Replacing a failed Nexus 5K and some bugs.

Being given the task of replacing a failed Nexus 5596UP (no console output, powers up with fans but no lights except amber on the mgmt. module at the back), I quickly ran into some annoying problems trying to configure the FEX uplinks before actually racking it and plugging it in. I wanted to get as much config done beforehand as possible to minimize any interruptions – I was also a bit nervous as this unit was in the VPC primary role before it failed.

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System Messages and Recovery Procedures for the Cisco Nexus 3000 Family

This chapter includes system messages for the Cisco NX-OS Nexus 3000 family of switches. The messages are listed in alphabetical order by the system facility that produces them. Within each system facility section, messages are listed alphabetically by severity and mnemonics. Each error message is followed by an explanation and a recommended action.

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Private VLAN’s and PVLAN Edge

Overview of attacks & countermeasures

  • IP spoofing – IP source guards, PACL
  • STP Spoofing – BPDU guard, Root guards
  • MAC Spoofing  – Port Security , Static CAM table entries
  • DHCP Server Spoofing – DHCP Snooping
  • ARP Spoofing – ARP inspection (ASA + IPS )
  • VLAN Hopping – Disable auto DTP *
  • CAM Floods – Port Security , 802.1x
  • DHCP Starvation – DHCP Rate limiting

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What Cisco Output Commands Are In A “Show Tech” On The Nexus 5000?

Have you ever wondered what commands were actually in a “show tech” on the Nexus 5000? Well, I did. There seems to be a lot of info in there, and there really is. I compiled a list of commands that a show tech runs on a Nexus 5000 and have listed them below. Enjoy!

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