Showing posts from July, 2014

OpenStack and OpenDaylight for Network Professionals

Disclaimer: I wanted to name the post "OpenStack for dummies", but I took a wild guess that CCIEs don't really like to be called dummies, so I "tuned" the title a little bit. You're welcome :)

* OpenStack *
Cisco has nothing to do with them Open Source communities, right? No! In order to get your attention I'll just throw a statement out there - A big part of WebEx runs over OpenStack!!!

Ok, now that I've got your attention - OpenStack is basically a Cloud OS, and it's built as a group of components that use APIs to communicate to each other. Yes, there are many more, but OpenStack is the one that's been dominating the market, and the one that will be in 5 years as popular as Virtualization is today. It's mostly written in Python (yes, Python, and if you want to learn a programming language and you're a Networker - I recommend this one). OpenStack has APIs used for components to be able to "speak" to each other. Centred at I…

Are Cisco Nexus 1000v, CSR 1000v and Vyatta the same thing?

Brief version: No, they are not.

Long version: No, they are not. Nexus 1000v is used for L2 interconnection of the VMs. On the other side, Cisco Cloud Services Router (CSR) 1000v is, in my opinion, a direct competitor of Vyatta /vi:áta/ (acquired by Brocade IN 2012). [Don't make a mistake of underestimating Vyatta, it's a nice and nifty product]. CSR 1000v was introduced by Cisco with the strong message that it will improve the multi-tenancy mechanisms in the Data Center architecture. Why are these improvements necessary, don't we already have VXLAN, NVGRE? Encapsulation can be done using these 3 mechanisms::
- NVGRE (GRE with the key)
- VXLAN (over UDP with proprietary header)
- STT (fake TCP header, so security tools generate alerts, also FW would drop it cause no SYN packets). It can be used between the Hypervisors only.

Well, there are two problems with these solutions. Number 1: None of these 3 has the security, and Number 2: Some clients just want to provide the multi-te…

Network Virtualization vs SDN

SDN (Software Defined Networking) and Network Virtualization, although often in the "same basket", are two different concepts.

Network Virtualization (NV) decouples and isolates "virtual" networks from the underlying physical network hardware. SDN is a concept of separating the Data plane from the Control plane. It does look similar. The NV analogy can be made with the Server Virtualization, which has been the most frequently deployed solution in the Data Centres for quite some time now. In my opinion probably the most important term related to NV is the concept of PROVISIONING. What could this mean in Networking terms? Well, like in the example of Virtual Servers, for example VM machines on the ESXi server, it's the ESXi that provisions the physical resources of the Physical Server or a Cluster to accommodate the needs of the VM. In the same manner, Network needs to provision the VLANs, required Firewall rules, and adjust the IP routing to "welcome" …

CCIE RSv5 Transition Technologies

CCIEv5 started in June, and since my plan is to have the exam prepared for December, I'll first be getting into the New Topics of the Blueprint v5 Lab Curriculum. As you probably know, CCIEv5 is all about virtual equipment with Fast Initial Configuration Reload. If you're a Cisco employee you might take the advantages of IOU, and if not - you always have the GNS3 option. There's no full L2 support on GNS3, so I recommend you to take a deep dive into the following post by INE about the CCIEv5 Hardware.

Since I lost privileges to my old physical rack (I changed the company a few months ago), I'll have to make up my mind soon. I'll probably go with the Virtual Switch, as INE proposed, and sieze the opportunity to broaden my knowledge on the Network Virtualization. In a few years these concepts form a part of Network Engineers everyday life, and you´ve probably noticed that some of my recent posts have been dedicated exclusively to SDN and Network Virtualization techno…


Most of you who've been following my blog in the past, or even most of you who've stumbled upon it by randomly looking for "some Cisco stuff "on Google, are aware that this blog was originally designed as my personal notebook while moving towards the CCIE certification. It's been a while since I started, and I even had an unsuccessful attempt to become a CCIE a few months ago (April 2014). Yeah, yeah, it made me stronger and all... but I was a bit dissapointed because I got the Troubleshooting part which I considered more complex, and failed the configuration part which I was convinced that I was passing. As I'm getting familiar with the CCIEv5 blueprint and planning the next attempt for December, a single 3 letter acronym keeps challenging my motivation. As you probably guessed, I'm talking about the SDN (Software Defined Networking).

[Update, Nov2014] Got my CCIE number, #45370 :)

If you're a Network Engineer, you would have to had lived in an isola…