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 Differences between DMSETPOS and DMMRKPOS

Alfredo Rendon's profile image
PARTNER Alfredo Rendon posted 08-16-2021 15:34
Hi Rocket Forum,

Sometimes, when it’s time to start a replication group we can use “dmsetpos” to set the sequence of each journal, but we have also “DMMRKPOS”. So the main question it’s;

what are the differences between both?
when it’s about get a group back up which it’s the better command to use ?
don broadbridge's profile image
ROCKETEER don broadbridge posted 08-17-2021 03:25
Hi Alfredo,

The DMMRKPOS command is used to establish the starting journal positions for mirroring on a replication group. 
The journal positions are recorded in the iCluster metadata on the primary node that is associated with the group. Marking a journal position takes a "snapshot" of the state of the primary node and the objects that match the object specifiers at the time the command is issued.  The marked positions are used in the DMSTRGRP command.

The DMSETPOS command is used to position iCluster to start replication at a specific entry in a database journal, system audit journal, or all journals scraped by a group. The specific journal entry can be entered directly or determined by the command if a date and time is entered.

The 2 keywords are underlined above, with the mark You are establishing where to start a groups journal positions, with the set You are saying where you want to the journal starting position should start from, e.g. date/time, *LASTAPY, *CURCHAIN

Thanks