Create a backup of centos 5 server

[billmckinstry]

Hi, Have been playing with Centos 5 and finally got it installed and have done most of the updates.

Before I proceed much further it would be nice if I could create a backup/install disc of how it is now. No Data, just the setup and software used etc.
Have a dvd rw on the server.

I recall mondo rescue installed years ago on a linux server we used.

Appreciate some advice. Regards, Bill

[reed9]

Hello,

There are a number of options.

Clonezilla

HowTos/BackupPC - CentOS Wiki

Bacula, the Open Source, Enterprise ready, Network Backup Tool for Linux, Unix, and Windows
Factual Matters: Install Bacula on Centos 5

[oz]

A few others that can do this:

FSArchiver, Ghost4Linux, and PartImage, or you could use the dd command if you wish.

[billmckinstry]

Tks Reed9 & Ozar, plenty of options available to study

[Rubberman]

Myself, I use an external drive and make a bit-image backup of the system drive (including partition table and boot-loader) to a file on the external drive. I boot from a recovery/live CD/DVD or USB thumb drive first, so the file systems are not mounted. You can use either the 'cat' or 'dd' command to make the actual copy. 'dd' is preferable as you can specify a more optimal block count for each read in order to maximize your disc I/O.

[billmckinstry]

Could I backup onto a network windows xp pc?

[Rubberman]

Could I backup onto a network windows xp pc?

Assuming that your windows pc has enough disc space and that the live CD/DVD/USB boot device uses a kernel with CIFS support (most current ones not intended for embedded systems do), then you can mount the remote file system and use that for the output of the cat or dd command. Remember, you are going to create a single file which is an image of your disc. Example (assumes 192.168.1.100 is IPv4 address of windows pc):

mkdir /mnt/winpc
mount -t cifs //192.168.1.100/shared-dir /mnt/winpc
dd if=/dev/sda of=/mnt/winpc/linux-image-name
sync
umount /mnt/winpc

You now will have a file on the windows pc that is an exact image of your linux hard drive. Some caveats:
1. Make sure your windows pc shared directory is on an NTFS volume. A FAT or FAT32 file system can only support files less than 4GB in size.
2. The sync command is to make sure that all data from the copy that is in local file system cache has been written to the windows file.
3. The umount command disconnects from Windows so it will know to properly clean up.
4. The image, if you don't compress it, will be the actual physical size of your Linux hard drive. If you want to compress the data before it hits the windows pc file system, then do this instead:

mkdir /mnt/winpc
mount -t cifs //192.168.1.100/shared-dir /mnt/winpc
dd if=/dev/sda | gzip -c >/mnt/winpc/linux-image-name.gz
sync
umount /mnt/winpc

I am using gzip instead of the better compression of bzip2 due to the tremendous difference in speed between the two. Gzip compresses quite well, and is probably an order of magnitude faster than bzip2, so that's what I generally use, being the impatient sort of fellow!

[billmckinstry]

Thanks again Rubberman,

Just checked our current mailserver and df -h shows files total <1.5gb.

Just a mail server.

When, if we ever, we go back to a full file server we may not grow much as the data will be on 2 other hdd's in the server that can back each other up.

This backup issue should just be the installation for avoiding repeating downloads should a new install be required.
Am I correct ?

[Rubberman]

Thanks again Rubberman,

Just checked our current mailserver and df -h shows files total <1.5gb.

Just a mail server.

When, if we ever, we go back to a full file server we may not grow much as the data will be on 2 other hdd's in the server that can back each other up.

This backup issue should just be the installation for avoiding repeating downloads should a new install be required.
Am I correct ?

Essentially. That's what I do. I keep the system disc backed up to an external drive to restore system software to a known good point should something "go south for the winter", and backup data separately so I can restore operational data separately if needed. I also keep operational data (such as /home) on a separate drive so system restoration is as fast as I can make it. In fact, if you have a removable system drive (I do), you can keep a live copy of the OS on the backup drive and recovery is a simple matter of shutting down the system, removing boot drive, plugging in the new drive, and restarting the system. A max of 5 minutes at worst to restore the system to operation.