Wednesday, 8 July 2015

How to receive a million packets per second

Interesting blog post with help with my understanding of the design of a Linux networking stack.

Ostinato - packet crafter/traffic generator

Ostinato aims to be "Wireshark in Reverse" and become complementary to Wireshark.

Toxiproxy - WAN simulator of sorts!

Toxiproxy is a framework for simulating network conditions. It's made specifically to work in testing, CI and development environments, supporting deterministic tampering with connections, but with support for randomized chaos and customization. 

Tuesday, 2 June 2015

Time isnt money

Interesting take on meetings and their true cost "People say "time is money," but they are wrong; time is much more valuable" 

Also found some resonance with Ethan C Banks post in his news letter “The Hot Aisle Newsletter” under “Behind The Tweet”

"when I don't meet my productivity goals by the end of the week, despite an enormous amount of expended energy. It's disheartening to feel mentally exhausted, and yet still have the roughly the same list of tasks I started with."

The plan of action, time to make some changes!

Monday, 2 February 2015

Multigigabit (mGIG) - NBASE-T – IEEE 802.3bz - 2.5 and 5 Gigabits per second over 100m of Cat 5e cable.

Pre standards alliance of companies have created NBASE-T, it can increase network speeds of existing Cat 5e/Cat 6 cables up to 5 Gbps at lengths up to 100m. It seems to have now been resently pickup by the IEEE IEEE 802.3 Next Generation Enterprise Access BASE-T PHY Study Group

Cisco multigigabit will be supported on... (as of 02/02/2015)
Cisco Catalyst 4500
Cisco Catalyst 3850
Cisco Catalyst 3560-CX and possibly the 2960-CX?

Cisco Catalyst 4500 current apparent caveats
“The Cisco Catalyst 4500 product family supports the technology with a new 48-port line card that supports 12 multigigabit switch ports. All the ports, including the multigigabit ports, support POE, POE+, and UPOE. Furthermore, line cards offer significant investment protection by supporting the new multigigabit technology on both types of Cisco Supervisor Engines - Supervisor 7 and Supervisor 8.”

It has been driven by the up coming 802.11ac Wave 2 where the use of extended 5G range will allow for speeds wireless speeds greater than 1 Gigabit.  With AP's currently cabled with CAT5e/6 the cabling back to the NER would become the bottle neck, the cost of upgrading this cable to CAT6a/7 would slow adoption for sure.

What I cant find is a Server/Workstation NIC that will support this technology at this time?  I can see a demand for this with from our power workstation users, as even with port channels of bonded at 1 Gigabit the links limit the flows to the individual channel that flow takes. The cost of replacing floor plate copper is mostly prohibitive at this time this could provide an acceptable compromise if the tech does migrate beyond it current exclusive use for networking hardware?  

Other useful links.....

If you know of any NIC vendors that are planning to support please comment below!

Tuesday, 13 January 2015

40 Gbps & 100 Gbps cabling infrastucture

I have been working on putting in the new Nexus equipment with 40/100 Gbps capability over the past few months.  After searching around today I found this link this page, wish I had found it earlier!  Good summary of technology and infrastructure requirements including Link Loss Budgets.

Friday, 2 January 2015

VRF Lite on Nexus 5600

We are using 5696Q with VRF-Lite with BGP as the routing protocol, stumbled upon this from Ian Pepenlnjak, hes found similar findings so that's good! Anyway not worth rewriting his post either as it will be much better than anything I could put out right now.
VRF Lite on Nexus 5600

Thursday, 1 January 2015

Chistmas Linux Media server build

Over Christmas brake I have been playing with a Linux media server build as I haven't had much chance lately at work to keep my Linux skills up.

Basic Build HP Micro server NL54 + 4 Gig ECC Ram.

OS Ubuntu 14.04 (Should have gone for Mint)
Plex - Media libary + trans coder and DNLA - some fun making profile work for Bravia TV but forums are good.
CatFish File search - cli locate + grep also good!
Thunar File Manager - Batch rename with Regex to assist in getting library clear for Plex.

Graphical System monitoring tool quick Google and found 5 System Monitoring Tools for Ubuntu &I Picked Open System Monitor.

So far so good no real issues and I hadn't got as rusty as I had feared!  Trans coding well even though its only a little AMD 1.5 dual core.