The aim here is to
describe a Linux System Recovery using Linux Live-CD and Symantec Netbackup Backup.
Before delving into technical details, we want to highlight the fact that
Symantec Netbackup has a Bare Metal Recovery features that suit this type of
Recovery. But this feature doesn’t support all Linux OS (most of the popular
ones are supported). For instance, this procedure was used to restored a
complete Redhat 9 :) Installation (it can also be used for a P2V migration).
Let’s check what is required for such restoration.
1. A valid Full Symantec Netbackup Backup of the system we're trying to restore(I guess
that one is obvious)
2. A Linux Live CD that can support Symantec Netbackup
Client, we’re using Ubuntu 8.04 LTS in
this guide (fully supported, a list of supported OS can be found here)
3. The installation CD of the Distribution
we’re restoring, as stated above, we’re
restoring a Redhat 9. So a Redhat 9 Boot CD is what we need for this case. The
main reason for having the Install CD of the distribution is to avoid some
incompatibility (like creating a filesystem which isn’t supported by the
maintenance tools –e.g fsck- of the restored system)
4. An
Internet Connection (though it isn’t mandatory, we may just need some softwares/packages
to install before installing Symantec Netbackup Client)
Once these prerequisites
are met, we’re ready to start our restoration. As already described above,
for this post, we’re using Ubuntu 8.04 LTS as Live-CD and are restoring a Redhat 9
Installation (the procedure can be easily adapted to others Distribution).
Below, a step-by-step (from a to f) description
a.
Boot on the Redhat 9 CD in rescue mode (linux rescue at the prompt) and recreate
the target filesystems (the ones which will contain the restored data). Below
is what we’ll create during this step.
MountPoint
|
Size
|
Filesystem
|
Device
|
/
|
65 GB
|
Ext3
|
/dev/sda3
|
/boot
|
100 MB
|
Ext3
|
/dev/sda1
|
/var
|
65 GB
|
Ext3
|
/dev/sda2
|
Swap
|
10 GB
|
Swap
|
/dev/sda5
|
Note
that the target filesystems could be re-sized during this step (as long as we give enough space for the
restoration). It’s also important to create these filesystems using the operating system we’re going to restore (avoid some filesystems features incompatibilities).
We
just need a shell at this stage, so we’ll choose skip during the step in the
screenshot below.
The
filesystems are then created using fdisk and mkfs.ext3, mkswap… (as usual)
b.
Reboot the system on the Ubuntu Live-CD
and install the required software for Netbackup Client Installation.
I
assume that the network connectivity for Internet Connection and Software
Installation is done for the Ubuntu LiveCD System. The list of software required to
install on Netbackup Client for Supported Ubuntu/Debian can be found here.
For proper NetBackup client operation on Ubuntu 8.04 Server Edition (64bit) the
following packages are needed:
- ia32-libs (In Universe Repository, so
universe repository was enabled)
- xinetd
- ssh-server/rsh-server (required for
remote install only)
We’ve
also added the following for our specific environment
- nfs-common (required to mount the
directory where we’re keeping Netbackup Client binaries)
- autofs (use to automatically mount
the NFS shares)
Let’s
also configured autofs to use /net automount features and complete Netbackup Client Installation.
c.
After the prerequisites, we’re adding
Netbackup servers entries to the /etc/hosts files, add the Ubuntu Client
Entries in Netbackup Servers hosts file, Install the client and register the
Ubuntu LiveCD node.
On Ubuntu LiveCD,
On
Master/Media Netbackup Servers,
d.
We can now mount the filesystems that were
previously created (step a.) in the directory where we’ll push the restoration
e.
Let’s the restoration begin (using
Netbackup Java Console, specifying as source the system to restore and as
destination our Ubuntu Server, choose “restore everything to different
location” and fill with the name of the directory where / is mounted)
Choose
the last full you want to recover from the backup history and start the /
restoration.
Uncheck the rename soft/hard link options that are
enabled by default.
f.
After the restoration, we can reboot the
system and fix the Specific Operating Systems Issues that will arise. In this
case, we’ve to do the following:
1. Reinstall
the Grub, for that we’re going through the “linux
rescue” using Redhat 9 CD. We’ll let the rescue mode trying to mount
the restored system under /mnt/sysimage. If not able, mount the filesystem
manually and chroot under the mounted directory
2. Modify
the /etc/modules.conf to add Vmware scsi controller driver by replacing the
following in /etc/modules.conf
# alias scsi_hostadapter mptbase
# alias scsi_hostadapter1 mptscsih
3. Recreate
the initrd which will now have the correct scsi
modules
4. I
found that my etc/fstab was set to use e2label , so label were well reassigned
to each filesystem