How users connections are established on RAC ENV

Jhil

Dear RAC Experts,

>> On Node1

Public   : 192.168.212.40

Private  : 10.0.0.1

Virtual  : 192.168.212.70

>> On Node2

Public   : 192.168.212.41

Private  : 10.0.0.2

Virtual  : 192.168.212.71

Cluster may Active-Active or Active Passive !

>> Is this exactly correct ?

User are initially connected to Virtual IP (which is running on NODE1),   then user's  connections are routed to Public IP of the NODE1.

$ lsnrctl status

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 16-JAN-2018 02:05:44

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER)))

STATUS of the LISTENER

------------------------

Alias                     LISTENER

Version                   TNSLSNR for Linux: Version 11.2.0.1.0 - Production

Start Date                16-JAN-2018 02:04:46

Uptime                    0 days 0 hr. 0 min. 59 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /u01/product/11.2.0/grid_home/network/admin/listener.ora

Listener Log File         /u01/app/grid/diag/tnslsnr/RAC1/listener/alert/log.xml

Listening Endpoints Summary...

  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=LISTENER)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.212.40)(PORT=1521)))

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.212.70)(PORT=1521)))

Services Summary...

Service "+ASM" has 1 instance(s).

  Instance "+ASM1", status READY, has 1 handler(s) for this service...

Service "crms" has 1 instance(s).

  Instance "crms1", status READY, has 1 handler(s) for this service...

Service "crmsXDB" has 1 instance(s).

  Instance "crms1", status READY, has 1 handler(s) for this service...

Service "tesco" has 1 instance(s).

  Instance "tesco", status READY, has 1 handler(s) for this service...

Service "tescoXDB" has 1 instance(s).

  Instance "tesco", status READY, has 1 handler(s) for this service...

The command completed successfully

Thanks in advance

SUPRIYO DEY

You will be having another IP called SCAN IP. That routes you to corresponding node listener and load balancing algorithm  decides which node to connect.

Please check local_listener parameter in every node and REMOTE_LISTENER in every node.

local_listener parameter is set to nodes VIP and REMOTE_LISTENER set to SCAN:Port

here is a good doc

https://docs.oracle.com/database/121/JJDBC/scan.htm#JJDBC29161

Omohei

Hi Surriyad ,

where is the SCAN listener . as i noticed you are running 11.2 release . The scan listener is mandatory since this release

Jhil

Hi

Thanks. I will read it ..

Please say clearly  ..

User are initially connected to Virtual IP (which is running on NODE1),   then user's  connections are routed to Public IP of the NODE1

Is that incorrect  ?

SUPRIYO DEY

NO listener runs on VIP not on public IP.

Jhil

Hi,

$ lsnrctl status

LSNRCTL for Linux: Version 11.2.0.1.0 - Production on 16-JAN-2018 17:53:24

Copyright (c) 1991, 2009, Oracle.  All rights reserved.

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=LISTENER)))

STATUS of the LISTENER

------------------------

Alias                     LISTENER

Version                   TNSLSNR for Linux: Version 11.2.0.1.0 - Production

Start Date                16-JAN-2018 17:52:32

Uptime                    0 days 0 hr. 0 min. 52 sec

Trace Level               off

Security                  ON: Local OS Authentication

SNMP                      OFF

Listener Parameter File   /u01/product/11.2.0/grid_home/network/admin/listener.ora

Listener Log File         /u01/app/grid/diag/tnslsnr/RAC1/listener/alert/log.xml

Listening Endpoints Summary...

  (DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=LISTENER)))

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.212.40)(PORT=1521)))

  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.212.70)(PORT=1521)))

Services Summary...

Service "+ASM" has 1 instance(s).

  Instance "+ASM1", status READY, has 1 handler(s) for this service...

Service "crms" has 1 instance(s).

  Instance "crms1", status READY, has 1 handler(s) for this service...

Service "tesco" has 1 instance(s).

  Instance "tesco", status READY, has 1 handler(s) for this service...

Service "tescoXDB" has 1 instance(s).

  Instance "tesco", status READY, has 1 handler(s) for this service...

The command completed successfully

1)  why listener is showing public and VIP ?

2)   SQL> show parameter listener;

NAME                                 TYPE        VALUE

------------------------------------ ----------- ------------------------------

listener_networks                    string

local_listener                       string      (DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=rac1-vip)(PORT=1521))))

remote_listener                      string      rac-scan:1521

$ srvctl status scan_listener

SCAN Listener LISTENER_SCAN1 is enabled

SCAN listener LISTENER_SCAN1 is running on node rac1

SUPRIYO DEY

This is for fail over. Two ip is used .

Jhil

Hi,

I am NOT understanding ..

I am NOT talking about FAIL-OVER.

>> Is this correct exactly ?  - How  normally connection is established on RAC env

1) Users requests are initially handled by SCAN_LISTENER ...

2) SCAN_LISTENER knows which is least loaded node.

3) SCAN_LISTENER should handover  the connection to the listener on the VIP (least loaded node).

4) VIP is routed the the incoming connections to the Public IP.

5) Finally applications and  users are can access RAC Database.

Edited.

Thanks

SUPRIYO DEY

if node public ip is down then?