you need to upgrade all the databases to 12cR1?

If you upgrade to ASM 12cR1 and implement Flex ASM, do you need to upgrade all the databases to
12cR1?

A.
Yes. All the databases need to be upgraded to 12cR1.

B.
No. You can run in a mixed 11.2 database instance and a 12cR1 database instance. The 11.2
instance will use the Flex ASM instance of the other server.

C.
No. You can run in a mixed 11.2 database instance and a 12cR1 database instance, but the
11.2 instance will fail if the local Flex ASM instance is moved to another server.

D.
No. You cannot upgrade your database instance to 12cR1.

Show Hint

← Previous question

Next question →

Leave a Reply 3

Prabhat

Click to add to Favorites FAQ: Oracle Flex ASM 12c / 12.1 (Doc ID 1573137.1) To BottomTo Bottom

In this Document
Purpose
Questions and Answers
What is Oracle Flex ASM?
What is Oracle Proxy ASM Instance?
What is the difference between Oracle Flex Cluster vs Oracle Flex ASM?
What is ASM Network and ASM listener?
How to implement Flex ASM feature?
How to check Oracle Flex ASM has setup?
How to change the cardinality of the ASM to be up in the cluster?
How to relocate Database client to different ASM?
How to check ASM instances running nodes?
How to convert Non-Flex ASM to Flex ASM (vice-versa)
References
APPLIES TO:

Oracle Database – Enterprise Edition – Version 12.1.0.1 to 12.1.0.2 [Release 12.1]
Oracle Virtual Compute Appliance X4-2 Hardware – Version All Versions to All Versions [Release All Releases]
Information in this document applies to any platform.
PURPOSE

To provide answers to common questions regarding the 12c New Feature “Oracle Flex ASM”

QUESTIONS AND ANSWERS

What is Oracle Flex ASM?

Oracle Flex ASM is an ASM instance which will be running in the cluster based on cardinality defined.The default cardinality is three,but you can change it using srvctl modify asm command.It means that ASM is not required to run on each node in the cluster.

In previous release,ASM will be running on each node in the cluster and ASM clients (Database,ACFS,ADVM) can only access ASM by using an ASM on the same host.

With Oracle Flex ASM,the clients can connect to remote ASM using network connection (ie ASM network ).If a server running an ASM instance fails, Oracle Clusterware will start a new ASM instance on a different server to maintain the cardinality. If a 12c database instance is using a particular ASM instance, and that instance is lost because of a server crash or ASM instance failure, then the Oracle 12c database instance will reconnect to an existing ASM instance on another node.These features are collectively called Oracle Flex ASM.

What is Oracle Proxy ASM Instance?

Oracle ASM proxy instance will be configured to support the ACFS/ADVM.An oracle ASM proxy instance can run on the same node as ASM instance or on a different node in a flex ASM.

below picture shows ACFS/ADVM on node 2 talks to Oracle ASM proxy on the same node,which connects to Oracle ASM instance on remote node 1.

ASM proxy instance

What is the difference between Oracle Flex Cluster vs Oracle Flex ASM?

Oracle Flex Cluster is a cluster node with Hub and leaf node configuration.only Hub nodes have direct access to OCR and Voting disk.leaf node do not have direct access to shared storage.

Flex Cluster require Flex ASM. Flex ASM does not require a Flex Cluster.
In Flex cluster node,the Flex ASM can run on the Hub nodes servicing clients across the Hub nodes of the Flex cluster.

The default Oracle Flex Cluster is disabled,users explicity enable Flex Cluster functionality.

What is ASM Network and ASM listener?

In previous 12c ,the Oracle clusterware required a public network for client access and a private network for inter-node communication including ASM inter-node communication in the cluster.

In Flex ASM,ASM network provides the capability to isolate ASM’s internal network traffic to its own dedicated private network. The OUI presents the DBA with the choice as to whether a dedicated network is to be used for ASM. The ASM network is the communication path in which all the traffic between database instances and ASM instances commence. This traffic is mostly the metadata such as a particular file’s extent map. If the customer chooses, the ASM private network can be dedicated for ASM traffic or shared with CSS and a dedicated network is not required.

There will be local ASM listener runs on each node where the flex ASM instance is running.ASM clients connect to Flex ASM over the ASM network by using highly available connection endpoints supplied by up to three ASM listeners.Connections are load balanced across the ASM cluster.

How to implement Flex ASM feature?

The flex ASM can be implemented in the below ways

* Pure 12c Flex ASM – In this mode the Grid Infrastructure and Database are both running the 12c version. In this model, the database fully leverages all the new 12c features

* Pre 12c Mixed – This mode the ASM will run on each node with Flex configuration to support pre 12c database .To achive this, set the the ASM cardinality to “all” which insures that there is an ASM instance on every server in a cluster. The advantage of this approach is that if an Oracle 12c database instance loses connectivity with an ASM instance, then the database connection will failover to another ASM instance on a different server.

Reply

Prabhat

B >>>>>

There are two ways to achieve this mixed model of operation –

1. Install cluster in in Standard Mode

2. Install Oracle Flex ASM and set cardinality to “all”  which insures that there is ASM instance on every server in a cluster. Advantage of this is if database instance loose connectivity with asm instance then database connection will failover to another ASM instance on a different server.