I try to clarify this a bit more ...
After restoring the snapshot, you have an "image" of the data
exactly as it was while the server was blocked when taking
the snapshot. The command "onmode -c block" explicitly
writes a checkpoint so that all data will be on disk and the
disks will be physically consistent. Only after that will the
command "onmode -c block" return the prompt to the user.
However, this physical consistency does not mean that things
are logically consistent, i.e. regarding transactions, etc.
Because of this restoring the snapshot actually corresponds
to a physical only restore of the dbspaces.
After a physical only restore, a logical restore should follow
to make things logically consistent. This is the logical restore phase.
The minimum work required to be done in general is to roll back
any open transactions. This needs to be done even if there are
no logs to restore. If there are logs to restore, log records in them
can be rolled forward starting at the point of the block checkpoint
While restoring the snapshot with external means corresponds to
the physical restore phase, ON-Bar or ontape is used to
accomplish the logical restore phase.
I hope this makes things somewhat clearer.
BTW: you may want to consider also saving some files in directory
$INFORMIXDIR/etc/ at the same time when you are doing the
snapshot (i.e. as part of the snapshot, e.g. .../etc/oncfg* file).
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XXXX@XXXXX.COM wrote on 09.08.2006 09:23:23: