When installing Fibre Optic cable care must be taken to ensure that cable is not bent beyond a certain radius. Most people believe this is to prevent breaking of the fibre core but there is a worse scenario.
The post Why Replacing The Fibre Optic Patch Lead Often Fixes Network Problems appeared first on EtherealMind.
The IT world is cyclical for sure. I’ve seen trends and topics repeating themselves over and over again in my relatively short time here. I find it interesting that we keep solving similar problems over and over again. I also find it fascinating that this particular issue leads to the reason why blogs are so important.
Questions abound in IT. It’s the nature of the industry. However, it’s not just new questions that we create when technology leaps past us. We keep asking the same questions over and over again. This is the field of study that created the FAQ, remember?
In recent memory, I find the same questions being asked over and over again:
You’ve probably asked those very same questions. Perhaps you found the answers you were looking for. Perhaps you’re still trying to figure it out. The problem is that those questions are still being asked. The industry should have evolved to the point where the simple questions have been answered with simple answers. Complex questions, or those questions that need more in-depth Continue reading
There’s nothing like taking a 12 hour road trip to help get caught up on podcasts. Even though I have a few more to go, I am feeling pretty accomplished with my progress.
One podcast episode jumped out at me as particularly interesting. This was the Risky Business 2014 [year] in review episode. This episode has the most interesting excerpts and commentary for breaches throughout this year. Have a listen by following the link below.
Risky Business #349 — 2014 in review | Risky Business
Disclaimer: This article includes the independent thoughts, opinions, commentary or technical detail of Paul Stewart. This may or may not reflect the position of past, present or future employers.
The post Risky Business #349 <– Wow, a LOT Happened in 2014 appeared first on PacketU.
Not ever thinking the job that’s in front of you is too little for your skill set (or pride).
Top 10 Network Management Blog Posts of 2014
As the year winds down, we were interested to discover our most viewed blog posts of 2014, our inaugural year of the Knetwork Knowledge blog. Not surprisingly, the majority of articles concern SDN. From the rise of production deployments among service providers to management concerns to job security worries, SDN continues to alter the network landscape, attempting to assert its place as the disruptive technology it promises to be.
These top 10 articles present a good snapshot of SDN’s evolution this year as well as the network issues in general. Here they are in order of popularity (See also our short summary of each one below):
Although I wasn't actively blogging this year, I've still been tracking views on the site and keeping an eye on number of visitors. I am looking forward to blogging again in 2015 so I wanted to collect the 2014 viewership statistics so I had something to compare to at the end of 2015.
Despite the lack of new content, I'm pretty happy that people are reading the existing articles and continue to post comments and email me questions. Please keep them coming!
HP Networking has three solutions for overlay or virtual networking in the Data Centre. Each solution meets different customer needs Show Notes HP Networking has three products for network virtualization and each product addresses different customers needs. NSX Federation – physical networking integrating with NSX Distributed Cloud Networking (DCN) Virtual Cloud Networking (VCN) NSX Federations […]
The post PQ Show 39 – HP Networking – 3 Virtual Network Strategies Compared appeared first on Packet Pushers Podcast and was written by Greg Ferro.
Picking up where we left off on the first series, I want to discuss the other trunking option that we have in regards to PVLAN trunks. We might need a quick review on our PVLAN structure before we begin, however:
vlan 100 private-vlan primary private-vlan association 200-201 vlan 200 private-vlan community vlan 201 private-vlan isolated
This second trunk type is actually called the secondary, or isolated trunk. Much like the promiscuous trunk, this one has a pretty specific purpose, and that is to flip the VLAN tag when a frame is traversing a trunk. This time however, rather than removing the secondary VLAN tag, and replacing it with the primary tag, we are going to be doing the opposite! Remember how we were doing it with the promiscuous trunk? What happened here is the node with MAC A ingresses and is placed in VLAN 200. However, when it needs to reach the L3 GW (the router), we have to remove the secondary VLAN tag and replace it with the primary VLAN ID of 100 (so that it will hit the proper sub-interface on the router).
