You can downgrade to any release on a standalone NetScaler or a high availability pair by using the command line interface.
cp ns.conf.NS<releasenumber> ns.conf
If the configuration file for the build that you are downgrading to exists on the appliance, you are prompted to load that configuration, as shown in the following figure.
If the free space available on the flash drive is insufficient to install the new build, the NetScaler prompts you to initiate a cleanup of the flash drive. For more information, see "Auto Cleanup".
login: nsroot Password: nsroot Last login: Thu Jun 18 02:06:52 2015 from 10.102.29.9 Done > save config > shell root@NSnnn# cp ns.conf.NS10.5 ns.conf root@NSnnn# cd /var/nsinstall root@NSnnn# mkdir 10.5nsinstall root@NSnnn# cd 10.5nsinstall root@NSnnn# mkdir build_57 root@NSnnn# cd build_57 root@NSnnn# ftp 10.102.1.1 ftp> mget build-10.5-57_nc.tgz ftp> bye root@NSnnn# tar -xzvf build-10.1-125_nc.tgz root@NSnnn# ./installns installns version (10.5-57) kernel (ns-10.5-57.gz) ... ... ... Copying ns-10.5-57.gz to /flash/ns-10.5-57_nc.gz ... Changing /flash/boot/loader.conf for ns-10.5-57 ... Installation has completed. Reboot NOW? [Y/N] Y
To downgrade the system software on NetScaler units in a high availability pair, you need to downgrade the software first on the secondary node and then on the primary node. For instructions on downgrading each node separately, see "Downgrading a Standalone NetScaler".