We have recently set up an IPAM at my workplace, the excellent phpIPAM – https://phpipam.net/ I went through our install and added all our subnets into the IPAM, but to make the data much more useful we wanted to have the VLAN information also: However, I didn’t want to go through by hand, adding each […]
I’ve made a series of videos exploring the Internet Protocol Suite, and how it is used to make a connection to a website. It’s a deep dive into the stack, explaining all the way down to the ethernet frames that a computer sends on the local link.
This script is very simple. It will scan a network range attached to the device it is run from, and will turn what it finds into a list of reservations for the Kea dhcp server – https://kea.readthedocs.io/ You run it something like this, giving it a network range to scan. Then network should be a […]
When trying to find why my ospf configs were not sending the correct costing from Linux -> Cisco devices, I found some useful commands that I thought I would note down for future reference. Linux – Using vtysh My ospfd.conf looks something like this: You can see the costs on linux using the vtysh command: […]
Trying to SSH to a Cisco switch from Ubuntu 20.04 you may get this error: This error is because Ubuntu 20.04 has disabled the SHA1-based key exchange methods after some attacks have been found on SHA1. To work around this issue for Cisco switches you can use the command line argument -oKexAlgorithms=+diffie-hellman-group1-sha1 like this: To […]
I have been trying to find a way to create a regular backup of my Cisco switch’s running-config, so I can store it in my normal backups. However, after searching online I was able to find some tools that were almost there, but nothing that was quite as flexible as I needed, so I wrote […]
I recently decided to move away from using my Wifi access point as a router, and instead use an old my Raspberry Pi 2 as my router. I had a few reasons for doing this: I wanted a more up-to-date device as my internet facing box. My Wifi AP hasn’t received any firmware updates in […]