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On 8 aug, 13:44, keith..._at_comcast.net wrote:
> Got the configuration piece now. thanks
>
> Just to confirm the network behavior (per Brian's earlier post) in a 3
> node RAC. If clients are attaching to the VIP that is listening on
> Node 1 and then Node 1 has a failure. Assuming Node 1's VIP is now
> on Node2, will the clients actually keep their seesions processing to
> the Node 1 VIP or will they now select the next connection name (that
> of Node 2's VIP) stated in the client's conection list?
>
> I'm use to the concept of VIP's in the Cisco world where the VIP
> remains the same IP address regardless of the services it supports
> behind it. Or also with HACMP where a service IP address (VIP)
> remains the same IP address regardless of what server it resides on.
>
> Thanks
> Keith
VIP's are used for connect time failover. If the node fails where your
session is running, OracleNet will reconnect all over again (using the
original connect descriptor). This is all controlled behind the
'scenes' (OracleNet will capture certain ORA failures and reconnect,
without the client knowing). When it tries the failed over VIP it will
receive an oracle error (no listener, if i'm correct) and try to
connect through another VIP.
When reconnected to another instance, it will restart your original
query (depending on your failover options in your connect descriptor).
If you had received 50 of the 100 resulting rows from your original
connection,it will 'filter' the original presented rows from the
output from the failover connect and then output the remaining rows.
So in a way connection failover just automates, reconnect including
any query your were running (its using flashback query, probably). DML
will NOT be restarted!
regards, Tony van Esch Received on Wed Aug 08 2007 - 14:48:57 CDT