[DEMUG] Format before refreshing for backup?

[James Baranski]

For your first question, it depends on what kind of backup software  
you are using.
Some will automatically erase a backup drive on starting a full  
backup, some will not.
So I'd say that it's best to erase the backup drive if you want to  
start over.

What happens to deleted files when disk is restored is another
good question.  In theory when a backup is performed after a file has  
been deleted,
the *directory* that the file was in is backed-up, which does not  
have a pointer records
to the file that has been deleted.  So that in effect, when the  
directory is restored, the
deleted file is re-deleted.

However there are a lot of backup programs that have bugs that do  
*not* operate
correctly all the time, unless the backup and restore is performed in  
specific ways.
It's a good idea to run through tests on your backup and restore  
procedures to make
sure they perform as you expect.  The only thing worse then not doing  
a backup,
is doing backups all along, and then finding out that they are  
worthless, or tedious
to restore either specific files from a specific time, or to restore  
an entire disk accurately.
I speak from experience! *:(

Most people do either full backups, or incremental backups.  I prefer  
what I call cumulative
backups.  I do a full backup, and put it in a safe place.  I might do  
this every month, or every
quarter depending on the system.  Then each day (or week) I do a  
backup of all the files
changed since the full backup.  This way, if I have to do a restore,  
I can do it with only two
backups.  Each cumulative backup usually backs-up all the important  
files that have changed.
I could usually even do without the original full backup, by doing a  
re-install if I had too.
If the cumulative backup becomes too large to perform quickly, then  
it's time to do another
full backup, or to do backups more frequently.

Jim.


On Feb 13, 2008, at 9:21 PM, Dick Atlee wrote:

> We have a backup hard drive that has "only" a 67Gig capacity, and the
> latest attempt to do an incremental backup resulted in a "not enough
> room" message.
>
> The obvious next step (short of getting a new drive) is to clear it  
> and
> start over with a full backup.  The question is, will simply trashing
> the exiting backup meta-files be sufficient, or would reformatting be
> appropriate to avoid some kind of fragmentation or other
> read/write-slowing situation.
>
> And while I'm at it, does anyone know what happens with incremental
> backups when files are deleted between backups, and later a full
> restoration is done?  Is some record kept in an incremental backup of
> the fact that a file has disappeared (either deleted or renamed) since
> the last incremental backup, so that it will again be deleted  
> during the
> restore, or does it simply show up because at one point it was  
> backed up
> prior to deletion?
>
> Thanks for any help on this.
>
> Dick
>
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