Backup Types

[sdabreo]

Dear All

I have hp dlt drive, and I am using win2k3 inbuilt backup utility to take my daily backups. As of now my backup option is normal and i am taking backup of only selective folder everyday. If somebody by mistake deleting folder / files in server only the existing folder or files will be taken as backup and I am not in a position to retrieve from earlier backup.

Tried to configure differential backup, but while checking the tape after backup, only the folder name reflecting no files were present inside tape also files are not backed up.

I am confused, what backup method i should use, if i am doing differential backup how exactly it's going to work.

Kindly help me..

 

[jfwebber]

Here are the types of backups you can do:

Daily

Backs up files that have changed since the last daily backup. If a file is modified on the same day as the backup, it will be backed up. The archive attribute of the files is not changed.

Incremental

Backs up files that have changed since the most recent full (normal) or incremental backup. If the archive attribute is present then it means the file has been modified – only files with this attribute are backed up. Once the file has been backed up, the archive attribute is cleared and only set once the data has been modified again.

Full (Normal)

Backs up all files that have been selected, despite the archive attribute setting. Once the file has been backed up, the archive attribute is cleared until the file is modified. When the archive attribute is set again, it indicates that the file needs to be backed up.

Differential

Backs up files that have changed since the last Full backup. If the archive attribute is present, it means that the data has been modified and files having this attribute set will be backed up. However, in this case the attribute is not cleared so as to allow other types of backups to take place on this data at a later stage.

Copy

Backs up all files that have been selected, despite the archive attribute setting. The archive attribute is not changed, so that other types of backup can be performed on the same data.

Hope this helps.

Jim W MCSE CCNA
Network Manager

 

[sdabreo]

In my case, which one will suit, should i have combination of normal as well differential backups? I am using win2k3 backup utility, i tried before normal backup is taking the backup of everything, but in differential backup job only folder name are displaying and no files were taken backup.

In differential backup newly created files will not be taken backup? That should be taken care in normal backup?

How the archieve bit is set? Is't automatic??? OS dependend?

Kindly help me

 

[karlisi]

Archive bit is set by OS when someone (including system) edits file/folder.

Try to modify some files after normal backup, and then make differential backup, you should see these modified files backed up.

===
Karlis
ECDL; MCSA

 

[kmcferrin]

http://en.wikipedia.org/wiki/Archive_bit

That's a good enough explanation.

Full backup will backup all files regardless of how the archive bit is set, then it will clear the archive bit on all files.

Incremental backup will backup all files on which the archive bit is set, i.e., the file has been changed since the last backup. Then it usually clears the archive bit.

Differential backup will backup all files on which the archive bit is set, i.e., the file has been changed since the last full backup, but it does not usually clear the archive bit.

If your backup method is Full + Incrementals, then in order to do a full restore you will need the media that has the most recent full backups on them plus the media used for all of the incrementals that have been done since then. You would do a restore of the full backup, and then a restore for each incremental backup until you get to the most recently backed up state.

If your backup method is Full + Differentials, then in order to do a full restore you will need the media that has the most recent full backups on them plus the media that has the most recent differential backup on them. You would do a restore of the full backup and then a restore for the single, most current, differential backup.

The biggest differences are:

1. Full-only backups allow the shortest restore times, but take the most amount of time to do the backups and eats up the most amount of backup storage space.

2. Incremental backups make for the longest restore times (usually), but take the least amount of time to do the backups and eats up the least amount of backup storage space.

3. Differential backups make for a relatively short restore time, but as time goes by the backups times usually get increasingly longer and the amount of backup storage space required for each backup gets increasingly larger.