OTN APAC Tour, Bangkok, Thailand, 17th Nov, 2014

1. 1
GE Title or job number
12/14/2015
How Oracle 12c Flexes Its Muscles
Against Oracle 11gR2
Ajith Narayanan
Oracle ACE Associate
17th Nov-2014, Bangkok, Thailand.

2. 2
GE Title or job number
12/14/2015
The views/contents in this slides are those of the
author and do not necessarily reflect that of General
Electric Company or Oracle Corporation and/or their
respective affiliates/subsidiaries.
The material in this document is for informational
purposes only, and is provided on an AS-IS basis.
Disclaimer

3. 3
GE Title or job number
12/14/2015
Ajith Narayanan
 10+ years of Oracle [APPS] DBA/Technical Architect experience.
 Oracle ACE Associate
 Blogger :- http://oracledbascriptsfromajith.blogspot.com
 Member:-OAUG, AIOUG
 Website Chair (2011-2013) – Oracle RACSIG
http://www.oracleracsig.org
 AIOUG Real Application Clusters SIG Leader
Who Am I?

4. 4
GE Title or job number
12/14/2015
Take away :
End of the session, we should be able to clearly understand
the high availability features provided by Oracle 12C version.
Agenda
 Introduction
 Oracle RAC – Over the years
 Oracle 11g R2 – Standard Cluster
 Oracle 12c Flex Cluster
 Oracle 12C – Flex ASM
 Conclusion
 Q & A

5. 5
GE Title or job number
12/14/2015
Introduction

6. 6
GE Title or job number
12/14/2015
 Oracle 12C, “C” stands for cloud, this database version
is specially designed for the cloud.
 Heard about CDB, PDB, SEED etc.
 This session is all about, the introduction of high
availability features like Flex Cluster & Flex ASM.
Introduction

7. 7
GE Title or job number
12/14/2015
Oracle RAC – Over the years

8.  Oracle 9i
Database files, OCR & Voting disk on raw devices
 Oracle 10g
ASM for datafiles comes into picture
 Oracle 11g
OCR & Voting disk can be created in ASM too
 Oracle 11g R2
CRS home, ASM Home Consolidated,
Called “Grid infrastructure”
 Oracle 12C
Flex ASM, Flex Cluster
Oracle RAC – Over the years
GI GI GI GI
App1
App2
App3
App4
+ASM
1
+ASM
2
+ASM
3
+ASM
4
• Raw Devices
• Voting Disk
• OCR (9i Days)
+DATA
+FRA
Datafiles

9. 9
GE Title or job number
12/14/2015
Oracle 11g R2 – Standard Cluster

10. • A number of nodes/servers forming a cluster with a shared
storage
• Being a member of the cluster all the nodes typically has the
below running.
 Grid Infrastructure
 ASM
 Listener(s)
 Database Instance(s)
Oracle 11g R2 – Standard Cluster

11. 11
GE Title or job number
12/14/2015
Oracle 12c Flex Cluster

12. • All nodes in an Oracle Flex Cluster belong to a single Oracle Grid
Infrastructure cluster.
• Concept of Hub & Leaf nodes introduced
• Provide high availability , scalability and flexibility
 Hub
Hub Nodes are similar to Oracle Grid Infrastructure nodes in an Oracle
Clusterware standard Cluster configuration.
 Leaf
Leaf Nodes are different from standard Oracle Grid Infrastructure nodes,
in that they do not require direct access to shared storage, but instead
request data through Hub Nodes.
Oracle 12c Flex Cluster

13.  If a Leaf-node has access to shared storage, it can
perform a role change to a HUB-node.
 A Standard Cluster can be converted to a Flex Cluster
at any time after the installation.
 Once a cluster is configured as a Flex Cluster this
configuration is irreversible.
Oracle 12C – Flex Cluster
GI GI GI GI
App1
App2
App3
App4
+ASM
1
+ASM
2
+ASM
3
+ASM
4
+DATA
+FRA
Datafiles
App2
App2
App1
App1
App3
App3
App4
App4
Leaf
Nodes
Leaf
Nodes
Leaf
Nodes
Leaf
Nodes
Hub
Nodes

14. Oracle 12C – Flex Cluster
Flex Cluster can be configured during GI installation

15. Oracle 12C – Flex Cluster
Flex Cluster can be configured using crsctl, later, But remember GNS setup should be done
#cluvfy stage –pre crsinst –n nodelist
#srvctl add gns --domain domain_name --vip vip_name
#srvctl start gns
#cluvfy comp gns --precrsinst --domain domain --vip gns_vip
#srvctl modify network --nettype MIXED
#srvctl update scan_listener
#srvctl update listener
#srvctl update database --db db_unique_name
SQL> alter database set remote_listener=["scan_name:scan_port"];
#cluvfy stage --post crsinst --n all
#srvctl modify network --nettype DHCP
#srvctl update database --db db_unique_name
#srvctl update scan_listener
#srvctl update listener
#srvctl modify scan --scanname scan_name
[root@ajithEBS1~]#crsctl set cluster mode flex
Cluster is configured for ”flex" mode
[root@ajithEBS1~]#crsctl stop crs
[root@ajithEBS1~]#crsctl start crs --wait
[root@ajithEBS1~]#crsctl set cluster mode flex
Cluster is already configured in "flex" mode

