How to backup and restore Alternate Pathing databases

Asset ID:	1-72-1003031.1
Update Date:	2010-12-13
Keywords:

Solution Type Problem Resolution Sure

Solution 1003031.1 : How to backup and restore Alternate Pathing databases

Related Items


Sun Enterprise 10000 Server

Related Categories


GCS>Sun Microsystems>Servers>High-End Servers

PreviouslyPublishedAs
204151

Symptoms
When creating backup tapes for a full system disaster recovery on
a machine that has Alternate Pathing (AP) installed, it is not clear how
the AP databases can be backed up and recovered, as they reside on raw
disk slices.

There will be multiple copies (at least 3) of the databases.
Each one is unique and must be copied back to its original slice
upon the restore. This is because each database holds data about its own
location and the locations of all other copies.

Resolution
The following is a tested procedure that can be used to backup and restore the AP databases.

Procedure

Create the off-site disaster recovery backups. (at regular intervals)

- Shutdown applications and unmount all disks except the boot disk.

- Create a directory on the boot disk: /backup

- In the /backup directory, make copies of /etc/vfstab, /etc/system, VTOCs of all disk etc.
Output of apconfig -D (database layout)
Output of apconfig -S and -N (disk and network setup)
Print out hard copies as well.

- Copy each AP data base into a file in this directory using dd.

Each database is different, even when they are in sync, as they contain info about which slice they are in, and
each one must be copied back to its original location.

Example:

 cd /backup
dd if=/dev/rdsk/c0t0d0s4 of=apdb-c0t0d0s4

GOTCHA ALERT: Don't use any slice 0 for apdb's and don't use huge slices!

- If there are AP network devices, rename the hostname.XX to be a real active interface.

Example:

 mv hostname.mqe0 hostname.qe0

- Take the boot disk out of AP using the "apboot" command. This modifies the /etc/system file and the vfstab (even takes care of swap)

- Reboot (to be sure you can).

- Shutdown to single user.

- Backup all the file systems with a level 0 ufsdump.

- When finished, boot up to multi-user.

- Run apboot to AP the boot disk again.

- Move back hostname.xxx files.

- Uncomment the vfstab.

- Reboot.

Recovery

- Perform the ufsrestores.

AP recovery

- copy back the apdb's to their proper location.

Example:

 cd /backup
dd if=apdb-c0t0d0s4 of=/dev/rdsk/c0t0d0s4

- reboot

- Check all is OK with acponfig -D etc.

- Move back hostname.xxx files.

- Uncomment the vfstab.

- Reboot.

If it all goes horribly wrong the system should be usable without AP; just edit the vfstab is so that real devices are mounted.
Then, AP can be set up again from scratch.

The disks that are being restored to must be identical in geometry to the originals for this procedure to work. If the disk are not identical then AP must be set up again from scratch after the recovery.

Product
Alternate Pathing 2.3
Sun Enterprise 10000 Server

alternate, pathing
Previously Published As
18060

Change History
Date: 2006-01-18
User Name: 95826
Action: Update Canceled
Comment: *** Restored Published Content *** SSH AUDIT
Version: 0
Date: 2006-01-18
User Name: 95826
Action: Update Started
Comment: SSH AUDIT
Version: 0
Date: 2004-10-19
User Name: 7058
Action: Approved
Comment: Reformatted the document using STM. It had a weird layout with 'o' for bullets.
Made a few minor punctuation/grammar fixes.
OK to publish.
Version: 3
Date: 2004-10-19
User Name: 7058
Action: Accept
Comment:
Version: 0
Product_uuid
a4216722-2bd5-11d6-8a95-deca186ffb2f|Alternate Pathing 2.3
29ddef46-0a18-11d6-92de-ae47474f0f6c|Sun Enterprise 10000 Server

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