IEEE OUI address (MAC address) allocation
I've recently noticed that it is becoming more and more common to see 'weird' MAC addresses, i.e. MAC addresses which do not start with numbers 00. Previously it was very easy to spot automatically mentally software defects which would cause strange MAC addresses to appear, it has helped me to diagnose several issues in the past. We've now beginning to lose that advantage, as IEEE has started to allocate MAC addresses quite randomly across the address space.
I emailed to IEEE and asked what was the motivation and perceived advantage in doing this change and reply was quite simply 'We changed our allocation methods to prevent vendors using unregistered mac addresses.'. OUI costs 1650USD one time fee, but IEEE appears to be concerned that some vendors choose not to pay it, instead allocate themselves OUI somewhere far in the address space, effectively thinking they are getting free OUI with little to no possibility of overlap. It would be curious to know if this instance who wants to save 1650USD would care about this slightly changed climate, I personally doubt the change while good-willed is completely ineffective and the slight operational benefit serial assignment had is lost. (/me starts Continue reading
Resolving SNMP OID in snmpbulkwalk and tshark
This isn't exactly esoteric science but at least for me it has been too hard and I've rather looked up OIDs manually, which makes little sense in the long run.
NET-SNMP
First of all, you probably want to set system wide version and community, so you never need to type them on snmpbulkwalk
# cat /etc/snmp/snmp.conf
defVersion 2c
defCommunity supersecret
#
Also I prefer to have vendor MIBs for my user only, as I might want to load lot of them, which will give lot of warnings, which other users may not want.
# cat ~/.snmp/snmp.conf
mibs +ALL
#
Instead of +ALL you could add named MIBs which to load, ~/.snmp/mibs/ directory is searched for users MIBs. You could start by uncompressing ftp://ftp.cisco.com/pub/mibs/v2/v2.tar.gz there. Now you should be able to snmpbulkwalk router by giving just its name, no version, no community and OIDs should be resolved.
WIRESHARK/TSHARK
To me this is more useful than net-snmp, to lab what type of traps router would send and in what situation. For some weird reason wireshark/tshark doesn't honour net-snmp settings, but needs its own settings.
# cat ~/.wireshark/prefefences
name_resolve: mtC
name_resolve_load_smi_modules: TRUE
snmp.display_oid: Continue reading
Ticket #13 – Republished
I am reposting here Lab 13, which was published on ccieflyer.com. Next ticket, Ticket 14, which will be about BGP, OSPF and telnet will be published on CCIEFlyer.com, then it will be republished here again. ...However, its not working, as no router can ping BB1 from it's Lo0.Cisco Network^WLive! 2011 Las Vegas Conference report, part 2
Part 2... where we take a stab at the food served one gets for 1700 (thereabouts) bucks at conferences.Breakfast
When: every day 0700-0800 (one hour only)
What's available: cereal + milk, sugary doughnuts, croissants, bottles of juice or soda pop.
Grade: C-. The time could be longer and the stuff available isn't exactly from the food pyramid either. I did this once and the rest of the time paid for hotel breakfast which was excellent.
Lunch
When: 11-13 (or thereabouts)
What's available: different menu every day, lots of choices, veggie, meat, fish, salad, etc. Drinks water, icea tea, lemonade, soda pop
Grade: B+. Certainly isn't a Michelin restaurant experience but seemed nutritious enough, wasn't all greased up, there were plenty of choice each day (beef/fish, fish/chicken, chicken, etc.) and always a veggie choice.
Snacks
When: around 1000, around 1400
What's available: granola bars, sugary coated doughnuts, coffee, tea, water, some fruit, juice, ice cream, ... depending on the day
Grade: B-. Lots of choice. Sometimes the snacks went quite quickly so I didn't get some on a few days when the presentation ended later than planned. Either there were too little snacks to start with or some people stocked Continue reading
TS workbook dynamips files – BETA
If you are an owner of the TS workbook and want to use dynamips, please contact me offline to participate in the BETA.Android & Eclipse Troubles
Setting up a new Android Development Environment in Eclipse? Having troubles? Maybe one of these two solutions will help: PROBLEM #1 I recently re-imaged my PC and decided to build my Android Development Environment from scratch. Some recent modifications to my eclipse installation messed it up so I cut my losses and started over again. This time around, I noticed that Eclipse Helios was available for download, and not only that, it was the first version of Eclipse to offer a 64-bit version of the IDE for windows.Android & Eclipse Troubles
Setting up a new Android Development Environment in Eclipse? Having troubles? Maybe one of these two solutions will help: PROBLEM #1 I recently re-imaged my PC and decided to build my Android Development Environment from scratch. Some recent modifications to my eclipse installation messed it up so I cut my losses and started over again. This time around, I noticed that Eclipse Helios was available for download, and not only that, it was the first version of Eclipse to offer a 64-bit version of the IDE for windows.Android & Eclipse Troubles
Setting up a new Android Development Environment in Eclipse? Having troubles? Maybe one of these two solutions will help: PROBLEM #1 I recently re-imaged my PC and decided to build my Android Development Environment from scratch. Some recent modifications to my eclipse installation messed it up so I cut my losses and started over again. This time around, I noticed that Eclipse Helios was available for download, and not only that, it was the first version of Eclipse to offer a 64-bit version of the IDE for windows.Ticket #13
