This post is a collection of other random information, config examples etc. that I’ve cobbled together in preparation for the SWITCH exam: AAA TACACS+ config enable AAA gloablly on the switch switch# conf t switch# (config) aaa new-model configure the switch with the IP of the TACACS+ server switch(config)# tacacs-server host 10.10.10.150 configure the encryption used […]
So…..with my SWITCH exam scheduled for a couple of weeks from now, it’s time to knuckle down for some serious prep work. This is going to be a mixture of reading, lab exercises and practice questions. To give this some structure and ensure I cover everything off I thought it would be a good idea to […]
Hierarchical Network Design predictable behavior low maintenance high availability recover from failure and topology changes in a pre-determined manner scale to support future expansion and upgrades design around traffic flows rather than a particular type of traffic keep end users at consistent distances from resources cisco approach enables designers to organize the network into distinct […]
InterVLAN Routing requires that routing be enabled for the layer 3 protocol – eg. IP Routing requires static routes or a dynamic routing protocol by default every port on most catalyst switch platforms is layer 2, and on 6500’s every port is layer 3 by default to determine the mode a switch port is in: […]
Protecting The Spanning Tree Protocol Topology There are 2 conditions that can occur to disrupt the loop free topology even when STP is running: BPDU’s suddenly being received on a port that shouldn’t be receiving them – can result in unexpected re-convergence results BPDU’s suddenly stop being received on a port that should be receiving them […]
STP Root Bridge Root bridge location should be determined as part of the design process. Adjustments to the STP configuration can be made for things like using redundant links to load balance in parrallel, or configuring STP to converge quickly and predictably if a major topology change occurs. note – if STP has […]
Overview defined in IEEE 802.1D. provides network link redundancy, so that a layer 2 switched network can recover from failures without intervention in a timely manner. solves the problem of bridging loops (forwarding a single frame around and around between two switches) enables switches to become aware of each other in order to negotiate a […]
Rapid Spanning Tree Protocol IEEE 802.1D – original STP, topology change takes 30 seconds before port goes from blocking to forwarding IEEE 802.1w – RSTP, much faster convergence, as with STP can be applied as a single instance or multiple instances by using RSTP with Cisco’s own PVST+, resulting in Rapid PVST+. Can also be […]
Switch Port Aggregation with Etherchannel 2 to 8 links of 100mb, 1gb or 10gb can be bundled as one logical link of Fast Etherchannel (FEC), Gigabit Etherchannel (GEC), or 10 Gigabit Etherchannel (10 GEC) respectively, giving a full duplex bandwidth of up to 1600mbps, 16gbps or 160gbps. There are no spanning tree issues […]
Static VLANs Port-based membership. End user devices are members of VLANs based on the physical switchport they are connected to, and are not aware of which VLAN they are in. Ports are assigned to VLANs by an administrator and the port receives a Port VLAN ID (PVID) that links it to a VLAN number. Switchports […]