Incremental - Please explain

[zoeythecat]

Hi All,

Hoping someone can help me with this dillema. Just to give you an FYI on our current backup scheme.

* Using BackupExec 8.6 for NT and 2000
* 35 GIG backup tape system
* Run Differential Mon - Thursday. Run Full on Friday
(Problem)
(1) The combined differential and Full are going over 35GIG
on one tape, so backup is failing, running out of space
on tape
(Hopeful Solution)
(1) Run Full system backup on 1 tape on Friday
(Should be 30GIG)
(2) Run Incremental Mon - Thursday

(Here is my question)
* I have been debating this with co worker. I have file selections for this backup job that will be equal to the full backup (30GIG). Now when I run the incremental the first time will it be like doing a full backup? And if so when files change will this append to the media and then run out of space again? My dilemma is if I have 2 backup schemes with 2 different tapes 1 tape will be for the full backup and the other tape will be for the incremental. Will I be in danger of running out of space on both tapes and reaching the 35GIG limit?

Hope this is not confusing and appreciate any help or advise on the best backup solution for me.

TIA,
Zoey

 

[Qdog]

An incremental backup, is a backup of all files that were modified or created since the last normal or incremental backup. With this method, the archive bit is reset so the files will appear to the system as having been backed up. For example if a job is scheduled for a full backup on Monday at 0400hrs (which completes at 0600hrs) and an incremental backup at the same time each day (which completes at 0500hrs) on Tuesday through Thursday, each day's incremental backup will only backup those files that have been changed or created since completion of the last normal backup at 0600hrs or the last incremental backup at 0500hrs of the day in question.

 

[Zelandakh]

I'd do a Friday job as a full backup, overwrite.

Then do a Midweek job as an incremental using a Midweek tape.

This keeps the jobs on separate tapes, solves the problems.

Change the Friday tape every 20 uses as good tapes are critical...

 

[blonde]

I do my full backups on Wednesday. reason being that alot of the holidays have either Friday or Monday off. then I would follow with the incrementals. Keep in mind if you have to do a restore of a directory, it would be from the last full and then each incremental after that. but The fulls I do on Wednesday, so if I need to change a tape, I am here ..blonde

 

[zoeythecat]

Thanks for all your replies. This puts it into perspective for me. The scheme we decided on was this:

(1) We will use 2 tapes, but 1 job will utilize both tapes.

(2) 1 tape will be used for Full backup on Wednesdays

(3) 2nd tape will be used for Differential for:
Thurs + Friday + Monday + Tuesday.

Thanks again.

 

[blonde]

GOOD job. I was re-reading my input to you. I do fulls on Wednesday, and then Differentials on mon-tues-thurs-friday. If you do a restore of a directory, would be the last full job, and then the last differential that you would have to restore from...Blonde