Unable to see all the virtual servers that are present on an instance using NetScaler MAS.
Complete the following steps to resolve this issue:
Note: By default NMAS will monitor 30 Virtual server. However you have an option on NMAS to see specific vserver data.
Verify the licenses allocated for NetScaler MAS and the virtual servers it supports. You can see this information under Infrastructure > Licenses > System Licenses.
Remember the license limit that you see in the above snapshot comprises of all the Virtual Server on the instances including Gateway VIP and GSLB VIP.
When you locate the virtual server, navigate to Choose Virtual Servers Page again and select the virtual servers you do not need. Then click Mark Unlicensed. You can then replace it with the virtual server that you need.
Alternately, you can go to /var/log/ns.log and try to search for these errors which confirms that the NetScaler MAS has more virtual servers than license limit allocated:
Mar 21 18:22:34 <local0.err> NetScaler MAS-1 mas_event: 10.107.143.118 03/21/2017:12:52:34 GMT : EVENT VIPLICENSELIMITWARNING : 127.0.0.1:VIPLicenses - System discovered more Virtual Servers than license limit, dropping 1 vipsThe NetScaler MAS has more virtual servers than license limit allocated.
To upgrade the licensing on NetScaler MAS to monitor and manage more virtual servers hosted on the NetScaler appliances refer to Citrix Documentation - Upgrading the Virtual Server Licenses.