Cisco STP forward-time command trick

This is more a topic for exams, like Cisco CCIE, but also it can appear in real-world environments.

Consider the following simple topology:
Simple L2 topology

SW1 is the spanning-tree root bridge for all VLANs. Imagine that you have a request which ask you that when a port becomes active, no matter of VLAN, it should wait 10 seconds until it transition to forwarding state.

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EtherChannel over 802.1q Tunneling

Consider the following topology:
EtherChannel over 802.1q Tunneling Topology

We have one Customer with two distributed locations (SW1, R1 and SW2, R2) connected over Provider backbone. What we want to create is something like this:

EtherChannel over Provider L2 cloud

If Provider support 802.1q and L2 tunneling we can achieve a nice Etherchannel between our 2 remote locations with direct CDP visibility. Also STP and VTP is supported, just like when these SW1 and SW2 switches are directly connected.

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CCIE Home Lab, what to do when your router has too little Flash space for IOS

CCIE Home Lab, what to do when your router has too little Flash space for IOS

I already explained in an older post my home lab for CCIE preparation. My BB1-BB3 routers are Cisco 2600 series and the rest of R1-R6 are emulated with Dynamips. The only problem is that one of the C2600 has too little Flash space to hold the required IOS. Memory is sufficient, but Flash not.

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