This is usually time consuming and there are two way that you can achieve it
1 In an ideal world you would use Tacacs/Radius server and give each user set of commands that they can execute
2 You can use the router to achieve a similar thing as the Radius/Tacacs server using 'username name privilege 5 password password', and attaching set of commands to that level, for example "privilege exec level 5 show ip route" which will allow them to run that command, When someone logs in with that username and password they can only run the commands that are allowed for that level
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Don't be content with being average. Average is as close to the bottom as it is to the top
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