If a disaster occurs, the data will be recovered using RECOVER utility with LOGONLY option at a Backup Center.


Question 1: I was told that there is a chance that DB2 cannot restart normally in the event of a disaster. Is this true?

As far as we know, in this case, Conditional Restart(including Cold Start) is needed instead.

Question 2: We wonder whether or not the jobs in the box below can be run successfully, after the Conditional Restart(including Cold Start) is done.

======================
//SYSIN DD *
RECOVERY TABLESPACE A.B LOGONLY TORBA(x'70')

<Condition>
- The Highest Written Log RBA : x'200'
- Cold Start RBA(Startrba=Endrba) : x'400'
- Tablespace A.B Highest Log RBA : x'50'
=======================

I would really appreciate it, if you could give me kindly explanations to these questions.

Question 3: Besides, although I only cited 'Cold Start' as an example, I hope you would telling me more about the 'Conditional Restart' case, too.

Thank you in advance,

Best regards,



Edward Vassie

Re: Disaster Recovery Questions regarding DB2
(in response to cwpark@SAMSUNG.CO.KR)
If DB2 is stopped when you replicate the catalog and database, I can see no
reason why it should not restart normally. As far as DB2 is concerned, it
will not know if it is being restarted at the home site or at the recovery
site, and should behave in the same manner at both locations.

If DB2 is active when you replicate the catalog and database, then you may
well get some problems.

From Edward Vassie...


-----Original Message-----
From: [login to unmask email] [mailto:[login to unmask email]
Sent: 05 January 2001 12:46
To: [login to unmask email]
Subject: Disaster Recovery Questions regarding DB2


Hi everyone!

Our company is trying to make a DR(Disaster Recovery) plan using an
Asynchronous Remote copy solution among XRC, SRDF Adaptive copy, HARC and so
on.

- Our system configuration: OS/390, CICS, DB2 etc.

- The overall scenario of our DR plan

#1 Log and BSDS is transferred realtime to the backup center disk
using Asynchronous Remote copy solution

#2 Catalog and DB(Database) is replicated to the backup center disk
during the night after DB2 is normally stopped.

#3 If a disaster occurs, the data will be recovered using RECOVER
utility with LOGONLY option at a Backup Center.


Question 1: I was told that there is a chance that DB2 cannot restart
normally in the event of a disaster. Is this true?

As far as we know, in this case, Conditional Restart(including Cold Start)
is needed instead.

Question 2: We wonder whether or not the jobs in the box below can be run
successfully, after the Conditional Restart(including Cold Start) is done.

======================
//SYSIN DD *
RECOVERY TABLESPACE A.B LOGONLY TORBA(x'70')

<Condition>
- The Highest Written Log RBA : x'200'
- Cold Start RBA(Startrba=Endrba) : x'400'
- Tablespace A.B Highest Log RBA : x'50'
=======================

I would really appreciate it, if you could give me kindly explanations to
these questions.

Question 3: Besides, although I only cited 'Cold Start' as an example, I
hope you would telling me more about the 'Conditional Restart' case, too.

Thank you in advance,

Best regards,








Piontkowski Michael ML

Re: Disaster Recovery Questions regarding DB2
(in response to Edward Vassie)
The key point is that the BSDS, Log, DB2 Catalog, ICF Catalog, DASD VTOCs,
Tape Mgmt System database must be in sync. The recovery is much simpler.
Making copies while DB2 is down also keeps the recovery simple.


Mike Piontkowski
TP&S Technical Maintenance
Voice: +1 302.886.4612
Fax: +1 302.886.4749


-----Original Message-----
From: [login to unmask email] [mailto:[login to unmask email]
Sent: Friday, January 05, 2001 7:46
To: [login to unmask email]
Subject: [DB2-L] Disaster Recovery Questions regarding DB2


Hi everyone!

Our company is trying to make a DR(Disaster Recovery) plan using an
Asynchronous Remote copy solution among XRC, SRDF Adaptive copy, HARC and so
on.

