I'm trying to learn my way around Cisco switches by watching an online course  and trying the commands from there on a switch I have access to. One of the first commands I've tried,
show vlan brief, doesn't seem to be supported on the switch I tried it on. Could you help me to figure out why is it so? Do different versions of IOS have different ways of configuring VLANs? Or my switch doesn't have this feature enabled? Or maybe I'm doing something completely silly, and is not in the right mode or something?
Here's output from the console:
RP/0/RP0/CPU0:xy16.nuq09#show license ^ % Invalid input detected at '^' marker. RP/0/RP0/CPU0:xy16.nuq09#show version Fri Aug 28 14:11:27.261 PDT Cisco IOS XR Software, Version 6.5.3 Copyright (c) 2013-2019 by Cisco Systems, Inc. Build Information: Built By : ahoang Built On : Tue Mar 26 06:35:07 PDT 2019 Built Host : iox-ucs-025 Workspace : /auto/srcarchive13/prod/6.5.3/ncs5k/ws Version : 6.5.3 Location : /opt/cisco/XR/packages/ cisco NCS-5001 () processor System uptime is 36 weeks 3 days 3 hours 5 minutes RP/0/RP0/CPU0:xy16.nuq09#show vlan? ^ % Invalid input detected at '^' marker. RP/0/RP0/CPU0:xy16.nuq09#show vlan ^ % Invalid input detected at '^' marker.