It’s been roughly five months since I passed the v4 CCIE R/S and I’m starting to hear potential CCIE R/S candidates freaking out about the upcoming changes. I know this feeling all too well, because like many of you I started on v3 and passed on v4. I will never sugar coat this, it’s a royal pain in the arse when the blueprint gets revised, especially if you have been studying (really studying) the current blueprint. That being said, I…
Just wanted to post something quick with reference to my twitter feed. I now use this as my primary means of communicating technology news. Follow @Cisco_East
“It’s gonna take time, a whole lot of precious time, it’s going to take patience and time to do it right child.” “It’s gonna take money, a whole lot of spending money, it’s going to take plenty of money, to do it right” -George Harrison Song: I got my mind set on you I’m pretty sure George had something else on his mind and NOT the CCIE when he wrote that song. I can tell you no other lyrics resonate…
Prologue Hey fellow CCIE’s candidates and networking geeks. Today I want to step deep into the realm of PfR or Performance Routing. First let’s go back in time to the predecessor, Optimized Edge Routing or OER. As crazy as this sounds, OER came out in 2006 with IOS 12.3 . So, technically before all this SDN fanfare, Cisco actually decoupled the control (part of it at least) and data plane with OER/PfR back in the dizay. DID THAT JUST BLOW…
Hello once again! Today I decided to talk about some Cisco innovations around of UCS platform. I’m going to try my best to keep this post high-level and EASY to understand as most things “virtual” can get fairly complex. First up is Virtual Interface Card (VIC). This is Cisco’s answer to 1:1 mapped blade mezzanine cards in blade servers and other “virtual connectivity” mezzanine solutions. Instead of having a single MEZZ/NIC mapped to a specific internal/external switch/interconnect we developed a vNIC optimized for virtualized…
Hi Cisco friends! I had a great question from a customer today regarding failure scenarios and vPC. On the surface, I thought this is an easy one. However, when I really gave it deep thought it really depends on the type of failure. Was the failure on the peer-link, peer keepalive, vPC member port, or the worst case dual active/double failure? Let’s go through some of the failure examples. vPC Member Port Failure If one vPC member port goes down – for…
I got something very cool last week. It came overnight from my good friend Frank in NY. What we have here is a very special privilege folks. It’s a prototype of the Nexus 3548 ultra low latency switch using our custom ASIC called Algo Boost/Monticello. Instead of killing you with all the details I decided to create a video of the un-boxing and special features walkthrough. Enjoy! https://www.youtube.com/user/4g1vn/featured
I recently had one of my customers asked about private VLANs and the benefits/use cases. I thought this was a good opportunity to refresh my knowledge of PVLANs because it was a weak area of mine during my last CCIE lab. What are Private VLANs? The main objective with PVLANs is conserving IP space, but still allowing L2 separation for security purposes. Typically, VLAN design calls for a single IP subnet for each VLAN. Here we are able to create multiple (secondary VLAN/s) VLANs for isolation, but…
It’s been way too long since I posted on my blog. Well, I have been studying for the CCIE Data Center lab and wanted to pass on some very critical information on fabric extender (FEX) configurations. One of the most common questions that our Cisco friends ask me is “Why do I need to create a port channel for the FEX-Fabric links?”. Well let’s dive into the WHY, and then explore the HOW. Let’s first start with a foundation on what FEX is and how it…
IP Services ARP: ARP is the process of resolving unknown L2 (MAC) information FROM known L3 (IP) information. Inverse ARP is learning unknown L3 (IP) information from known L2 (DLCI) information. Proxy ARP, as defined in RFC 1027, was implemented to enable devices that are separated into physical network segments connected by a router in the same IP network or subnetwork to resolve the IP-to-MAC addresses. When devices are not in the same data link layer network but in the…