Ticket #13 is published under the CCIE Flyer. Click here for direct link. Enjoy!Apps of Empowerment
This will be a short one (cough, I’m at work, cough) but I gotta share these links. Downloadsquad.com shares some great links, but these stories in particular give lists of apps that any computer-savvy person must at least be aware of. Before you go googling to download some shoddy software that may or may not do what you want it to, check out these lists first: http://www.downloadsquad.com/2008/09/02/24-killer-portable-apps-for-your-usb-flash-drive/ http://www.downloadsquad.com/2008/10/01/24-great-open-source-apps-for-admins-and-technicians/ http://www.downloadsquad.com/2009/05/18/40-great-open-source-apps-and-games-to-trick-out-your-new-windows/ Again, thanks to Downloadsquad.Apps of Empowerment
This will be a short one (cough, I’m at work, cough) but I gotta share these links. Downloadsquad.com shares some great links, but these stories in particular give lists of apps that any computer-savvy person must at least be aware of. Before you go googling to download some shoddy software that may or may not do what you want it to, check out these lists first: http://www.downloadsquad.com/2008/09/02/24-killer-portable-apps-for-your-usb-flash-drive/ http://www.downloadsquad.com/2008/10/01/24-great-open-source-apps-for-admins-and-technicians/ http://www.downloadsquad.com/2009/05/18/40-great-open-source-apps-and-games-to-trick-out-your-new-windows/ Again, thanks to Downloadsquad.Ticket #12 – Republished
I am reposting here Lab 12, which was published on ccieflyer.com. Next ticket, Ticket 13, which will be about BGP, will be published on CCIEFlyer.com, then it will be republished here again. ...For more mini labs, have a look at the mini labs page.IPv6 Deployment Practices and Recommendations
Communications technologies are evolving rapidly. This pace of evolution, while slowed somewhat by economic circumstances, still moves forward at a dramatic pace. This is indicative to the fact that while the ‘bubble’ of the 1990’s is past, society and business as a whole has arrived to the point where communications technologies and their evolution are a requirement for proper and timely interaction with the human environment.
This has profound impact on a number of foundations upon which the premise of these technologies rest. One of the key issues is that of the Internet Protocol, commonly referred to simply as ‘IP’. The current widely accepted version of IP is version 4. The protocol, referred to as IPv4 has served as the foundation to the current Internet since its practical inception in the public arena. As the success of the Internet attests, IPv4 has performed its job well and has provided the evolutionary scope to adapt over the twenty years that has transpired. Like all technologies though IPv4 is reaching the point where further evolution will become difficult and cumbersome if not impossible. As a result, IPv6 was created as a next generation evolution to the IP protocol to address these issues.
Storage as a Service – Clouds of Data
Storage as a Service (SaaS) – How in the world do you?
There is a very good reason why cloud storage has so much hype. It simply makes sense. It has an array of attractive use case models. It has a wide range of potential scope and purpose making it as flexible as the meaning of the bits stored. But most importantly, it has a good business model that has attracted some major names into the market sector.
If you read the blog posts and articles, most will say that Cloud Storage will never be accepted due to the lack of security & accountability. The end result is that many CISO’s & CIO’s have decided that it is just too difficult to prove due diligence for compliance. As a result, they have not widely embraced the cloud model. Now while this is correct, it is not totally true. As a matter of fact most folks are actually using Cloud Storage within their environment. They just don’t equate it as such. This article is intended to provide some insight into the use models of SaaS as well as some of the technical and business considerations that need to be made in Continue reading
Troubleshooting workbook promotion
I got some good news! For a limited time, the troubleshooting workbook price is discounted to 200$. You can purchase the workbook here.Ticket #12
Ticket #12 is published under the CCIE Flyer. Click here for direct link. Enjoy!Arista 7500: the Fastest and Greenest 10 Gigabit Ethernet Switch
We are witnessing a major shift from traditional enterprise data centers to much larger warehouse-scale cloud data centers. This is driven by the economics of scale and the benefits of cloud computing, and is happening for both for public and private clouds.
These large data centers need a much higher performance networks that bears little resemblance with traditional enterprise networks. A cloud data center network needs to interconnect many thousands of servers with predictable bandwidth and low-latency.
Our original goal was a switch that could connect 10,000 servers with a simple, 2-stage network, that would deliver predictable Gigabit performance for each server, and do this at a price point that is compatible with web and cloud business models. Just to be clear, such a network requires 10 Terabits/second throughput (10,000 x 1 Gbps), active-active load-sharing redundancy to avoid any single point of failure, and the ability to run 24×7 since there are no maintenance windows in the cloud world.
I am very pleased with the product that resulted from this development, the Arista 7500 data center switch. It turned out really great, even better than we originally anticipated.
The Arista 7500 switch is the highest throughput 10G Ethernet switch in Continue reading