Enabling or disabling sudo

Enabling sudo requires a sudo-capable user (gpfsadmin) to be added to all nodes which are a part of or which are going to be a part of an IBM Storage Scale System cluster. Sudo must be enabled for management server and I/O server nodes by using the sudo sub-command of the essrun command.

Note: Sudo user across all GPFS nodes must have the same Linux® group ID and user ID.

Enabling sudo on IBM Storage Scale System

You can enable sudo configuration on a Linux node by using the enable option of the sudo sub-command.

# essrun -N nodeList sudo enable

Note: To configure a sudo user, see the essrun sudo command in the IBM Storage Scale System: Command Reference.

This command creates the gpfsadmin Linux user and gpfs Linux group on the node and performs all necessary sudoers set up. For detailed information, see the /etc/sudoers.d/ess_sudoers file.

User can now log in to the node server using the gpfsadmin user and they can perform GPFS administration tasks.

Make sure that the sudo sub-command is run on all GPFS nodes (management server node, I/O server nodes, and any client nodes) as part of the cluster to be completely compliant with the sudo requirement. Change the node name in the sudo sub-command accordingly. Enabling sudo also allows the gpfsadmin user to administer xCAT and the GPFS GUI on the management server node.

Disabling sudo on IBM Storage Scale System

You can disable sudo configuration on a Linux node by using enable option of the sudo sub-command.

# essrun -N nodeList sudo disable

Disabling sudo reverts the xCAT policy table to its previous state, deletes /etc/sudoers.d/ess_sudoers file, and deletes the gpfsadmin user from the Linux node. Make sure that you have disabled sudo user configuration on all GPFS nodes (management server node, I/O server nodes, and any client nodes) as part of the cluster to be completely compliant with the sudo requirement. Change the node name in the sudo sub-command accordingly.

Important: You must not disable sudo user until the GPFS cluster is set to configure not to use sudo wrapper and sudo user. Failing to do so might result in cluster corruption.

Enabling root access on IBM Storage Scale System

To enable root access, issue the following command:

# essrun -N nodeList sudo enable_root --sudo-password YourSudoPassword

Disabling root access on IBM Storage Scale System

To disable root access, issue the following command:

# essrun -N nodeList sudo disable

Note: You can disable root in all IBM Storage Scale System nodes except IBM Storage Scale System 3000.