For example, suppose you want to configure the primary DNS server settings on the Palo Alto Networks device using find command keyword with dns as the keyword value, you already know that the command is set deviceconfig system dns-setting, but you’re not exactly sure how to use the command to set the primary DNS server setting. In this case, you would enter as much of the command as you know (or start typing it and press Tab for automatic command completion), and then add a question mark at the end of the line before pressing Enter, like this:

username@hostname# set deviceconfig system dns-setting ? 
> dns-proxy-object Dns proxy object to use for resolving fqdns 
> servers Primary and secondary dns servers 
<Enter> Finish input 

Notice that the question mark doesn’t appear in the command line when you type it, but a list of the available commands appears. You can continue getting syntactical help all through the hierarchy:

username@hostname# set deviceconfig system dns-setting servers ? 
+ primary Primary DNS server IP address 
+ secondary Secondary DNS server IP address 
  <Enter> Finish input 
 
username@hostname# set deviceconfig system dns-setting servers primary ? 
<ip> <ip>