Solved How Many Increments?

[seekermeister]

I understand that this board was designed for Windows backup discussions, but it still appears to be the most appropriate place for this topic. In the past, I always made regular full backups manually, but in early January, I decided to try the incremental method with TI 2012. I have never attempted to recover the system with those increments, but as far as I can tell, it appears that they were all successful.

The question in my mind now, is how long should one continue incrementing a particular image...indefinitely, or would it be wiser to start over periodically? If the latter, how many increments between full images?

 

[wanchoo]

I suppose one can go on incrementnng indefinitely.

However if one of the incremental files gets corrupted for any reason then all the incremental backups done after that shall stop to function. Therefore depending on how frequently you do an incremental backup I think their number should be limited between 5 and 10.

 

[whs]

The problem with incremental is that when you lose one increment in the chain, you lose the whole set. Differentials do not have that problem and would be my second choice (first choice are full images).

I would suggest you make a new base after 5 or 6 increments, and keep at least 3 sets (grandfather approach).

 

[wanchoo]

After one has begun on a new base, all the earlier increments can be safely deleted to save disk space.

The problem with incremental is that when you lose one increment in the chain, you lose the whole set. Differentials do not have that problem and would be my second choice (first choice are full images).

I would suggest you make a new base after 5 or 6 increments, and keep at least 3 sets (grandfather approach).

 

[whs]

After one has begun on a new base, all the earlier increments can be safely deleted to save disk space.

The problem with incremental is that when you lose one increment in the chain, you lose the whole set. Differentials do not have that problem and would be my second choice (first choice are full images).

I would suggest you make a new base after 5 or 6 increments, and keep at least 3 sets (grandfather approach).

That depends. It is a timing problem. The previous base may not be the one you want. And disk space should really be no problem these days where most people have acres of it.

 

[Brink]

Hello Seekermeister,

When you create a Windows backup (scheduled or not) through "Backup and Restore", they will be incremental backups. You will be able to create as many as you like until you run out of the max space (see Option Two at link) that is set to be used for backups at that location. When you run out of space, Windows will automatically start deleting the oldest "Backup File" in the "Backup Set" (incremental) to make room for the newest incremental backup, and update the entire incremental backup so as not to lost the whole thing as Wolfgang described above.

I think creating new differential backups each time would be better if you have the HDD space for them. This way you could delete one without wiping out the whole backup since each one is it's own whole backup. If you like the tutorial below can show you how to have a shortcut to use to create new differential backups each time instead of incremental ones through Backup and Restore.

http://www.sevenforums.com/tutorials/203196-backup-make-create-new-backup-shortcut.html

Hope this helps.

 

[Wishmaster]

I would go with Differential over Incremental as well, since a differential anywhere in the chain is stand alone, in the sense it only needs the last Full image.
Where-as Incrementals rely on every piece of the chain.

It would be a good idea to do a full backup periodically, although I must admit Ive not had any issues restoring from a differntial any where in the chain.

Couple ways you could go about it:

You can either have the differential continue on a schedule, and clean up after itself deleting some that are a certain age or however you want.
But, have a second Schedule that just does Full Images, say every 2 weeks or once a month.
this way you always have something to fall back on in case the Differential fails.

Or you can do something along the line of .. Start a New Differential chain after 6 differentials.
Basically, a new Full Image weekly, and daily differentials. Maybe keep the last 4-8 chains.
This would be my prefered method.

 

[kado897]

Differentials are the way to go. I do one full image a week and a differential every day. I keep three sets of backups.

Incrementals will generally be faster than differentials but as stated above If you lose one then any later ones are useless. Not only that but restoring from a long incremental chain can take forever as it restores the base first and then applies each incremental in the chain sequentially.

 

[seekermeister]

I'm still mulling this around, but the posts have just about convinced me to change over to a differential scheme. The part that is unclear is if I do so, how many differential images to keep? Since each differential image only requires the initial full image, and stand alone from previous differential images, I don't see much need for those previous differential images to be kept. I suppose it is possible that an image could become corrupted after it was created, but the only way I can think of is if the storage drive develops bad sectors. The drive could fail in other ways, but if so, that would probably effect all of the images anyway.

 

[kado897]

You should do full images as often as you would if you were not doing differentials. Regard taking differentials as a bonus to allow you to have a more recent backup if anything goes wrong.

 

[Wishmaster]

How many is ultimately up to you, as you know better than we how often and how critcal the backed up data is. Or rather, if a restiore was needed how far back you could go without loosing much.

But look at it this way.
So long as you have the host Full Image, any differential is just as good as a full back up, only smaller.

Lets say you do the Full Image, and 6 differentials, then start a new chain. Thats equal to a full backup daily.
But, with the differentials you could go back and delete certain ones. Say, keep the Full backup, and every other diff. and it would not hurt a restore.

You can literally keep as many as you want. Its really going to be more about how many you need.
The other good thing, provided backup space isnt a issue, is that with ATI2012 youll be able to restore single files with the right click context menu that will include versions in each diff, across all chains.

I never thought much about it untill I accidently overwrote some game saves I didnt mean to. and didnt immediately realize I had.
It saved me by just restoring that 1 save file to a previous version 3 days prior.
So while sometimes it may seem to much, if something changes often, its a good idea to have several versions back.

 

[seekermeister]

Thanks to everyone. Some might say that one right answer is sufficient, but I always prefer to hear it from multiple sources.