Boudewijn Plomp

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My first FlexPod! (Part 4 – Quality of Services)

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This is part 4 of the following blog series:

Quality of Services:

I hope you enjoyed reading part 1, 2 and 3. As explained Cisco UCS is a converged infrastructure. A converged infrastructure uses less cabling and allows you to configure vNIC’s and vHBA’s as an abstraction layer on top of the physical infrastructure. This offers flexibility and has some benefits. It also adds an important requirement, which is QoS (Quality of Services). Without QoS, any type of traffic could saturate all available bandwidth resulting in slow network or storage performance. Which could potentially make your compute platform unstable. It is important that each type of traffic can consume as much bandwidth as possible when needed, but when the network gets congested each type of traffic gets a fare share of bandwidth, shaped by a pre-defined weight (%).

The nice thing is, Cisco UCS fully supports QoS. In fact, it is an absolute requirement which is easy to configure. QoS is not only used for traffic shaping, it is also used to handle certain type of traffic differently. Like storage traffic (especially Fiber Channel traffic) needs to be lossless (without packet drops). And you might want certain type of traffic (like iSCSI traffic) to use a different MTU packet size (e.g. Jumbo Frames with MTU 9000).

With this blog I am not going to explain QoS in technical detail. I will give you some links to technical resources that were useful to me. And I will explain what you can and need to configure in UCS Manager. [Read more…]

My first FlexPod! (Part 3 – Hardware Configuration)

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This is part 3 of the following blog series:

Hardware Configuration:

If you have read part 1 and part 2 you should now know a bit more about Cisco UCS and our hardware combination. In this part I will share you my hands-on experience with Cisco UCS. Note I am not going to explain how I configured the Nexus switches, Catalyst switches, ASA firewalls and NetApp storage devices. With this blog I want to focus on Cisco UCS in general. [Read more…]

Sender ID Framework (highly recommended)

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As we all know, e-mail is a very important part of our daily lives. At least, during our daily job. When we talk about e-mail it is clear that the number of SPAM messages is increasing. Apart from the fact that SPAM is annoying, it is also a potential threat. By means of SPAM; spoofing and phishing is often used to steal someone’s identity. It can harm the reputation of the domain owner. SPAM can also consumes unnecessary bandwidth and affect overall performance of a mail server.

Anti-SPAM:

Of course we often use Anti-SPAM filters. A disadvantage of Anti-SPAM is that it sometimes marks e-mail messages as SPAM while it isn’t, with the risk losing legitimate e-mail. And every now and then an unwanted SPAM message gets through. This is why we constantly have to be kept up-to-date with Anti-SPAM definitions. Fortunately, more and more is done in terms of legislation against SPAM. But the harder we fight against SPAM it will never solve the problem entirely.

If you zoom in on SPAM then there is something that is not so noticeable; it’s always the receiver that needs to protect themselves against SPAM. Right?

The fact is, the owner of a domain can definitely do something about it. A very good method is using the Sender ID Framework (SIDF). From my own experience, I can highly recommend Sender ID Framework! It is very easy to apply, and it is totally free. Unfortunately, the Sender ID Framework is somewhat underexposed. This is a shame, because it works very well. With this blog I hope to bring the Sender ID Framework to your attention. Are you an administrator of an e-mail server, are you responsible for inbound and outbound communication for you company or are you using e-mail in other way, then I highly recommend you to read this blog. [Read more…]

Troubleshoot NICs (left behind in registry)

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Symptoms:

At customers I have noticed that sometimes problems occur with network interfaces in Windows, either physical or virtual network interfaces. Having one or more of the following symptoms:

  • A static IP Address cannot be used because (accoring to Windows) it is already in use. But there is no sign of a NIC with that specific IP Address.
  • A static Default Gateway on the TCP/IP properties of your NIC is lost after reboot or directly after you apply the TCP/IP settings.
  • The label “Local Area Network 2” or “Ethernet 2” cannot be renamed to “Local Area Network” or “Ethernet” because (according to Windows) that name already exists.
  • A network interface is detected and shown in Device Manager as <interface-name> #2, whereas it is the only interface.

These symptoms occur when settings are left behind in the registry. Which is often caused by human error, incorrectly removing a NIC (Network Interface Card) interface, or using an OS image on another machine. Of course there is no one to blame, what seems so simple is sometimes overlooked. Troubleshooting these symptoms can take a lot of time. But in fact they are quit easy to solve. With this blog I hope to make you aware about what you should (not) do when removing or re-adding a NIC. And if you encounter such symptoms, how to solve it.  [Read more…]

My first FlexPod! (Part 2 – Hardware Overview)

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This is part 2 of the following blog series:

Hardware Overview:

If you have read part 1 you should now know a bit more about a Cisco FlexPod. As mentioned, a Cisco FlexPod is a reference architecture and can be combined with any hardware you want, which makes is very flexible and scalable. With the budget at that time we started with the following hardware infrastructure:

Cisco FlexPod (hardware overview)

Altough this pictures might look nice to you, it is quite useless if you don’t know what it is all about. So I have to give you some detailed information about the hardware and it’s capabilities. I am afraid this is going to be a long blog. But hey, let’s go for it! 🙂  [Read more…]