16. Oracle 12C – Flex Cluster
Node Roles
 Once the node is converted to a leaf node, check
“crs_stat –t –v” it will have a local listener.
 # of ASM Instances also reduces
 VIP Fails over to available node
[root@ajithEBS1~]#./crsctl get node role config
Node 'ajithEBS1' configured role is 'hub’
[root@ajithEBS1~]#./crsctl set node role leaf
CRS--4408: Node 'ajithEBS1' configured role successfully changed;restart Oracle
High Availability Services for new role to take effect.
[root@ajithEBS1~]#./crsctl stop crs
[root@ajithEBS1~]#./crsctl start crs

17. Oracle 12C – Flex Cluster
 ASM Network
• By default, it will share the interconnect NIC
• Can be changed during install, or later
 Grid Naming Services (GNS), Was optional during 11g days, and /etc/hosts were
a workaround, But in 12C, it is mandatory to have the Grid Naming Service setup
• You can install GI in Standard Mode and reconfigure it with GNS prior to
conversion to Flex Mode.

18. Oracle 12C – Flex ASM

19. Oracle 12C – Flex ASM
 The Next generation Automatic Storage Management (ASM) has a new name
“Flex ASM”.
 Gone are the days, like, One ASM instance per node in a cluster.
 Your ASM configured to run on
fewer nodes in a cluster
 Allows for seamless client
connection failover

20. Oracle 12C – Flex ASM
 Network
 Public Network
 Private Network
 Storage FC/ISCI
 ASM Network
With Oracle Flex ASM you can
– Consolidate all the storage requirements into a
single set of disk groups.
– Small set of Oracle ASM instances running in a single cluster manages all the diskgroups.
– Number of Oracle ASM instances can be set with cardinality setting. The default is three
instances.
[oracle@ajithEBS2~]$srvctl modify asm --count 4
[oracle@ajithEBS2~]$srvctl modify asm --count ALL

21. Oracle 12C – Flex ASM
If installing an Oracle Flex Cluster, Oracle Flex ASM is enabled by default because an Oracle
Flex Cluster requires Oracle Flex ASM.
[oracle@ajithEBS2~]$ asmcmd Showclustermode
ASM cluster : Flex mode enabled

22. Oracle 12C – Flex ASM
Connectivity
 Connections from a database instance to an ASM instance are based on SQLnet
using listeners.
 The listener directs the connection to the least loaded ASM instance based on
the load metric it maintains.
 The ASM instance to which the database instance connects to is listed in the
database alert log
 ASM instance die, it will be restarted automatically
– If an ASM instance crashes, it will be automatically restarted if ASM COUNT is set to ALL
– If an ASM instance crashes, and ASM COUNT is not set to ALL, it will be restarted on the first
available hub node
 41

23. Oracle 12C – Flex ASM
Connectivity
 Connections from a database instance to an ASM instance are based on SQLnet
using listeners.
 The listener directs the connection to the least loaded ASM instance based on
the load metric it maintains.
 The ASM instance to which the database instance connects to is listed in the
database alert log
 ASM instance die, it will be restarted automatically
– If an ASM instance crashes, it will be automatically restarted if ASM COUNT is set to ALL
– If an ASM instance crashes, and ASM COUNT is not set to ALL, it will be restarted on the first
available hub node
 41

24. Oracle 12C – Flex ASM
Why use Oracle Flex ASM
 Oracle Flex ASM supports larger LUN sizes for Oracle Database 12c clients.
 Maximum number of Disk Groups supported is 511.
 Flexibility to rename an ASM Disk in a Disk Group.
Network enhancement in Oracle Flex ASM
 In previous versions the cluster requires:
- A public network for client application access
- One or more private networks for inter-node communication within the
cluster including ASM traffic.
 Flex ASM adds the ASM network, which can be used for communication between
ASM and its clients to isolate and offload ASM traffic Physical Metadata

25. Conclusion

26. – Clients are automatically relocated if an ASM Instance goes down
– Adding a new node to a cluster (which currently exists as a standalone) and
migration to ASM is easier
– Even though with previous releases, there is very little over-head of ASM
• Fewer resources on a Hub nodes without ASM to manage
– The database is not the super-star in the cluster!
Conclusion

27. Q & A

28. Thank You
Please contact me
@ ajithpathyil@gmail.com or
http://oracledbascriptsfromajith.blogspot.com