In this fairly short post, id like to address a topic that came up on IRC (#cciestudy @ freenode.net). Its about how you select a route thats being redistributed into an OSPF NSSA area and comes into the OSPF backbone area 0.
For my post i will be using the very simple topology below. Nothing else is necessary to illustrate what is going on.
First off, id like to clarify a few things about what takes place when redistributing routes into an NSSA area.
What happens is that you have an external network, 4.4.4.4/32 in our example. This is _not_ part of the current area 1. When this network is being redistributed into area 1, its forwarding address will be set to the highest active interface of the redistributing router in the area (R4 in our case). The highest interface in the area local to the router is Loopback100 with an address of 44.44.44.44/32.
*A reader noted that a loopback address will beat a physical interface even if it has a lower address. This is true and goes for OSPF in general. Thanks!
Lets verify the configuration on R4 and the result of Continue reading
Very often in our lives we are fully focused on what is going to happen in the
future. We rarely look back at what we have done and how we got to where we
are now. People that know me, know that I’m a very focused person that is always
looking to improve my skillset.
In July of 2010 I decided that I wanted to become a CCIE. I was a CCNP at that
time and I was working in a role where I did 2nd level support. I decided that
I wanted to blog to keep my notes for the CCIE online. I wrote my first blog
post on July 16, 2010. Today on August 16, 2014, almost four years later I passed
400k views on the blog. It’s been an amazing journey and here is a look back at
what has happened since then. This post is meant to be inspirational, to see
what can be accomplished in four years if you put your heart to it, please don’t
take it as boasting :)
For my CCIE studies I used INE workbooks, I decided that it would be good practice
to answer questions on their forums to keep Continue reading
CPUG, a Check Point user forum, is near death. The owner has been forced to get rid of it, but rather doing a graceful handover, it has been shut down pending a possible sale. This is a great shame, and it highlights the risks of contributing to a forum controlled by a single person.
CPUG.org started out as an independent Check Point forum in around 2005. It was seeded with Phoneboy’s original FW–1 FAQs, and quickly became the premier independent source of Check Point information. If you had a Check Point problem, chances were you could get a quick answer there.
I used to do a lot of Check Point work, and so I knew a fair bit about it. I had the time, knowledge, and the desire to help the community, so I got involved with CPUG, and became a top contributor. I put a huge amount of effort into it over the years, and hopefully I helped solve a few people’s problems. I have moved away from contributing recently, for various reasons.
At its best, the forum was a fantastic resource, where many of the smartest people were working to help solve the trickiest issues. It became Continue reading
But no matter how much you spend and how lofty the promises of the vendor, hardware does fail. And because systems do inevitably fail, redundancy is your friend when it comes to minimizing the impact of a failure. Systems have redundant power supplies and fans. The connections between systems are redundant. The systems themselves are redundant. And in some cases entire data centers are redundant in different geographical locations.
With the release of Cumulus Linux 2.2, there is now an open solution for redundant layer 2 top of rack, or ToR, switches. No longer will a single ToR switch failure take out your entire rack of servers. This is because Cumulus Linux 2.2 includes Host-MLAG, which allows servers to connect to redundant ToR switches using active-active LACP bonding. Some of the advantages of Host-MLAG include:
A year ago I asked “Has HP Abandoned Operations Manager?” There had been no significant development for a long time, and the signs were that HP was moving away from OM to OMi.
Last week HP made a move that confirms my original thinking: It’s dead (it just doesn’t know it yet). HP released a Customer Letter announcing an extension to the “End of Committed Support” date, from December 31, 2016 to June 30, 2018:
HP is committed to providing the highest level of customer care to you while you determine your future strategy for your HP Operations Manager for Windows 9.0x & HP Operations Manager for Windows Basic Suite 9.1x products.
(emphasis mine)
That’s right, no new version announcement, just extending support for the current version. Implication: no new versions coming any time soon.
HP has released patches OMW_00185 and OMW_00187 for OMW 9.0. These include the usual bugfixes, and these enhancements:
"somebody who tries to provoke an emotional reaction"The way to stop trolls is to grow up and stop giving them that emotional reaction. That's going to be difficult, because we have a nation of whiners and babies who don't want to grow up, who instead want the nanny-state to stop mean people from saying mean things. This leads to a police-state, where the powerful exploit anti-trolling laws to crack down on free-speech.
Carenection is where I currently work as the Senior Network Architect. We are looking for a Junior Network Administrator. If you’re an experienced network engineer with many years under your belt, this is not your opportunity. But if you’re just getting into the networking field and are looking for a position where you can learn […]
The post Jr. Network Admin Willing to Work In Columbus, Ohio? Let’s Talk! appeared first on Packet Pushers Podcast and was written by Ethan Banks.
I've made my own handwritten font for those moments when you are "sketching" network diagrams and it is free for you to use.
The post Free Custom Handwriting Font for Network Designs appeared first on EtherealMind.
Cisco announced another 6000 job cuts in the Q4 2014 Results announcement yesterday in addition to the 5000 job cuts announced last quarter. Cisco has (or had) approx. 75000 employes so that’s a lot of jobs (more than 20%) in a short period of time and this leaves me pondering the impact to the products […]
The post Cisco Cuts Another 6000 Jobs Q4 2014 – Should I Be Concerned ? appeared first on EtherealMind.
As I announced earlier this summer, I'm working on writing a book targeted to people entering the field of computer networking. I've got a fair amount of content fleshed out already, but figured it might help to get some feedback on the tentative structure. The book is being written in a question-and-answer style, organized into chapters by subject.
Below is the preliminary table of contents. It's still very much a work in progress, but I'm curious what people think of this approach. Constructive criticism and suggestions for additional content are welcome!
Collection of useful, relevant or just fun places on the Internets for 13 August 2014 and a bit commentary about what I've found interesting about them:
The post Internets of Interest – 13 August 2014 appeared first on EtherealMind.
The current version of Maven in Homebrew at the time of writing is 3.2.2
This is great... unless one of the plugins in your project doesn't support it and then you have to downgrade :(
Fortunately it's not too painful
brew uninstall maven
brew tap homebrew/versions
brew install …
The current version of Maven in Homebrew at the time of writing is 3.2.2
This is great... unless one of the plugins in your project doesn't support it and then you have to downgrade :(
Fortunately it's not too painful
brew uninstall maven
brew tap homebrew/versions
brew install maven30
@dave-tucker
By Dennis Schwarz and Dave Loftus
It has been a few weeks since news broke of the Zeus Gameover variant known as newGOZ. As has been reported, the major change in this version is the removal of the P2P command and control (C2) component in favor of a new domain generation algorithm (DGA).
The DGA uses the current date and a randomly selected starting seed to create a domain name. If the domain doesn’t pan out, the seed is incremented and the process is repeated. We’re aware of two configurations of this DGA which differ in two ways: the number of maximum domains to try (1000 and 10,000) and a hardcoded value used (0×35190501 and 0x52e645).
Date based domain generation algorithms make for excellent sinkholing targets due to their predictability, and provides security researchers the ability to estimate the size of botnets that use them. With this in mind, we have gathered five days worth of newGOZ sinkhole data. Our domains are based on the first configuration, since this configuration seems to be used the most in the wild.
As with all sinkhole data, many variables can affect the accuracy of victims such as network topology (NAT and DHCP), timing, Continue reading