L2 fundamental Flashcards
Vlan 1
Default and Trunk=Native
Ext. Range Vlans
-1006-4094
-VTP Trans Mode
802.1Q
-Trunking protocol
-Insert tag in frame
-dot1q
DTP
Dynamic trunk protocol
VTP
Vlan trunking protocol
Encap
Encapsulation protocol
STP version
Classic: 802.1D-ieee
Default: 802.1w- rapid-pvst+
802.1s - MSTP
STP process
- Root bridge elected
- 1 Root port elected
- Each link has 1 designated port elected
- Leftover is non-designated; i.e blocking
Root bridge
Lowest BID=Priority + VLANID + MAC address
All ports are designated port
Lower=Better
STP tools
Port Fast:
BPDU Guard= err- disables port when an other switch/device tries to take over STP
Root Guard=no other device can come and take root bridge role
Loop Guard=stop normal convergence process
MST
-Multiple Spanning Tree
-802.1s
- exact number of topologies
Spanning-Tree mode config verify
MST region name
MST revision number
Instances>Vlan
LACP
Link Aggregation Control Protocol
Active/Passive on both sides
CAM
Content Addressable Memory
BPDU
Bridge Protocol Data Unit
Contains Root ID
Port States 801.1D
Find
Listen: listening for BPDUs
Learn: leaning for BPDUs
Blocking: blocks all traffic except for BPDUs which it only receives
Disable: Int shut down
STP Timers
Hello: 2 seconds
Fwd Delay: How long between listening and learning state; 15 seconds*2
Max age: 20 Sec
50 seconds= failure
Rapid PVST+
802.1w
Uses P+P negotiations instead of timers
All switches send BPDUs
Different port types
TCN doesn’t need root to forward
TCN receives=flush MAC table
TCN
Topology change notifications
Port States 802.1W
Fwd.
Learn
Discarding= Listening, Blocking and Disable. Receiving BPDU, not sending them.
Port type Edge ports
Skips 30s and TCN
Port type Network ports
Bridge assurance
