BASIC and PRECONNECT failover methods

Version: 10.2.0.4, 11.2

That's what documentation says BASIC and PRECONNECT

http://download.Oracle.com/docs/CD/B28359_01/network.111/b28316/advcfg.htm#i471200
basic: Set to establish connections at failover time. This option requires almost no work on the backup server until failover time.

preconnect: Set to pre-established connections. This provides faster failover but requires that the backup instance be able to support all connections from every supported instance.
So, if I configure PRECONNECT to a customer, then for each session created by this session a backup session is created (Preconnected) to another node. This means that, if the customer creates 100 sessions with the Node1, and then another 100 backup sessions will be connected to Node2 (backup instance). Right?

These pre-processed sessions will appear in v$ session of the Forum of backup? If so, how can I determine if an entry in V$ SESSION is actually a backup session (Preconnected)?

>

So, if I configure PRECONNECT to a customer, then for each session created by this session a backup session is created (Preconnected) to another node. This means that, if the customer creates 100 sessions with the Node1, and then another 100 backup sessions will be connected to Node2 (backup instance). Right?

Yes...

>

These pre-processed sessions will appear in v$ session of the Forum of backup?

Yes...

If so, how can I determine if an entry in V$ SESSION is actually a backup session (Preconnected)?

Check using query below:

Select
user name,
SID,
Serial No.,
failover_type,
failover_method,
failed_over
Of
session v$
where
user name not in ('SYS', 'SYSTEM',
'PERFSTAT')
and
failed_over = 'YES ';

Tags: Database

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