ifconfig.it

Where the vNIC meets the Network

War stories - Network changes tools

Every time I manage a change to a customer network I have a chance to taste the many shades of possible IT Operations maturity levels. I collected some best practices over the years about how to reduce risk and speed-up the change and testing process. I’ll share some in this post. Improvements and suggestions are welcome in the comments of the post or on my Twitter account.

War stories - Network changes tools

Every time I manage a change to a customer network I have a chance to taste the many shades of possible IT Operations maturity levels. I collected some best practices over the years about how to reduce risk and speed-up the change and testing process. I’ll share some in this post. Improvements and suggestions are welcome in the comments of the post or on my Twitter account.

Network topology validation with CDP and Python

As most IT professionals I usually configure network devices in a lab environment before the actual installation at customer site. I try to limit the installation as much as possible to a simple box moving process, spending most of the change window in a previously defined validation process. In this particular case I deal with a data center core network that includes 8 Nexus 9k switches configured in 4 VPC pairs and a bunch of links between them.

War stories - The Docking Station

This story starts with a phone call at night. If you worked in IT long enough you know what it means. Customer’s HQ network is down and since the day before I’ve replaced a pair of data center switch in a remote site I’m somehow involved based on the well-known principle “last one who made changes is responsible”. I state that all the facts took place with my telephone support, without any remote access to the machines.

Telnet over Internet

A couple of days ago Cisco released a Security Advisory. No big deal so far, level was informational so I didn’t read it right away. Title is impressive: Cisco Best Practices to Harden Devices Against Cyber Attacks Targeting Network Infrastructure so i read it during a lunch break just to be aware of the contents. Management sessions to network devices provide the ability to view and collect information about a device and its operations.