The cluster name is case-insensitive, must be unique across your enterprise, must be at least one character long and no more than 15 characters in length, must be alphanumeric, cannot begin with a numeral, and may contain hyphens (-). Underscore characters (_) are not allowed.
For 12c, the SCAN is the name of the cluster , If you configure a Standard cluster, and choose a Typical install.
In an Advanced installation, The SCAN and cluster name are entered in separate fields during installation. So you can choose and give cluster name only in “Advanced installation”.
Select cluster name carefully. After installation, you can only change the cluster name by reinstalling Oracle Grid Infrastructure.
Here are a couple of ways to find Oracle Clusterware cluster name:
a) Run “cemutlo” command under GI_HOME/bin.
$cd /u01/app/12.1.0.2/grid/bin
$./cemutlo -n
RACTEST-CLUSTER
b) It is under from $GI_HOME/cdata.
$ cd /u01/app/12.1.0.2/grid/cdata
$ls -l
total 1280
drwxrwxr-x 2 grid oinstall 4096 Sep 19 08:23 RACTEST-CLUSTER
drwxr-xr-x 2 grid oinstall 4096 Sep 18 12:36 racnode1
-rw------- 1 root oinstall 503484416 Sep 19 08:28 racnode1.olr
drwxr-xr-x 2 grid oinstall 4096 Sep 18 12:24 localhost
c) From crsconfig_params or cluster.ini file.
$cd /u01/app/12.1.0.2/grid/crs/install/ $ grep -i cluster_name crsconfig_params CLUSTER_NAME=RACTEST-CLUSTER $cd /u01/app/12.1.0.2/grid/install $cat cluster.ini [cluster_info] cluster_name=RACTEST-CLUSTER
d) From OEM:
e) Run “olsnodes” command under GI_HOME/bin.
$cd /u01/app/12.2.0.1/grid/bin
$./olsnodes -c
RACTEST-CLUSTER
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