MSTP
MSTP All switches need this: spanning-tree mst configuration instance 1 vlan 1-3 instance 2 vlan 4-6 instance 3 vlan 7-9 Root Needs this: spanning-tree mst 1-3 root primary
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Spanning Tree
Cisco PVST+ 802.1d Root Bridge Elect Root Bridge -> Lowest Bridge ID Bridge ID -> Priority + MAC All ports on the Root Bridge are Designated ports and are in a Forwarding State. Root Bridge is the Reference Point for everyone else. Each switch in the network looks for the best path to the root bridge. Decision is made based on the path cost. If the path cost is the same Port ID breaks tie. All other ports towards the Root Bridge are put in Blocking/Alternate state. Path Cost Ethernet = 100 Fast Ethernet = 19 Gigabit = 4 10 Gigabit = 2 Port States - Convergence takes 50 seconds Disabled Blocking - 20 seconds Listening - 15 seconds Learning - 15 seconds Forwarding Network Changes BPDUs - Hello timer is sent every 2 seconds TCNs are sent up stream to each device notifing the switch of a change in the topology. TCAs are sent back down stream to acknowledge the changes. This is done untill the TCN reaches the Root Bridge. Rapid PVST+ 802.1w Root Bridge Elected the same way as 802.1d P...
Going to start studing for my CCIE Lab
Well the time has now come to complete the long journey of obtaining my CCIE. If you have no idea what this is you can go to http://www.cisco.com/go/ccie. At the time of this blog there are only about 6124 CCIEs in North America. I have taken the written exam and scored a 94 percent. This qualifies me to schedule the LAB. I have all of my own gear to lab on. I have purchased Workbooks Volume I, II, and III from internworkexpert.com and will be using these to prepare for my lab. My friend David tells me I need to read 3 books to pass the lab and since he said I would have to read them to pass of course I want to try to pass without reading them. I however decided it might take me 2 attempts to pass the lab if I do not read these books. I broke down and bought the 1st of the 3. This book is called Bridges, Routers and Switches for CCIEs. My plan is to read 1 chapter a day. I will start being accountable today. I am on Chapter 3 page 89. Today I will have finished chapter 3 ...