Cluster Verification Utility CLUVFY

CLUVFY utility is distributed with Oracle Clusterware. It is used to assist in the installation and configuration of Oracle Clusterware as well as RAC. It helps in verifying whether all the components that are required for successful installation of Clusterware and RAC are installed and configured correctly.


The CLUVFY commands are divided in to two categories,


1. Stage Commands
2. Component Commands


Stage Commands:


There are various phases during clusterware or RAC deployment, for example, hardware and software cofiguration, CRS installation, RAC software installation, Database creation etc...Each of these phases is called a stage. Each stage requires a pre-requisite conditions to be met before entering the stage (pre check) and another set of conditions to be met after the completion of that stage (post check)..


The pre-check verification and post check verification can be done using the CLUVFY commands. The commands used to perform these pre-check and post-check are called stage commands. To identify various stages use the following command,


$ cd ORA_CRS_HOME/bin
$ cluvfy stage -list


post hwos - Post check for hardware and Operating System
Pre cfs - Pre check for CFS (optional)
post cfs - Post check for CFS (optional)
pre crsinst - pre check for clusterware installation
post crsinst - post check for clusterware installation
pre dbinst - pre check for database installation
pre dbcfg - pre check for database configuration



Component Commands:


The commands in this category is used to verify the correctness of an individual cluster components and not associated with any stages. The various cluster components are listed using the following command,


$ cd $ORA_CRS_HOME/bin
$ cluvfy comp -list


nodereach - checks reachability between nodes
nodecon - checks node connectivity
cfs - checks cfs integrity
ssa - checks shared storage accessibility
space - checks space availability
sys - checks minimum system requirements
clu - checks cluster integrity
clumgr - checks cluster manager integrity
ocr - checks ocr integrity
nodeapp - checks existence of node applications
admprv - checks administrative privileges
peer - Compares properties with peers

Thanks

Network Time Protocol (NTP)

Network Time Protocol (NTP) is a protocol for synchronizing the clocks of computers in a network of computers. If you were to set up a RAC environment, one of the requirement is to synchronize the clock time of all your RAC nodes to avoid unnecessary node eviction. Time difference of more than 15 mins among nodes may cause node evictions. Also the trace file analysis and GV$ view analysis may not be accurate if the time is not synchronized among nodes.



Configuring NTP:

NTP configuration has 3 files in the /etc folder

ntp.conf
ntp.drift
ntp.trace


Add the names of the nodes in the ntp.conf file along with the names of drift and trace file as shown in the picture below.



cmsprod1 and cmsprod2 are the node names..



Add this information in all the nodes participating in the cluster.
Leave the drift and trace files as it is..

Thanks.