IBM 000-8697 Archive Types Level-1 Archive, Level-2 Archive, Incremental Archive Strategy

Operating OnLine 3-45
Archive Types
Level-1 Archive
Alevel-1archive contains a copy of every disk page that has changed since the
lastlevel-0 archive. All disk page copies on the tape reflect the contents of the
disk pages at the time the level-1 archive began.
Level-2 Archive
Alevel-2archive contains a copy of every disk page that has changed since the
lastlevel-0 or level-1 archive, whichever is most recent. All disk page copies
onthe tape reflect the contents of the disk pages at the time the level-2 archive
began.
Incremental Archive Strategy
Figure3-2 illustrates an incremental archiving strategy. Each of the archive
levels is defined as follows:
■Level-0 archive is created once every nine days.
■Level-1 archive is created once every three days.
■Level-2 archive is created once a day.
Figure3-2
Incremental archive example
Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu
0 0
1 1
2 2 2 2 2 2 2