You can run commands on all the compute nodes or cell nodes from a single server on Exadata. We can use the dcli utility for this operation.
Commands can be executed in parallel on desired servers with dcli utility. You can use it as follows.
dcli [options] [commands]
You must configure Secure Shell (SSH) access without password between the server on which you are running dcli and the target servers.(SSH Connectivity)
Use the -g parameter to specify the file that has the names of the destination servers are located. Also, with the-L parameter, we specify the user information to run the command on the target servers. If you do not specify a user with the -l parameter, the command will be executed with the user “celladmin” by default.
First, create the file “dbs_group” which contains the host names of all db nodes and the file “cell_group” which contains the host names of all cell nodes.
Running the hostname command on all db nodes and cell nodes:
[root@dbadm01 ~]# dcli -g dbs_group -l root 'hostname'
[root@dbadm01 ~]# dcli -g cell_group -l root 'hostname'
Querying cell status on cell nodes:
[root@dbadm01 ~]# dcli -g cell_group -l root 'cellcli -e list cell'
celadm01: celadm01 online
celadm02: celadm02 online
celadm03: celadm03 online
As you can see, you can run a command on all servers from a single server and see the result. With this tool, it is possible to perform operations on Exadata very easily on a single server. dcli is an indispensable tool for Exadata.