network performance

OpenStack network mystery: How 2 bytes cost me two days of trouble

Once upon a time, I set up an OpenStack cluster and experienced some strange connectivity problems with all my OpenStack instances. It was the perfect opportunity to learn more about OpenStack, perform a head-long deep dive into Neutron, and update my network troubleshooting skills. The preliminaries I set up my OpenStack cluster on 6 Dell OptiPlex 7040 machines, 1 router, 1 managed switch, and 1 unmanaged switch. True, this is not the usual … read more

Defending the Network: Flow vs. Wire Data

In recent months, at multiple customers, I’ve had the opportunity to observe shockingly similar problems that follow an unfortunately common scenario: There is a perceived site issue A war room or incident is started The network is quickly thrown under the bus Why? Because the complaints are only coming from one site; therefore, it MUST be a network issue This predicament results in the network team reeling backward as they scramble … read more

Because you can’t always blame network operations…or the network!

What’s your most memorable “blame the network” anecdote? If you’re in network operations, you will likely have many from which to to choose. After all, doesn’t the network always get blamed first? To be fair, other teams often feel the same. Citrix and VMware admins have alternately been touted as “the new network guy,” and as this Dilbert cartoon suggests, the stigma can impact almost anyone in IT. If you’re on the … read more

Defending Network Performance with Packet Level Detail

My favorite war room accusation is: “It’s always the network at fault!” Whether you’re the one taking the blame or the one pointing the finger likely has everything to do with which seat you occupy in that war room. I suppose that comes with the territory, because at the same time there seems to be a consensus that the network is vital to understanding that holistic “Big Picture” on how … read more