Use Azure MFA With Microsoft NPS (RADIUS) Server
Jul20

Use Azure MFA With Microsoft NPS (RADIUS) Server

  KB ID 0001759 Problem I was in a forum last week and someone asked, “Can I enable Azure MFA, on my RADIUS server, to secure access to my switches and routers etc”. It turns out if you want to enable Azure MFA with Microsoft NPS it’s actually quite  simple. So, I’m using RADIUS auth (above) on my NPS server, and it’s simply checking the authenticating user is a member of a domain security group....

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Cisco IOS: Ether-Channel Trunks
Apr08

Cisco IOS: Ether-Channel Trunks

KB ID 0001533 Problem This is a subject that every time I need to create an Ether-Channel I end up checking beforehand, so it’s about time I wrote it up. We are combining two different things, an Ether-channel, (an aggregation of links) and a Trunk (the ability to carry many VLANS). If you are NOT from a Cisco background then you might want to read though the following post first to avoid confusion about the world...

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Cisco Stacking 3750 Switches
Jun16

Cisco Stacking 3750 Switches

KB ID 0001205  Problem You can stack Cisco 3750-X Switches in groups of up to 9 switches, and they can then be managed as one switch. Here I’ve got 2 switches.   Solution Removing 3750-X Switches Stack Configuration One of my switches had already been in a stack, so I needed to remove its stack configuration. It thought it was switch 4 in the stack so I issued the following commands; Switch(config)# no switch 4 provision...

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HP – Switches The IP (or subnet) Already Exists
Apr16

HP – Switches The IP (or subnet) Already Exists

KB ID 0001176  Problem I was changing a clients LAN subnet this week, (dropping the mask from /24 to /16). When I attempted to change the management IP on the clients HP switches this happened; HP2510-24G(config)# vlan 1 HP2510-24G(vlan-1)# ip address 10.0.0.250 255.255.0.0 The IP address (or subnet) 10.0.0.250/16 already exists. HP2510-24G(vlan-1)# At first I though the switch was complaining because the IP was remaining the same, I...

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Cisco IOS – DHCP Helper (DHCP Relay) – IP-Helper Setup
Mar23

Cisco IOS – DHCP Helper (DHCP Relay) – IP-Helper Setup

KB ID 0001168  Problem Cisco documentation calls this a ‘DHCP Relay’, and uses the command IP-Helper, and I usually call this DHCP Helper, just to confuse everyone. To be fair the term DHCP Relay is an industry standard, it’s not particular to Cisco (as you will see later when I Wireshark the traffic). So If you are reading this you have a DHCP server and you want to use it to lease addresses to clients that are on a...

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