Ok so my Switch exam is booked, so time to get back on top of blogging my bootcamp notes, which is going to be a bit hard now I’ve left it a few weeks.
So, to start, wiping a switches existing config
erase startup config delete flash:vlan.dat
- 0 = Reserved
- 1 = Default VLAN
- 1002-1005 = Reserved for other media, FDDI, Token Ring….
- 1006-4095 = External VLAN ID
- 4096 = Reserved
- VLAN Trunking Protocol
- VTP Server – Can add/remove/modify VLANs
- VTP Client – Cannot add/remove/modify VLANs
- VTP Transparent – Local VLAN editing only
To configure, set VTP Domain, VTP version, VTP password
VTP Prunning – Limits VLANs to those in use on edge switches,
Layer 2 VSI – Virtual switch interface – used on L2 switches to provide a management IP address
Switch Port States
- Dynamic (Desirable – default setting, Auto)
The default setting on a Cisco switch is Desirable as part of the Dynamic Trunking Protocol (DTP)
- Desirable – Auto = Trunk is formed
- Auto – Auto = No trunk is formed, interfaces are effectively Access ports
Switch – Phone – PC = The phone acts as a mini switch, if a Cisco phone is plugged into a Cisco Switch, it is detected using CDP information, and auto configuration is performed as well as auto power configuration.
Router on a Stick – Create sub interfaces for each VLANs, set IP addresses, which can act as default gateway for the VLAN
Spanning Tree Protocol
PVSTP – Per-VLAN Spanning Tree Protocol – 801.2d Compatible
BDPU Packets used to detect loops
Default Root Priority = 32768
When Tie Break of Root Priority, the lowest MAC address is used. Other switches priority changes to Default Priority + MAC Address or Default Priority + MAC Address + VLAN ID
1 Designated Port per link
1 Root Port per non-root-bridge switch
Each port has a cost depennding on port speed
- 10mb = 100
- 100mb = 19
- 1000mb = 4
- 10000mb = 2
- Blocking = 20 seconds
- Listen = 15 seconds
- Learn = 15 seconds
- Foward = 15 seconds
Total = 50 seconds to transition a port
There isnt actually any times for these, however
Transition achieved in 5-6 seconds.
Priority – Goes up in increments of 4096
To Configure, it is enabled globally
#spanning-tree mode rapid-pvst #spanning-tree vlan 2 root primary or priority No.
STP Versions – IEEE
- 802.1d – STP
- 802.1w – RSTP
- 802.1s – MST/MIST
And this rounds off the notes for Day 6.