Windows Server Backup to keep a copy number problem

Configure Windows Server Backup when you can configure a backup point in time and backup storage location, but the number can not be configured to retain backups. As a basic backup tools provided by Microsoft, do a simple backup or can. But for the same backup task, after repeated backups, the number of copies to keep, this is not a change that. For example, there are four copies of the backup for recovery.

wbadmin command you can specify the number of reserved copies, deletes redundant. For example: wbadmin delete backup -keepversions: 50

but still can not keep a copy of the pre-specified number.

Backup uses VSS. As for exactly how many copies can be stored, VSS is dependent on disk space that can be used, but not the total number of space on the disk. This can vssadmin list shadowstorage to see. Example, I used to put the F disk backup default VSS is not limited in the use of space, and are currently using 610MB.

You can use commands to adjust the disk space used by VSS, vssadmin resize shadowstorage / for = f : / on = f: / maxsize = 320MB

note that the use of this space needs at least 320MB, at least 1MB can not. Adjust space, will lead to the disappearance of a copy immediately before, VSS use of space is cleared. The result is like Ituri situation, backed up several times, but only one copy available.
https://www.cnblogs.com/qishine/p/12106487.html


can adjust the amount of disk usage VSS through a graphical interface, this will not clear the original backup copy.