User Tools

Site Tools


Sidebar

CCNA Notes

Resources

GNS3 - Graphical Network Simulator for Win / Mac / Linux

r/CCNA - CCNA subreddit

notes:various

Various

These items will probably get their own pages at one point.

WAN - Serial


Uses V.35 connector!

Switching


Range / Port Sec


Good things to know:

  • Work on blocks of ranges with a comma separator:
  • Switch(config)#interface range fastEthernet 0/1-5, fastEthernet 0/10-15
  • Clear port-sec macs? Supposedly removes ERR DISABLED states as mentioned in a Crouthamel video. Test this:
  • Switch#clear port-security all
  • Violation Modes:
    • Shutdown:
      • Shutdown the port to ERR DISABLED on violation.
    • Protect:
      • Ignore MAC traffic not configured in port-sec.
      • AKA don't count 3rd machine's traffic if only a max of 2 addresses on the port.
    • Restrict:
      • Same as protect but throws a message to the console.

Switchport Modes


Default switchport mode appears to be dynamic auto.

  • Dynamic:
    • Auto: Will comply with trunk requests
    • Desirable: Will comply AND initiate trunk requests.
  • Trunk: Will act as trunk.
  • Access: Will act as access (no trunking).

Speed / Duplex


Speed and Duplex are auto-negotiated by default. These commands also work on routers. Manually configure them with:

Switch(config-if)#speed ?
  10    Force 10 Mbps operation
  100   Force 100 Mbps operation
  auto  Enable AUTO speed configuration
  
Switch(config-if)#duplex ?
  auto  Enable AUTO duplex configuration
  full  Force full duplex operation
  half  Force half-duplex operation

Re-enable auto-negotiation by removing the configured speed/duplex:

Switch(config-if)#no duplex
Switch(config-if)#no speed

Useful Commands


I'll update these as I come across them.

SW1# show interfaces description
SW1# show interfaces switchport
SW1# show interfaces status
SW1# show port-security interface fa0/1

R1# sh ip route connected OR ospf OR eigrp

OSI Model


Open Systems Interconnection model, 7 layers.

  • “All people seem to need data processing.” – Top to bottom
  • “Please do not throw sausage pizza away.” – Bottom to top.
  • Application
  • Presentation
  • Session
  • Transport
  • Network
  • Data-link
  • Physical
notes/various.txt · Last modified: 2024/04/19 10:36 by 114.119.141.71