2014 Differential Backup Problems / Question

The short answer heree is:
The controls for the type of backup is determined by the user selection of what is included within the backup scheme.
Perhaps yours is set to do a full after 4 diff.

The response needs to be in more detail. Too many diff is not a good thing as to much dependance is placed on the old full backup. Your best backup procedure is for your full always to be reasonably current.

Look at link 2, illustration 11-Diff for one example of how to control the use of Dif files using automatic cleanup.

I appreciate the input..
Per your suggestion I did check your "amazingly detail instructions" and compared the settings on my system...

For both drives C: & D: the settings are set the same...
1. Checked: Create only differential versions after the initial full version.
2. NOT Checked: Create a full version after every (5) differential versions.

D: Drive has files of the following format:
D_20140119_full_b3_s1_v1.tib (72 of these files _v1 thru _v72) I split my backups at 4,550,816 kb size
and diff files like:
D_20140119_diff_b3_s2_v1.tib (five of these files _v1 thru _v5)

C: Drive has files of the following format:
C_20140119_full_b2_s1_v1.tib (56 of these files _v1 thru _v56) I split my backups at 4,550,816 kb size
and another set of file (that should have been "diff" files but look like this
C_20140119_full_b2_s1_v1-2.tib (55 of these files _v1 thru _v55) that's right there is one less file in this group...

you can see on the D: file designations the diff does go from b3_s1 to b3_s2...
but on the C: it stayed b2_s1 under both runs and added the -2 at the end of the file name...

it would appear that some other setting is affecting the "full" vs "diff" and influencing the file naming convention

Any input is muchly appreciated...
Thanks in advance...
Ed

I am not sure what question your last post is asking.
The task with the extra -1 and -2 was caused by some type change. either an edit or a restore would cause such.
The program had what it thought was an existing backup name and added the -1 to make it a different one.

1. Checked: Create only differential versions after the initial full version.

As I wrote in my guide, I avoid the default backup scheme and prefer the custom so I have control over my backups to include automatic cleanup.

The "Create only differential versions after the initial full version" creates too many backups dependant upon the original. At some point in the future, the user will be forced to do manual cleanup or manual deletion in order to control the overall storage size. For myself, I want more frequent full backups. I also totally avoid any consolidation settings as being risky to my data plus I make no changes to my task configuration. If and when a restore is needed, I stop using the current tasks and begin a new set of tasks pointing to a new storage folder with no intermixing of tasks. These are some of the rules I practice and some differ from the program such as task editing is permitted and the default setting does exist and consolidation is an offered setting but all three I totally avoid as being too risky for my data.

The below is an extract from link 2, illustration 11-Dif

Figure 11-Dif: -Example of custom/differential backup method settings

If using differential type backups (which is full + X Diff), the 11-Diff illustration is my recommended method. Change the 6 or 4 to fit your available storage.
These automatic cleanup settings will provide for automatic deletion of the oldest backups after the "Store no more than X number of chains" quota has been reached.
In this example, deletion of oldest backup chain will occur immediately following creation of backup #29.

Allow space for 1 more full backup in addition to "Store no more than X number of chains" as the program will NOT delete the oldest full until its replacement has been successfully created.

In this example, one chain or one recent version chain =1 full plus 6 diff or 7 files per chain.
If keeping 4 recent version chains (4 chains of 7 each) retention would be 28 files. Deletion begins after backup 29.

When restoring, a single diff file is selected and that specific diff plus its full backup base will be restored (2 files restored).