4-36 IBM Informix OnLine Database Server Administrator’s Guide
Archive Reserved Pages
With this action, the root dbspace reserved pages receive acknowledgment
thatan 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
validarchive. 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 withtbinit is ended. Control is returned to the
administrator.
Archive Reserved PagesAftertbtape 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.
Mirrorchunks, which are listed on the active PAGE_MCHUNK reserved page,
are not explicitly read for archiving. Pages within a mirror chunk are
archived only iftbtape cannot read the page from the primary chunk.