Backup Media

The number of servers and size of your data dictates your backup media
Backups onto floppy — good for Full backups of /etc
Backups onto Zip — good for backups of 200Mb
Backups onto CDR — good for backups of 600Mb
Backups onto DVD — good for backups of 4GbMb
Backups onto Tapes — good for backups of up to 40-80Gb, and more with tape libraries
Backups onto Disks — good for 500Gb — xxTeraByte Raid5 Backups

NEVER backup your data to the same partition, nor same disk
if you lose the disk…you do NOT have any backups

Backups are best done to a DIFFERENT server
protect your backups from hardware flakyness and random power surges etc

Tape and CDR backup media REQUIRES you to change it daily/weekly…
if you forget, you lose the previous backup… and you may also lose todays incremental backup data too
You have to clean the tape head regularly
You can lose one of the daily incremental tapes, or someone can walk out with your corp data
Restoring a file from tape can be a slow process ( hours and hours )

One 20Gb can hold about 1-2 months of full and incremental backup of another 20Gb disks depending on data amd backup methodology

Backup Failures
Backup Failure Modes

Test Your Backup Methodology
Test your backup methodology before you need it restore/recover from a catastrophe
Rebuild a new server with its data restored from backup only
Pull the plug on the “main system” being backed up

Check that your backups files contain all your directories you wanted
Check that your incremental backups files are created daily
Check that your full backup disks have enough space left for this coming full backup

Offsite Backup Methodology
In the Old days..
There was typically only ONE building with all the mainframe computers
Only one copy of all the 9-track tapes and removable 14″ hard disk platters
Tapes was cheap, while memory, disks and computers were extremely expensive

In todays market..
Most corporation have multiple buildings and PCs on each desk
Corporate computer data is spread across the street and across the country and around the world

Store Bldg_1 computer data in the OTHER building via your private VPN connection
Office backups is still good for archives for the attorneys to review and stake their claims

[ OLD ] Purpose of offsite backup
In case of fire, earthquake, you’d have your important data stored safely and securely offsite
You have an offsite archive of progress made on the projects

Problem with offsite backups
They have access to your passwd info
They have access to all your confidential material
It might take days/weeks/months to find or restore out-of-date data from offsite tapes

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