Creating services with srvctl

In a RAC environment we can create services and run these services on a specific RAC instance/node (or a set of instances/nodes). This makes it possible for the applications to connect to specific instances. In this article I would explain how we create a service and make it run on the instance(s) of our choice, and make it automatically failover to another instance/node if current instance node goes down.

Following set of commands/outpts shows how we create a new service for my database that will run on instance1/node1 (as specified in “-preferred” argument, and failover automatically to instance2/node2 (as specified in argument “-avialable” ), in case instance1/node1 goes down.

-- Create a service. For Oracle versions lower than 12c, use –d, -s, -r, and -a arguments respectively.

[oracle@salman11 ~]$ srvctl add service -db salman12 -service salman12_service -preferred salman121 -available salman122

-- Start the service. For Oracle verions lower than 12c, use –d, and –s arguments respectively.

[oracle@salman11 ~]$ srvctl start service -db salman12 -service salman12_service

-- Check status of service. For Oracle verions lower than 12c, use –d, and –s arguments respectively

[oracle@salman11 ~]$ srvctl status service -db salman12 -service salman12_service

Service salman12_service is running on instance(s) salman121

-- Check configuration of service. For Oracle verions lower than 12c, use –d, and –s arguments respectively.

[oracle@salman11 ~]$ srvctl config service -db salman12 -service salman12_service

Service name: salman12_service

Server pool:

Cardinality: 1

Service role: PRIMARY

Management policy: AUTOMATIC

DTP transaction: false

AQ HA notifications: false

Global: false

Commit Outcome: false

Failover type:

Failover method:

TAF failover retries:

TAF failover delay:

Failover restore: NONE

Connection Load Balancing Goal: LONG

Runtime Load Balancing Goal: NONE

TAF policy specification: NONE

Edition:

Pluggable database name:

Maximum lag time: ANY

SQL Translation Profile:

Retention: 86400 seconds

Replay Initiation Time: 300 seconds

Drain timeout:

Stop option:

Session State Consistency: DYNAMIC

GSM Flags: 0

Service is enabled

Preferred instances: salman121

Available instances: salman122

CSS critical: no

You can also check she status of service using crsctl command.

[grid@salman11 ~]$ crsctl stat res -t

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

Name Target State Server State details

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

…

ora.salman12.db

1 ONLINE ONLINE salman11 Open,HOME=/u01/app/o

racle/product/12.2.0

/dbhome_1,STABLE

2 ONLINE ONLINE salman12 Open,HOME=/u01/app/o

racle/product/12.2.0

/dbhome_1,STABLE

ora.salman12.salman12_service.svc

1 ONLINE ONLINE salman11 STABLE

…

If you check status of the listener, you will see this service registered with the listener on node1 (where instance salman121 is running)

[grid@salman11 ~]$ lsnrctl status

LSNRCTL for Linux: Version 12.2.0.1.0 - Production on 27-APR-2017 15:16:53

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

STATUS of the LISTENER

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

Alias LISTENER

Version TNSLSNR for Linux: Version 12.2.0.1.0 - Production

Start Date 27-APR-2017 13:39:47

Uptime 0 days 1 hr. 37 min. 5 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Parameter File /u01/app/12.2.0/grid/network/admin/listener.ora

Listener Log File /u01/app/grid/diag/tnslsnr/salman11/listener/alert/log.xml

Listening Endpoints Summary...

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

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.231.231.50)(PORT=1521)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.231.231.60)(PORT=1521)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=salman11.salman.com)(PORT=5500))(Security=(my_wallet_directory=/u01/app/oracle/product/12.2.0/dbhome_1/admin/salman12/xdb_wallet))(Presentation=HTTP)(Session=RAW))

Services Summary...

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

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

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

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

Service "4e202176e59f367be05332e7e7c0461b.salman.com" has 1 instance(s).