Getting Help About Commands

Information about commands is provided at each level of the CLI command hierarchy. You can type a question mark to get help about commands:

• If you type the question mark at the command-line prompt, the CLI lists the available commands and options. For example, to view a list of top-level operational mode commands, type a question mark (?) at the command-line prompt.
  user@host> ?

  Possible completions:
  clear       Clear information in the system
  configure   Manipulate software configuration information
  file        Perform file operations
  help        Provide help information
  mtrace      Trace mtrace packets from source to receiver.
  monitor     Real-time debugging
  ping        Ping a remote target
  quit        Exit the management session
  request     Make system-level requests
  restart     Restart a software process
  set         Set CLI properties, date, time, craft display text
  show        Show information about the system
  ssh         Open a secure shell to another host
  start       Start a software process
  telnet      Telnet to another host
  test        Diagnostic debugging commands
  traceroute  Trace the route to a remote host

  
  user@host>
• If you type the question mark after entering the complete name of a command or command option, the CLI lists the available commands and options and then redisplays the command names and options that you typed.
  user@host> clear ?

  Possible completions:
  arp 	      Clear address-resolution information
  bgp          Clear BGP information
  chassis      Clear chassis information
  firewall     Clear firewall counters
  igmp         Clear IGMP information
  interfaces   Clear interface information
  ilmi         Clear ILMI statistics information
  isis         Clear IS-IS information
  ldp          Clear LDP information
  log          Clear contents of a log file
  mpls         Clear MPLS information
  msdp         Clear MSDP information
  multicast    Clear Multicast information
  ospf         Clear OSPF information
  pim          Clear PIM information
  rip          Clear RIP information
  route        Clear routing table information
  rsvp         Clear RSVP information
  snmp         Clear SNMP information
  system       Clear system status
  vrrp         Clear VRRP statistics information

  
  user@host> clear
• If you type the question mark in the middle of a command name, the CLI lists possible command completions that match the letters you have entered so far. It then redisplays the letters that you typed. For example, to list all operational mode commands that start with the letter c, type the following:
  user@host> c?

  Possible completions:
  clear      Clear information in the system
  configure  Manipulate software configuration information
  

  
  user@host> c
• For introductory information on using the question mark or the help command, you can also type help and press Enter:

  user@host> help