MIRRORLOGPATH

[DB2 Convert]

Hi

Two questions:
1. what is the maximum mirror log that can be set?

2. Say I have a media failure and some or the entire
Node0000\SQL00001 directory is gone while database is up and running.
Is my only option at that moment to restore online redirect? Can I
restore a particular file instead of an online restore of the entire
database? When you do an online backup, what are backed up anyways?
Thanks
DB2 Convert

[Pierre Saint-Jacques]

See below

DB2 Convert wrote:

Hi

Two questions:
1. what is the maximum mirror log that can be set? Same limit as the normal logpath. Typically, your limit is the file
system limit. Your maximum active logging is 256GB in V8.
2. Say I have a media failure and some or the entire
Node0000\SQL00001 directory is gone while database is up and running.
Is my only option at that moment to restore online redirect? Can I
restore a particular file instead of an online restore of the entire
database? When you do an online backup, what are backed up anyways? What goes in the backup image is only limited by the command. Full db
backup offline or online contain exactly the same thing. Tablespace
(single or multiple) backups will contain the same thing wether online
or offline as long as they specify the same tablespaces.

If you damage the Recovery History File in the database directory
SQL00001 then it can be restored selectively from your most recent backup.
If lyou loose or damage any of the other files, you will have to restore
the full db offline and rool it forward to end og logs to recover these
files.

You cannot ever restore a full db image online. It is required to
restore always offline.
If the drive or path is so damaged that you can't restore where it cam
from the resotre command allows you to restore to a different path.

The redirect option you mention only serves to redirect or rather
relocate containers of your tablespaces.

HTH, Pierre.

Thanks
DB2 Convert

--
Pierre Saint-Jacques - Reply to: sesconsjunk at attglobaljunk dot com
Reconstruct address: Remove the two junk and replace at and dot by
their symbols.
IBM DB2 Cerified Solutions Expert - Administration
SES Consultants Inc.

[DB2 Convert]

Pierre Saint-Jacques <se*****@attglobal.net> wrote in message news:<40**************@attglobal.net>...

See below

DB2 Convert wrote:

Hi

Two questions:
1. what is the maximum mirror log that can be set? Same limit as the normal logpath. Typically, your limit is the file
system limit. Your maximum active logging is 256GB in V8.

Are you saying that I can have 200 or more mirrorlogpaths? Why isn't
an upper limit for this config parameter. No one will ever need a 200
mirrorlogpath to ensure no single point of failure. For your info,
Oracle only allows 10 log mirror destinations where path1, path2,
path3 etc are written to simultaneously. In case, path 1 is down,
there are still 9 to go.

2. Say I have a media failure and some or the entire
Node0000\SQL00001 directory is gone while database is up and running.
Is my only option at that moment to restore online redirect? Can I
restore a particular file instead of an online restore of the entire
database? When you do an online backup, what are backed up anyways?

What goes in the backup image is only limited by the command. Full db
backup offline or online contain exactly the same thing. Tablespace
(single or multiple) backups will contain the same thing wether online
or offline as long as they specify the same tablespaces.

If you damage the Recovery History File in the database directory
SQL00001 then it can be restored selectively from your most recent backup.
If lyou loose or damage any of the other files, you will have to restore
the full db offline and rool it forward to end og logs to recover these
files.

You cannot ever restore a full db image online. It is required to
restore always offline.
If the drive or path is so damaged that you can't restore where it cam
from the resotre command allows you to restore to a different path.

The redirect option you mention only serves to redirect or rather
relocate containers of your tablespaces.

So there is no way to have system up and running if there is a single
corrupted or missing file in my C:\DB2\NODE0000\SQL00001 and
C:\DB2\NODE0000\SQLDBDIR directories. What will actually happen when a
file goes missing. Will the system just hang or the only way to find
out a file is corrupted/missing is thru the admin notification log?

I am also curious to know what will actually happen when a log is
deleted accidently while it's still active. Will the system be brought
down?

Where can I find case study for recovery? I only find dropped table
and rollforward tablespace recovery in the info centre. There are
whole lot more things that can go wrong that need to be guard against.
HTH, Pierre.

Thanks
DB2 Convert