IBM 000-8697 ユーザーズマニュアル

IBM Informix OnLine Database Server Administrator’s Guide

With this action, the root dbspace reserved pages receive acknowledgment
that an archive has occurred. This event enables OnLine to make use of newly
added or changed resources. (A level-0 archive to /dev/null registers as a
valid archive. OnLine permits you to create a level-1 archive on a tape device
even if your only level-0 archive was created when the archive device was
/dev/null

. Because of the problems this could create if a data restore were

needed, avoid this situation.)

Having performed this function, tbtape considers the archive complete.
Synchronization with tbinit is ended. Control is returned to the
administrator.

After tbtape writes the tape header page, it begins reading and writing pages
to the archive tape in a specific order.

First, tbtape reads and archives each of the root dbspace reserved pages.

Second, tbtape reads and archives the contents of all logical log files that
contain records that are part of open transactions, up to the point of the
begin-archive checkpoint.

After selected logical log pages are archived, tbtape begins reading the
OnLine primary chunks in the order in which they are listed on the active

PAGE_PCHUNK

 page of the root dbspace reserved pages.

Mirror chunks, which are listed on the active

PAGE_MCHUNK

reserved page,

are not explicitly read for archiving. Pages within a mirror chunk are
archived only if tbtape cannot read the page from the primary chunk.