Wednesday, July 31, 2013

Implementing Parallel Concurrent Processing (PCP) in Oracle Apps


In oracle apps, by default, concurrent managers are installed on one of the nodes. However, Oracle provides functionality called parallel concurrent processing -PCP where in, we can install concurrent mangers on multiple nodes.  The advantage of PCP is that it provides fail over capability-if one of the nodes having Cm goes down, then CM will run on other nodes. Also, since we can distribute Cm over multiple nodes, so it will take advantage of resources-Ram/CPU of that node and hence processing will be faster.
Steps for Implementing PCP
  • Make sure that the new node is added to the system. We will call the node already having   CM  as primary node and the new node as secondary node.
  • Change the parameter APPLDCP to ON in context file of both nodes. For viewing reports log/output make sure that $APPLSCF should point to same directory on both nodes. We can use NFS for this.
  • ON the secondary node, change the parameter “s_ isConc” to yes and also”s_ isConcDev” to yes
  • Now, shutdown the services and run autoconfig on primary node, then on secondary node and finally on web tier.
  • Ensure that tnsnames.ora on both CM nodes have correct entries.
  • Now define primary and secondary node for ICM. Goto Concurrent >Manager>Define >Internal manager. There should be 2 ICM-one  for each node(say node A and  node B). For ICM for node A-define A as primary node and B as secondary node. For ICM for Node B-define B as primary node and A as secondary node.
  • Similarly for Internal Monitor process define primary and secondary nodes. Goto  Concurrent > Manager > Define. Search “Internal Monitor%”.  There should be 2 Internal Monitor -one for each node(say A and B). For Internal Monitor for node A-define A as primary node and B as secondary node. For Internal Monitor for Node B-define B as primary node and A as secondary node. Also define standard workshift for both Internal Monitors. Activate them.
  • Now define primary and secondary for other concurrent managers the way you want to distribute them.
  • Start the services on all nodes. The cm has to be started on primary node only and not on secondary node.

References-Please refer to the following oracle metalink notes for further details-
Note: 388495.1 - How to Set Up Parallel Concurrent Processing (PCP) in Apps 11i
Note: 602899.1 - Some More Facts On How to Activate Parallel Concurrent Processing
Note: 271090.1 - Parallel Concurrent Processing Failover/Failback Expectations

Wednesday, July 24, 2013

Shared Appl_Top and Shared Application Tier file System



In a traditional oracle apps file system, each node had separate APPL_TOP,COMMON_TOP,apps stack components. With this configuration, if an oracle app patch had to be applied, it need to applied on each node.

In a shared APPL_TOP- APPL_TOP and COMMON_TOP are shared among multiple nodes. Basically, the APPL_TOP and the COMMON_TOP file systems are installed on a shared disk resource which is mounted to each node. However, each node will have separated apps stack component s(IAS_ORACLE_HOME and 8.0.6 ORACLE_HOME)

In a shared Application tier file system-APPL_TOP,COMMON_TOP and Apps tech stack(IAS_ORACLE_HOME  and 8.0.6 ORACLE_HOME) are shared among multiple nodes. So basically,  APPL_TOP,  COMMON_TOP, and the Applications technology stack (ORACLE_HOMEs) are installed on a shared disk resource which is mounted to each node.

Earlier it was shared APPL_TOP and then oracle came out with shared application tier .

All the machines sharing the file system must be configured to run the same Operating System with the same OS patch level. With shared APPL_TOP  and shared application tier file system, oracle apps patch had just to be applied once. However if the patch runs autoconfig (AD patch) then we need to run autoconfig on all the nodes.

Also, on a shared APPL_TOP, if we are applying any patch on 8.0.6 ORACLE_HOME or iAS ORACLE_HOME, then we need to apply it on each application node since the techstack is not shared.

There is a restriction that if you are on Windows, then you CANNOT use shared appl_top/shared application tier.