2.1.f (i) PVST+/RPVST+/MST 802.1D Classic STP and PVST+ Note that when focusing on legacy spanning tree, we are actually focusing on per vlan spanning tree + which runs classic STP per vlan. We don't actually have the option of 802.1D or classic spanning-tree in our switches. Before we begin you should know what a burned …
2.1.f Implement and Troubleshoot Spanning-tree
2.1.f Implement and Troubleshoot Spanning-tree In this top most section I'd look to go over the Bridge Protocol Data Unit (BPDU) which is the building block of spanning-tree. Let's go in-depth on the headers, their values, and their differences in version iterations. 802.1D Spanning Tree / PVST+ BPDU You should utilize my anki notes that …
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2.1.e (iv) Etherchannel misconfiguration guard
Etherchannel misconfiguration guard is a feature enabled by default on all switches, if you wish to turn it off (crazy) you may use no spanning-tree etherchannel guard misconfig or turn it back on with the spanning-tree etherchannel guard misconfig To verify: show spanning-tree summary When one side is misconfigured for a static etherchannel the …
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2.1.e (iii) Load-balancing
2.1.e (iii) Load-balancing Flows can become polarized (like CEF polarization) to a specific link if ther flow is not classified as diverse. So depending on the etherchannel load balancing hashing algorithm, we might get polarization. By default Cisco devices just hash the flow based on the source mac address, which is susceptible to polarization, thus …
2.1.e (ii) Layer 2, Layer 3
2.1.e (ii) Layer 2, Layer 3 Etherchannels are independent from their port types. Meaning they can be access ports or trunks, it does not matter. You can negotiate an etherchannel between a L2 (switch) and a L3 device (server/router/whatever). Or you can negotiate one to another switch L2 to L2. Note the order of operations …
2.1.e (i) LACP, PAgP, manual
2.1.e (i) LACP, PAgP, manual Configuration: When configuring a channel group we have the options of LACP, PAGP, or just ON (static). Here's an example of ports g0/1-2 in a port channel: en conf t int range g0/1-2 channel-group 1 mode <active | auto | desirable | on | passive> These obviously do different things: …