Devices

Cisco IOS Supported Commands: Routers

This page lists all IOS commands for routers supported Packet Tracer 3.2.

User Mode commands:

- enable
- exit
- logout
- ping {WORD}
- show
  - access-lists { <1-999> | WORD }
  - history
  - interfaces
    - Ethernet <0-9> <0-0>
    - FastEthernet <0-9> <0-0>
    - GigabitEthernet <0-9> <0-0>
    - Serial <0-9> <0-0>
  - ip
    - access-lists
    - interface brief
    - nat translations
    - route
  - version
- traceroute {WORD}

Enable Mode commands:

- configure
  - terminal
- copy
  - running-config startup-config
  - startup-config running-config
- disable
- enable
- erase startup-config
- exit
- logout
- ping {WORD}
- reload
- show
  - access-lists { <1-999> | WORD }
  - dhcp
  - history
  - interfaces
    - Ethernet <0-9> <0-0>
    - FastEthernet <0-9> <0-0>
    - GigabitEthernet <0-9> <0-0>
    - Serial <0-9> <0-0>
  - ip
    - access-lists
    - interface brief
    - nat translations
    - route
  - running-config
  - startup-config
  - version
- traceroute {WORD}
- write { erase | memory | terminal }

Global Mode commands:

- access-list
  - <1-99>
    - deny
      - A.B.C.D [A.B.C.D]
      - any
      - host {A.B.C.D}
    - permit {same subcommands as deny}
    - remark {LINE}
  - <100-199>
    - deny
      - icmp
        - A.B.C.D
          - A.B.C.D
            - A.B.C.D
              - A.B.C.D
- copy
  - running-config
    - startup-config
  - startup-config
    - running-config
- disable
- enable
- erase
  - startup-config
- exit
- logout
- ping
  - WORD
- reload
- show
  - access-lists
    - <1-999>
    - WORD
  - dhcp
  - history
  - interfaces
    - Ethernet
      - <0-9>
        - <0-0>
    - FastEthernet
      - <0-9>
        - <0-0>
    - GigabitEthernet
      - <0-9>
        - <0-0>
    - Serial
      - <0-9>
        - <0-0>
  - ip
    - access-lists
    - interface
      - brief
    - nat
      - translations
    - route
  - running-config
  - startup-config
  - version
- traceroute
  - WORD
- write
  - erase
  - memory
  - terminal

A PC has one ethernet, one modem, or one wireless port.
The PC may use DHCP to get an assigned IP address, subnet mask, and default gateway from a DHCP server.

A PC can send layer 3 unicast packets and layer 2 broadcast frames (view flowchart). When it does:

- It checks if the port is a WAN port.
  - If the port is a WAN port, then sends the frame out.
  - If the port is not a WAN port, then checks if the destination MAC is specified.
    - If the destination MAC address is specified, then sends the frame.
    - If the destination MAC address is not specified, then checks if the destination IP is in the same network as the PC.
      - If the destination IP is in the same network as the PC, then looks up the MAC address of the destination IP in the ARP table.
      - If the destination IP is not in the same network as the PC, then checks if this PC has a default gateway.
        - If the PC does not have a default gateway, then drops the packet.
        - If the PC has a default gateway, then looks up the MAC address of the default gateway in the ARP table.
      - If a matching entry is not found in the ARP table, then drops the frame.
      - If a matching entry is found in the ARP table, then sets the frame's destination MAC address to the matching entry's.
      - Sends out the frame.

When a PC receives a packet (view flowchart):

- It checks if the port is a WAN port.
  - If the port is not a WAN port, then checks if the frame's destination MAC address is the broadcast address.
    - If the destination MAC address is the broadcast address, then process the frame.
    - If the destination MAC address is not the broadcast address, then checks if the frame's destination MAC address matches the port's.
      - If the destination MAC address does not match the port's, then drops the frame.
- It checks if the packet's destination IP address matches the PC's.
  - If the destination IP address matches the PC's, then it processes the packet.
  - If they do not match, then drops the packet.