Reverting to a previous level of GPFS when you have not issued mmchconfig release=LATEST

If you have not issued the mmchconfig release=LATEST command, perform these steps.

Stop all user activity in the file systems.
Cleanly unmount all mounted GPFS™ file systems. Do not use force unmount.
Stop GPFS on all nodes in the cluster:
```
mmshutdown -a
```
Run the appropriate uninstallation program to remove GPFS from each node in the cluster. For example:
- For Linux nodes (this example is only applicable on the IBM Spectrum Scale™ Express Edition):
```
rpm -e gpfs.gpl gpfs.base gpfs.docs gpfs.gskit gpfs.msg.en_US
```
- For AIX® nodes:
```
installp -u gpfs
```
- For Windows nodes, open the Programs and Features control panel and remove IBM General Parallel File System.
For the remaining steps, see IBM Spectrum Scale in IBM® Knowledge Center, and search for the appropriate IBM Spectrum Scale: Concepts, Planning, and Installation Guide for your release.
Copy the installation images of the previous GPFS licensed program on all affected nodes.
Install the original install images and all required PTFs.
For Linux nodes running GPFS, you must rebuild the GPFS portability layer.
Reboot all nodes.