- Our system configuration: OS/390, CICS, DB2 etc.

- The overall scenario of our DR plan

#1 Log and BSDS is transferred realtime to the backup center disk
using Asynchronous Remote copy solution

#2 Catalog and DB(Database) is replicated to the backup center disk
during the night after DB2 is normally stopped.

#3 If a disaster occurs, the data will be recovered using RECOVER
utility with LOGONLY option at a Backup Center.


Question 1: I was told that there is a chance that DB2 cannot restart
normally in the event of a disaster. Is this true?

As far as we know, in this case, Conditional Restart(including Cold Start)
is needed instead.

Question 2: We wonder whether or not the jobs in the box below can be run
successfully, after the Conditional Restart(including Cold Start) is done.

======================
//SYSIN DD *
RECOVERY TABLESPACE A.B LOGONLY TORBA(x'70')

<Condition>
- The Highest Written Log RBA : x'200'
- Cold Start RBA(Startrba=Endrba) : x'400'
- Tablespace A.B Highest Log RBA : x'50'
=======================

I would really appreciate it, if you could give me kindly explanations to
these questions.

Question 3: Besides, although I only cited 'Cold Start' as an example, I
hope you would telling me more about the 'Conditional Restart' case, too.

Thank you in advance,

Best regards,








Michael Murley

Re: Disaster Recovery Questions regarding DB2
(in response to Piontkowski Michael ML)
.

I can't immediately see any reason that you would need to do a conditional
restart in this scenario. You will need to use DEFER(ALL) in the DSNZPARM
setting, though. Otherwise, when DB2 restarts, it will try to apply log
records to the spaces as they existed at the point of failure. Since the
spaces were copied the night before, they will not be in the right state for
those log records to be applied until you do the LOGONLY recovery.

What do you plan to do with indexes ? Do you plan to copy them while DB2 is
down, too ? REBUILDing them all may be quite expensive. If you have BMC
RECOVER PLUS for DB2*, you should consider a LOGONLY recovery of any really
large your type 2 indexes as well. If you don't have the BMC product, but
you're running DB2 V6, you might consider defining some of your really large
indexes as COPY YES so you could LOGONLY recover them and avoid the long
rebuild times.

Just some things to consider.

Michael Murley
BMC

-----Original Message-----
From: [login to unmask email] [mailto:[login to unmask email]
Sent: Friday, January 05, 2001 6:46 AM
To: [login to unmask email]
Subject: Disaster Recovery Questions regarding DB2


Hi everyone!

Our company is trying to make a DR(Disaster Recovery) plan using an
Asynchronous Remote copy solution among XRC, SRDF Adaptive copy, HARC and so
on.

- Our system configuration: OS/390, CICS, DB2 etc.

- The overall scenario of our DR plan

#1 Log and BSDS is transferred realtime to the backup center disk
using Asynchronous Remote copy solution

#2 Catalog and DB(Database) is replicated to the backup center disk
during the night after DB2 is normally stopped.

#3 If a disaster occurs, the data will be recovered using RECOVER
utility with LOGONLY option at a Backup Center.


Question 1: I was told that there is a chance that DB2 cannot restart
normally in the event of a disaster. Is this true?

As far as we know, in this case, Conditional Restart(including Cold Start)
is needed instead.

Question 2: We wonder whether or not the jobs in the box below can be run
successfully, after the Conditional Restart(including Cold Start) is done.

======================
//SYSIN DD *
RECOVERY TABLESPACE A.B LOGONLY TORBA(x'70')

<Condition>
- The Highest Written Log RBA : x'200'
- Cold Start RBA(Startrba=Endrba) : x'400'
- Tablespace A.B Highest Log RBA : x'50'
=======================

I would really appreciate it, if you could give me kindly explanations to
these questions.

Question 3: Besides, although I only cited 'Cold Start' as an example, I
hope you would telling me more about the 'Conditional Restart' case, too.

Thank you in advance,

Best regards,