Learn Cisco Switching by Doing

Learn how to reduce broadcast domains by creating and naming VLANs, and propagate them across switches using three methods, while configuring trunk and access ports and addressing native VLAN issues.

Learn how to create trunk links between switches to share vlans, using dynamic auto and desirable modes, configure switchport trunk encapsulation, and verify with show interface trunk and status commands.

Explore how vtp propagates vlan configurations across switches through domain names, revision numbers, and server, client, and transparent modes, with practical vlan and trunk demonstrations.

Learn the security enhancements of VTP version 3 over version 2, including single primary server control, encrypted and hidden passwords, and robust revision handling to protect VLAN databases.

Explore how to configure a port channel (ether channel) to bundle multiple links between switches, increasing bandwidth with load balancing using source IP and destination IP and ports.

Learn how the spanning tree protocol prevents loops by blocking and forwarding traffic using MAC address tables, unknown unicast, and broadcast handling, with timer-based VLAN variations shaping the path.

Explore how the spanning tree protocol prevents loops by electing a root bridge and designating ports, selecting root ports by path cost and bridge priority, and blocking redundant links.

Explore how spanning-tree protocol elects the root bridge by adjusting switch priorities and VLAN configurations, and analyze topology changes and route bridge behaviors.

Explore root port election in a two-link switch connection, using path cost and port priority to decide which link forwards and which blocks, while observing listening, learning, and forwarding states.

Configure rapid spanning tree, tune hello and forward delay timers, and enable edge, portfast, uplink fast, and backbone fast options to dramatically reduce convergence time after topology changes.

Explore BPDUGuard, BPDUFilter, and RootGuard to protect networks from rogue switches and superior BPDUs, using error-disabled recovery, BPDU filtering, and designated-port guard rules.

Group vlans into a few instances of the multiple spanning tree protocol to reduce switch workload while keeping correct vlan paths.

Explore first hop redundancy protocols that provide multiple redundant paths at the network edge, covering hsrp, a standard redundancy protocol, and jlp within two-tier topologies.

Configure HSRP basic configuration to provide a virtual gateway across three routers, using a virtual IP and a virtual MAC in a single group, and observe failover.

Learn how preemption and priority govern active and standby roles in Cisco switching, set priority values (default 100, example 120), and enable preemption for automatic failover.

Learn to configure multiple hsrp instances across vlans, set priorities and preemption, and validate active failover when a router goes down for reliable gateway redundancy.

Implement HSRP tracking with IP SLA to monitor ISP links and switch active/standby roles using track objects, preemption, and priority adjustments for seamless failover.

Configure HSRP authentication to prevent attackers from inserting rogue routers by using MD5 with a keychain, syncing standby routers, and validating active and standby states.

Configure HSRP on layer 3 switches by creating VLAN interfaces with IP addresses, enabling IP routing, and setting HSRP priorities and preempt, then verify connectivity with pings across trunked links.

Learn VRRP, the standard virtual router redundancy protocol that enables multi-vendor interoperability; configure active and standby groups, set priorities (with preemption), and apply VRRP on switch interfaces.

Explore GLBP basic configuration to create multiple groups, assign a virtual IP, and balance traffic across forwarders with priority, preemption, and waiting settings.

Configure glbp weighting and load balancing to distribute traffic across routers using weights (1-254, default 100). Apply thresholds with tracking to adjust forwarding and use hash for per-packet distribution.

Configure dot1q tunneling (q-in-q) across isp links, creating a one-queue tunnel on access ports and carrying customer vlans inside isp vlans, with verification steps.

Configure private VLANs by defining a primary VLAN and dependent VLANs in isolated or community modes, assign hosts and promiscuous ports, and map traffic to ensure selective interport communication.

Enable port security on access ports to limit devices per port and enforce allowed mac addresses, with trunk links, sticky learning, and violation modes.

Explore span, remote span (rspan), and er span concepts to copy port traffic to a destination, configure monitor sessions, define source and destination ports, and use vlans for remote span.