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warm standby synch up

i have a question regarding sybase replication warm standby sync up and appreciate the clarification.

let us suppose in a warm standby setup, the standby data has gone out of sync with the primary database.

the log contains committed as well as uncommitted data.

but even uncommitted data is sent to rep server.

so in a tran log let us suppose there are 12 transactions. till transaction 7, it has been committed on the primary database (that i think is the primary truncation point).

and let us suppose that the secondary truncation point is at the 9th transaction - till which data has been sent to the rep server.

but we do the dump database at the 12th transaction, where the dump marker is inserted.

so when we load the database dump into the primary, it will start accepting replicated transactions from the 12th transaction - from where the dump marker starts.

so in this case won't the transactions from 7 to 12 be missed?

the above case assumes a scenario where the sync up can be done without doing a dump tran of the primary database. or does a warm standby sync up always require a dump tran with truncateonly/nolog, of the primary database (and also the related rs_zeroltm etc)?

I think with 15.6 there is a new way to do the sync up. but here I am referring to the pre-15 versions.

appreciate the clarification.

thanks,

nanda chandran

Former Member
replied

Think of the entries in the transaction log as being in single file, eg, 1,2,3,4,5 ...

The dump marker (DM) is placed into the transaction log along with the transactions, eg:

1,2,3,4,5,6,7,8,9,10,11,12,DM,13,14,15,...

The database dump will contain all transactions up to #12.

The repserver will apply transactions 1-12 as normal to the standby database.  When the DM is processed the DSI (for the standby database) will shutdown.  All transactions coming after the DM (eg, 13,14,15,...) will queue up waiting for the DSI to be resumed.

When the dump file is loaded all transactions up to #12 will also be loaded/applied in the standby database.

When the DSI is resumed the queued transactions (13,14,15,...) will be applied to the standby database,

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