VTP is great, in concept, however in the real world I just don't see it deployed to often. The more likely situation is you will be tagging trunks manually, and pruning them manually. The more “real-word” solution to pruning trunks is to just do manual pruning via “switchport trunk allowed vlan x” The command above …
2.1.d (iii) Native VLAN
The native vlan is the untagged vlan on the trunk. When the port is a trunk the native vlan by default is 1, however we can change that with “switchport trunk native vlan X”. The traffic for the native vlan goes out with NO 802.1q header, while tagged traffic on the trunk goes out with …
2.1.d (ii) dot1Q
Section 2.1.d (ii) dot1Q Recall that in section 2.1.c we showed the 802.1q header and discussed all of the fields within, so I won't go over that again. Instead we will discuss choosing the encapsulation on a port. On most newer switches, we only have the option of 802.1q, but older switches also support …
2.1.d (i) VTPv1, VTPv2, VTPv3, VTP Pruning
VTP is cisco proprietary, allows for VLAN propagation across all switches. Vlan Trunking Protocol Min Requirements: All switches use the same VTP domain name (case sensitive) Switches need to be connected via trunks The same VTP pass needs to be used on all members Same version of VTP must be used across a link The …
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2.1.d Implement and Troubleshoot Trunking
Section 2.1.d Implement and Troubleshoot Trunking There was no section to discuss Cisco's Dynamic Trunking Protocol (DTP) so I decided to do it here. DTP allows us to dynamically form trunks on ports where two devices are speaking the DTP protocol. In theory this sounds great, it makes the network plug-n-play. In reality it …
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Cisco Nexus Storm-Control SNMP Trap and EMM Email Script
I'd like to preface this by saying on the nexus platform storm-control by default does not actually errdisable the port (I believe in catalyst it did). We can just have it syslog and generate an SNMP trap. en conf t event manager environment _email_to [email protected] event manager environment _email_server x.x.x.x event manager environment _email_from [email protected] …
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