The routers return traffic will naturally be in VLAN 100 based on the sub-interface configuration. But Continue reading
Many old-style marketing people believe that capturing your contact information is the first step in making a sale. But any capture of your personal information is also leaking critical security information about your organisation, technology and personnel that are perfect for reconnaisance.
The post Vendor Marketing as a Security Risk – Badge Scans and Sign-up Attack Vectors appeared first on EtherealMind.
Last time, we talked a little about making certain your presentation has a point — or a porpoise, as the case might be. This time I want to talk about a few other common mistakes I see network engineers make when building presentations, and actually presenting them.
First, you put too much text on your slides. I know you’re afraid you’re not going to remember everything you want to say, but that’s no excuse to have a 500 word essay on every slide. The bullet points on a slide are supposed to be just that — bullet points. They’re supposed to remind you of what you mean to say at this point in the presentation, not to be the actual words you’re planning on saying.
Okay, I understand we’re running head in to another problem here — what about folks who print my presentation out and take it home to read it later? That’s what hidden slides are for. Put all the text you really want to put into a slide on a hidden slide just after the slide itself. Then pull out just enough words for you to remember what’s on the hidden slide when you’re doing the presentation. Continue reading
Let’s return to our simple four AS network to look at a number of issues with BGPSEC — the bits you won’t often hear discussed in just about any forum. Assume, for a moment, that AS65000 advertises some route, say 192.0.2.0/24, to AS65001, and not to AS65002. For whatever reason, a few days pater, the […]
The post BGPSEC: Replays, Timers, and Performance appeared first on Packet Pushers Podcast and was written by Russ White.
A long time ago, Packet Pushers ran an OSPF Design Part 1 show. That show went after the default design guides that network engineers have been reading for years, making the big point that you can scale a single OSPF area quite large indeed. But…that’s not the entire story about OSPF areas. Areas still have their use cases, […]
The post Show 218 – OSPF Design Part 2 appeared first on Packet Pushers Podcast and was written by Ethan Banks.
Recently I have read a question on GNS3 forum asking whether Qemu supports more than 8 network adapters. According to Google search, maximum number of adapters for Qemu virtual machines can be configured with a parameter #define MAX_NICS 8 in a file ./include/net/net.h under Qemu source tree. After you set desirable value you must compile and install Qemu from source.
However I have noticed that changing the integer value in the line #define MAX_NICS has no effect on the maximum number of NIC allowed for Qemu VMs. I notice that I can start Core Linux Qemu machine with 18 network adapters even Qemu 2.2.0 was compiled with parameter #define MAX_NICS set to 1.
Now we know that Qemu itself does not limit the maximum network adapters to 8. We will go ahead and investigate GNS3. Navigate to Edit -> Preferences -> QEMU VMs and click on existing Qemu VM. Click on Edit button for this VM and navigate to Network tab. Increase the number of Adapters to 9.
The GNS3 1.2.1 allows to add maximum 8 NICs for a particular Qemu virtual machine. To avoid this limitation we have edit GNS3 source files and recompile GNS3 GUI and server. Here are the the steps for Linux.
1. Download and extract GNS3 1.2.1 Linux Continue reading
In an effort to educate myself on the inner workings of WebEx, I recently looked at a session with Wireshark. Knowing that WebEx audio has the ability to use UDP or TCP, I wanted to isolate the protocol being employed in my configuration. I watched for a new stream of traffic as I enabled the audio portion of a meeting. I found that the audio was using UDP port 9000.
I next applied a filter to see only this traffic. What immediately jumped out at me was what appeared to be malformed and fragmented packets. I also noticed a lot of strange IP addresses like 1.0.0.0, 1.0.0.1, 0.0.0.30, 0.0.0.31 and so on.
Knowing that the audio was working perfectly, I could have easily concluded that my eyes were deceiving me. When I looked closer, I quickly realized that Wireshark was recognizing and decoding this as if the packets were Lawful Intercept.
This is a common scenario and the solution is straightforward. In Wireshark, right-click any of the packets and choose Decode As…
At this point, a new window will appear. Make sure the Transport tab is selected then choose Do Continue reading
