Disaster Recovery for Linux
From SEPsesam
Disaster Recovery with a SEP sesam Recovery CD
Contents |
Supported Systems
SUSE Enterprise Server 8 and 9 (i386)
RedHat Enterprise Server 4 (i386)
Requirements
In the following description the hostname ‘recover’ represents the name of the system to be restored. The choice is freely selectable by the user, e.g. the Host names of the original systems may be selected.. The important thing to remember is that the Host Name and IP Address are properly resolved, e.g. by using DNS.
- Sesam Client Version >= 3.0.1.3
- A complete SEP sesam backup of the original system with the source “all”.
- A backup with the source disk_info
- [The SEP Recovery CD] must be able to properly recognize the System Hardware (network and harddisk). This should be verified during the boot up procedure.
Client Installation and Configuration
1. Set the new system’s CD-ROM drive as the initial Boot Device in order to begin the installation from the CD.
2. Insert the SEP supplied bootable Bare System Recovery CD in the CD-ROM Drive of the computer being restored/recovered.
3. The system will now automatically begin system recovery.
During the recovery process you will be prompted by several questions.
1. The first question asks if DHCP should be activated or not. If you are not certain select the default response - “YES”.
2. If DHCP is not active, in answer to the next question, enter the IP Address of the Computer, which is to be restored. The SEP sesam Backup Server must be able to resolve the address using either DNS or /etc/hosts.
3. In questions 3-5 you must enter Broadcast, Gateway and IP Address for this computer. In the event no DNS is available, the entry can be left open. However, the Name and the IP Address must be entered in the file /etc/hosts for the client as well as the sesam Server!
4. During the configuration the sshd service is started. You can use the following command: It is possible by using ssh root@recover and the Password sesam to log into the target or recovery computer.
ssh root@recover sesam (sesam is the password)
5. Next, the SEP sesam client will now be installed in a RAM DISK. This may take a few minutes. The network configuration should now be verified with a ‘ping’ command. Change to the system where SEP sesam resides and enter ‘ping recover'.
The configuration for the client has now been completed.
Restore the Disk Information
1. Create a new Client in the SEP sesam GUI with the name “recover” and the platform UNIX for the target system. If there is a problem with accessibility, you will need to enter an additional interface. If required this can be accomplished by accessing Components/Topology/<SEPsesam Servername>/ over the attributes of the computer in the window I/F. At this point enter the relevant data for the additional gateway (Use the Full Qualified Domain Name) e.g. backupserver.domain.de.
2. Start the SEP sesam Restore Wizard and the task of the client with source disk_info, for the computer that is being restored.
3. Choose the desired save set and activate the desired option „Full Restore“.
4. In the next Window:
- Activate the option disk_info.
At the Menu Point 'Expert', in the empty field enter -a RECOVER.
- If there is a problem receiving the Client data you must enter/select the FQDN (Fully Qualified Domain Name) in the 'Option Interface' .
- Change Target Node from <original client name> to recover
- Select „overwrite“ existing Data.
- Activate auto recover after Restore.
- For the remaining options you may use the default settings.
After these entries you may activate the Restore procedure.
| !!! Warning!!! |
|
If you answer “YES” at the next Safety Query all data on the Recovery computer will be erased/overwritten. |
After the Restore has completed the original partitions for the disk drive will be recreated. Furthermore, the partitions will be created using the command /mnt/disk. The newly created partitions should be verified by looking in the Restore Protocol or directly on the client. In the event changes to the partitions are required they should be made at this time.
Restore ALL or Complete Backup
1. Start the SEP sesam Restore Wizard and select the task with the source ‘all’
2. Select the desired save set and activate the option ‘Complete Restore’
3. In the next window:
- Change Target Node from <original client name> to recover
- Activate New Restore Target and enter the following command: /mnt/disk
- Select “overwrite existing data”
- Open the Expert session and enter “-a bootmgr” in the empty text field
- The other settings can be left at the default settings.
- Begin the restore by entering: Start
4. Wait until the restore procedure has successfully ended. You can verify that the Boot Manager has been properly installed by checking the “Restore Protocol”. If there is a problem it should be corrected on the Client before the system is rebooted. In the event the partitions or mount points have been changed these can now be adjusted in the /mnt/disk/etc/fstab.
Follow the procedure below to verify that the required Operating System Data has been restored:
- Login to the Client via ssh
- Set root privileges with sudo su -
- Using chroot /mnt/disk to activate the restored system.
If everything is correct then exit.
Finally, Reboot the System and remove the RECOVER CDROM
You should now have the original system up and running.
