Cisco Networking Cheat Sheet

Posted on Dec 3, 2024 in Computers

Cisco Certification Acronyms

CCNA: Cisco Certified Network Associate
CCNP: Cisco Certified Network Professional
CCSP: Cisco Certified Security Professional

Device Acronyms

ASA: Adaptive Security Appliance
FWSM: Firewall Service Module
CSM: Content Switching Module version 3.2 SP2
IPS: Intrusion Prevention System
ACS: Access Control Security

Protocol Acronyms

SNMP: Simple Network Management Protocol
TCP: Transfer Control Protocol
UDP: User Datagram Protocol
ICMP: Internet Control Message Protocol

osi

IOS Commands

Privileged Mode

  • enable: Enter privileged mode
  • disable: Return to user mode
  • enable password <password_here>: Set privileged mode password (less secure)
  • enable secret <password_here>: Set encrypted privileged mode password (more secure)

Setting Passwords

  • enable secret <password_here>: Set encrypted password for privileged access
  • enable password <password_here>: Set password for privileged access (used when there is no enable secret or with older software)
  • Setting password for console access:
    (config)#line console 0
    (config-line)#login
    (config-line)#password <password_here>
  • Setting password for virtual terminal (Telnet) access:
    (config)#line vty 0 4
    (config-line)#login
    (config-line)#password <password_here>
  • Setting password for auxiliary (modem) access:
    (config)#line aux 0
    (config-line)#login
    (config-line)#password <password_here>

Configuring the Router

  • show running-config: Display the running configuration file (RAM)
  • show startup-config: Display the configuration stored in NVRAM
  • setup: Start the automatic setup
  • configure terminal: Enter configuration mode
  • copy running-config startup-config: Save running config to NVRAM (or write memory for older IOS)
  • copy startup-config running-config: Copy config from NVRAM to RAM
  • boot system flash <filename_here>: Specify IOS file in flash to boot from
  • boot system tftp: Boot from IOS file on a TFTP server
  • boot system rom: Boot from ROM
  • copy flash tftp: Copy flash contents to TFTP server
  • copy tftp flash: Restore flash from TFTP server
  • copy run tftp: Copy running config to TFTP server
  • copy tftp run: Restore running config from TFTP server

General Commands

  • no shutdown: Enable an interface
  • reload: Restart the router
  • show version: Display IOS version, uptime, boot info, etc.
  • show clock: Display router’s date and time
  • show history: Display command history
  • show debug: Display enabled debugging information
  • no debug all: Disable all debugging
  • show users: Display connected users
  • show protocols: Display configured protocols
  • banner motd #<Your_message>#: Set/change banner message
  • hostname <router_name_here>: Configure router hostname
  • clear counters: Clear interface counters

Processes & Statistics

  • show processes: Display active processes
  • show process cpu: Display CPU statistics
  • show memory: Display memory statistics
  • show flash: Display flash memory and file information
  • show buffers: Display buffer pool statistics
  • show stacks: Display stack usage for processes and interrupts

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