SSL certificates and some other parameters are missing from the configuration of NetScaler VPX after a reboot. 

Note: The expiration of licenses typically only happens with partner, demo, internal only, express and developer edition licenses. Regular retail licenses are usually issued without an end date, so verify if this really is a licensing issue before proceeding.

To resolve this issue restore the NetScaler configuration from an old saved configuration. If you have a backup, you can use this, otherwise you can use the automatically saved configuration on the NetScaler.

1. Install a new license, see https://docs.citrix.com/en-us/netscaler-gateway/12/licensing/ng-license-install-tsk.html for more information.
   Note: If you want to revert back to the same configuration, then ensure that you have a license which supports the same features that you had before, or be certain that you do not require the missing features. Refer to NetScaler Datasheet for the list of all features and license types.

2. Ensure that you see all the features that you need as enabled through the GUI or CLI:

   

3. Log on to the NetScaler CLI with SSH using ssh nsroot@<ip-address> and change to the Shell by typing shell.

4. Change the directory to /nsconfig to view all configuration objects of the NetScaler.
   If you have saved multiple times before then you will find multiple versions of the NetScaler configuration as shown in the following example:

   1 -rw-r--r--   1 root  wheel  34425 Dec  5 21:24 ns.conf
   2 -rw-------   1 root  wheel  39247 Dec  5 21:24 ns.conf.0
   3 -rw-------   1 root  wheel  39316 Dec  5 21:24 ns.conf.1
   4 -rw-------   1 root  wheel  39316 Dec  5 16:10 ns.conf.2
   5 -rw-------   1 root  wheel  39255 Dec  5 14:54 ns.conf.3
   6 -rw-------   1 root  wheel  39321 Nov 28 23:10 ns.conf.4

5. Notice that the file after the license expiration is smaller than the files from before. The save file ns.conf is smaller in size when compared to the earlier created ns.conf.0 file.

   Warning! All changes made after the date of the file that you are restoring will be lost however the changes are still maintained in the configuration that you back up. Do not save any configurations or make any other changes.

   Move the ns.conf file to a backup folder, copy the ns.conf.0 file (or any recent version that you would like to restore) to ns.conf folder and reboot. From CLI type:
   Shell
   mv ns.conf ns.conf.licbck
   cp ns.conf.0 ns.conf
   reboot

6. If all the preceding steps are completed successfully then NetScaler will return to normal working condition.

Problem Cause

When a license on a NetScaler expires the non-licensed features and certificates greater than 512 bits are removed from the configuration which is by design.

Always ensure to take a back up of the NetScaler, so you can revert to the previous configuration when needed. Refer to Citrix eDocs - Backing up a NetScaler Appliance for more information on this procedure.

When the license on a NetScaler expires the configuration is altered. Non-licensed features are disabled and certificates greater than 512 bits are removed from the configuration. Also the throughput of the NetScaler will fallback to 1 Mbps. The easiest way to determine this is to look at the top-left of the NetScaler which will display NetScaler VPX 1. VPX 1 is typically unlicensed or a developer license (that you can recognize by having all the features available).