Re: v$instance -- meaning of INSTANCE_ROLE ?
Date: Wed, 16 Mar 2016 14:57:01 +0000
Message-ID: <1608600295.1117155.1458140221136.JavaMail.yahoo_at_mail.yahoo.com>
> under what circumstances the INSTANCE_ROLE column in
> gv$instance would have a value of 'SECONDARY_INSTANCE'?
Hi Brad,
Before Oracle 11g, if you set active_instance_count=1 on a 2-node RAC, the instance you started later is the secondary instance and will not accept connections unless the instance started first fails. See
ORA-12520 when Connecting to the Second Instance (Doc ID 731241.1)
I don't have 10g RAC I can test on. On 11g, the parameter is deprecated. Although you can still set it (see Doc IC 1480157.1) and v$parameter still shows the value you set, it has no effect, and v$instance.instance_role is always PRIMARY_INSTANCE. The active/secondary instance functionality is done through preferred/standby service. Moving this from instance to listener service is good because the client may be notified earlier about which instance to connect.
Yong Huang
-- http://www.freelists.org/webpage/oracle-lReceived on Wed Mar 16 2016 - 15:57:01 CET