Managing software on diskless and dataless clients
The /usr and root file systems of diskless and dataless clients are resources that have been mounted from a server. Therefore, in order to install or uninstall software on a diskless or dataless client, the processing must actually occur on the resources that the clients use.
The SPOT contains the directory structure for an installed /usr file system. It also contains subdirectories for the "root" parts of installed filesets. Because the SPOT contains both usr and root files, software maintenance must be performed on the SPOT in order to update the software that is running on the clients. Such actions must be performed using the NIM cust and maint operations. For more information about the cust and maint operations, see Using NIM operations.
If the SPOT is currently allocated for client use, NIM will prevent software customization operations from being performed on it. This is to safeguard the SPOT from changes that may adversely affect running client machines. However, this restriction can be overridden by specifying the force option when performing the operation unless there are shared_root objects that were defined from the SPOT and are allocated for client use.
When NIM is used to install software in a SPOT, the following operations are performed to manage the software for diskless and dataless clients:
- The /usr files are installed in the SPOT. These files are automatically seen by all the clients that mount the SPOT as their /usr file systems.
- The root files are installed in special subdirectories in the SPOT.
- After all the filesets have been installed in the SPOT, the root files are copied to the root directories of any diskless or dataless clients that have been initialized with the SPOT and to any shared_root directory that has been defined from the SPOT.
When NIM is used to uninstall software in a SPOT, the following operations are performed to manage the software for diskless and dataless clients:
- The /usr files are removed from the SPOT. This also automatically "removes" the files from the client systems.
- The root files of the software are removed from the client root directories and from any shared_root directory that has been defined from the SPOT.
NIM also provides a sync_roots operation to perform consistency verification and correction to ensure that the client root directories, and the shared_root directories defined from the SPOT, match the root parts stored in the SPOT.