Running out of space - delete some differential backups? (TIH 2011)
Hi,
I'm using the differential backup method. Now my 500GB HDD is running out of space. Is it possible to delete some differetial backup files between the first full backup and the last differential backup? The attachment shows the archive structure.
Every backup archive consists of one full backup (f.e. System_(0).tib) and five diff backup files (System_(0)2.tib to System_(0)6.tib). Then followed by the next full backup System_(1).tib and five diff backups and so on. Which of these files can be deleted without causing any trouble in case of a restore?
Pat L offers good advice and I cannot disagree. However, TrueImage does provide a means of doing this--but do it at your own risk. As you have multiple chains, the risk should be related only to the chain(s) you would be working on.
You appear to have 6 full backups. If you accept the default setting of normal compression, the backup size will normally be about 60-70% of your used space. Bad disk sectors can also cause a more data to be included in your backup. As for your question about why one is so large or too small, how does it compare to the 60-70% rule. Also, is it possible that the larger backup also included a prior TI or Windows type backup?
You appear to be able to delete all of your older differentials
(0)2 to (0)6
(1)2 to (1)6
The file which is 321,047 KB is suspect based on its size. You may want to validate.
In General to delete unwanted differentials:
Open the TI program under the My Backups header, dbl click on the Task name which is creating your backups.
The resulting screen should list most or all of your backups starting with the oldest along the bottom left side. If you hover your mouse over each of squares, the info about the backup (type-size-date) should identify information about the backup.
If you identify a differentials that you want to delete, then RIGHT click on that specific timeslice button and click on the "Delete version" option. Repeat the delete option for any other differentials of the same chain you wish to delete. Upon completion of the deletion of the differentials for the first chain to be deleted, then again Right Click on the remaining files in that specific chain and choose the "Validate" option. You may have to provide pointers to the program but not sure how your program will react.
Assuming that the remaining files for that chain will validate, after the validation completes you can delete more chains.
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Another possibility but not according to TrueImage instructions.
a. Open Windows Explorer and delete differential backups (0)2 to (0)6 (assuming that you know they are old differentials)
b. Open TrueImage and "Browse for Backup" option and browse to the System-(0).tib file and choose the "add to backup list".
c. Once the system-(0).tib file is part of the task, then choose the validate option to validate the backup.
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In the recent past, the deletion of differential backup would prevent the file from passing validation but the file would till restore. In the current 6696 version, both methods above appear to validate with equal success after the deletion of parts of the differential chain.
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Be reminded of the potential risks of deleting backups. The automatic cleanup of keeping x number of backups (as suggested by Pat L) has been quite successful--when starting as a new task with a new target folder and a new target name. I make it a practice of including two underscores as the last two characters in target backup file name.
The type of backup that offers the most restore options with the least hassle is the backup which includes all partitions. If running Windows 7, a backup of only the system C partition is usually not sufficient data to restore to a new replacement disk.
Some sample settings of automatic cleanup. Use your own number of chains,etc. The keep x number of chains seems to have better success than the keep x number of days or keep x amount of space.
Hi GroverH
The type of backup that offers the most restore options with the least hassle is the backup which includes all partitions. If running Windows 7, a backup of only the system C partition is usually not sufficient data to restore to a new replacement disk.
Why do you say this? I have restored just the "C" partition for W7-64 and have no issues with the running OS after restoration. What problems do you see or feel can happen.
As the paragraph includes, my point related to restoration to a new replacement disk. There are usually no issues when restoring the C backup overtop an existing install. The problem comes when the trying to move to a new disk.
Many of the Window 7 installations include a "system reserved" or a boot partition and/or vendor recovery partition and these are separate from the C partition. If the 'system reserved" partition exists on the original system and it is not restored, then the system will probably not boot when first started following a restore. The user will need to either restore the "system reserved" or the boot partition from another backup(if such a backup was created); or use the Windows installation disk (which many do not have) and use the install CD to do a repair of the installation.
If your Windows 7 install was an upgrade from a prior version, then there is a good chance your C partition may be your active and boot partition, thus a backup of C may include what you need. However, most new Windows 7 retail computers does have multiple partitions so to be safe, I recommend that the best backup is a backup that includes all partitions. Many users are not aware of how their disk is partitioned (Windows Disk Management graphical view) so a full disk backup offers the best protection for them as well.
Hi GroverH
Yes Agree - but that was not 100% clear in the original post :-)
Hi Ray,
Yes, your point is well taken. The problem is that the post #2 is much too long already so the question becomes where do you stop. This varies with each situation but most often is a question of time. Thanks for calling this to my attention.
Grover
This image of sample settings for automatic cleanup is fabulously useful. I wonder if you could possibly discuss the pros and cons of the numbers in "Create a full version after every [n] differential versions" and "Store no more than [n] recent version chains"? I would like to understand a bit more the consequences of the numbers. What does it mean to choose 6 for the first and 4 for the second, as you have in your example?
Thank you so very much,
TG
A chain is made of a full + Y partials.
The first setting sets the number Y of partials in the chain.
The second setting X (keep most recent chains) sets the number of chains that ATI will keep.
ATI will always first complete a new full before delete any older chain.
The first consideration is backup space.
As a consequence you need enough space for (X+1) fulls plus X*Y partials.
The second consideration is backup reliability.
My rule of thumb is that the last full validated backup should never become so old that you would not consider reverting back to it. The idea here is that backup files can become corrupted or damaged. Validation helps detect that. In my settings, I arrange for each chain to be validated once before a new full is created.
The last consideration is ATI reliability.
From experience, the keep most X recent chains settings is the most reliable, straightforward to understand. Changing the X value after the backup is started can lead to unexpected results (longer chains than anticipated) but tend to sort themselves out after the next full is created. In general, it is better to create a new chain when the backup name, scheme, retention rules or destination is changed.
In response to your question TG, It really comes down to
how frequently you need backups created. and
how much time can be expended in backup creation and
how important is the data and
how much storage space do you have.
The illustration above was in answer to a specific question.
The 6 is the number of short term backups (incremental or differential type) that will be created before the next FULL backup. It was a selection mostly based on a full being performed once weekly and daily incrementals with a repeat of a new full each week. But the schedule could be other than daily. A backup completion of this group creates one "recent version chain." Understand some people choose to FULL backups only while others do full plus x number of increments or full plus x number of differentials. In my example above, x=6.
The 4 was the number of backup chains. Storage space is the issue here. This figure can be adjusted to more or less based on your needs. More is better than less as you want to retain as many backups as space permits.
Examine link #2 in my signature below and look at illustrations figure 11-Full; and 11-Inc; and 11-Diff (which is shown in prior post above).
I believe you would also find this helpful.
http://forum.acronis.com/forum/38799#comment-122496
Grover,
Thank you so very much for your detailed and clearly stated/diagrammed replies. You have made it clear enough to me that I can move forward and make informed decisions. It's an absolute pleasure to read your descriptions. Thank you so much for putting in the time to explicate the concepts and algorithms step by step. Would that the user's guide were written so clearly.
You deserve a big round of applause for your contributions on this forum.
BRAVO! THANKS!
TG
Thanks you TG. I'm glad it was helpful. All of us must go through a learning stage.