GNS3 on Fedora Linux

Here are mu notes about installation GNS3 version on Fedora Linux. It shows the basic steps required to successfully install and configure GNS3 for VirtualBox, Qemu, IOU, and Dynamips support. Configuration of individual VirtualBox, Qemu, IOU and IOS images is not discussed.

1. GNS3 GUI and Server Installation and Configuration

1.1 Install Dependencies

$ sudo yum install python3 python3-setuptools.noarch python3-PyQt4 python3-devel gcc

1.2 Download and Extract GNS3 GUI and Server

$ git clone https://github.com/GNS3/gns3-gui.git
$ git clone https://github.com/GNS3/gns3-server.git

$ cd gns3-gui/
$ sudo python3 setup.py install
$ cd ..

$ cd gns3-server/
$ sudo python3 setup.py install

1.3 Configure GNS3 Server Settings

Navigate to Edit-> Preferences-> GNS3 server-> Local server and change path to gns3server.

2. IOU Installation and Configuration

IOU stands for IOS on Unix. IOU images are IOS images that are compiled for x86 / Sparc CPU architecture.

2.1 Install Dependencies

$ sudo yum install gcc gcc-c++ git

2.2 Create Symbolic Link and Prevent IOU to Call Home

$ cd /usr/lib
$ sudo ln -s ./libcrypto.so.10 libcrypto.so.4
$ su -c "echo '127.0.0.127 xml.cisco.com' >> /etc/hosts"

2. Continue reading

Ansible for Network Automation – Part 2

Ansible for Network automation – Part 1

Network device configuration using templates with Jinja2 and YAML

It’s the Application Development, Stupid

I love reading blog posts on Plexxi blog (you SHOULD add them to your RSS reader) and the “It’s the Application, Stupid” series from Mat Matthews is no exception. What pleasantly surprised me was that a large enterprise came to the same conclusions I’m preaching for the last few years.

One More Thing: Keyless SSL and CloudFlare’s Growing Network

I wanted to write one more thing about Keyless SSL, our announcement from last week, before attention shifts to what we'll be announcing on Monday. Keyless allows us to provide CloudFlare's service without having private SSL keys stored locally on our edge servers. The news last week focused on how this could allow very large customers, like major financial institutions, to use CloudFlare without trusting us with their private keys.

But there's another use that will benefit the entire CloudFlare userbase, not just our largest enterprise customers, and it's this: Keyless SSL is a key part of our strategy to continue to expand CloudFlare's global network.

CloudFlare's Global Network Today

CloudFlare's network today consists of 28 edge data centers that span much of the globe. We have technical and security requirements for these facilities in order to ensure that the equipment they house remains secure. Generally, we're in Tier III or IV data center facilities with the highest level of security. In our San Jose facility, for instance, you have to pass through 5 biometric scans, in addition to multiple 24x7 manned guard check points, before you can get to the electronically locked cabinets housing our servers.

There Continue reading

Wi-Fi SNR to MCS Data Rate Mapping Reference

Click to Download Full Version (PDF)

Celebrating CloudFlare’s 4th Birthday

Since CloudFlare launched to the public four years ago today, we've always considered September 27th our birthday. We like to celebrate by doing something nice for our team and also for our customers. Two years ago, for example, we brought a cake into the office and then enabled free IPv6 support for all our customers.

Saturday is our birthday this year, so we decided to celebrate it a few days later when we'd all be back in the office on Monday, September 29th. That actually corresponds to the day we presented at the finals of the TechCrunch Disrupt startup contest where we launched. We ended up coming in second. Mike Arrington, the founder of TechCrunch, said we were basically "muffler repair for the Internet."

Looking back, that's actually not a bad description. At core, CloudFlare's mission is to help build a better Internet by fixing its biggest problems -- its metaphorical rusty mufflers. This year, we thought it would be great to repair a big, ugly muffler that should have been fixed a long time ago.

This Monday, we'll bring a cake into the office. (It'll have to be a lot bigger as our team has grown substantially.) Continue reading

HP switches: copy configuration between different device models

Knowing Your Audience…and Showing It

We all know that you’re supposed to “Know Your Audience.” Doing so improves engagement, and avoids faux pas like “Suggested Tweets.” But recently I realised that this doesn’t have to be subtle. Drop hints early on in your presentation that you’ve taken the time to understand the audience – it can really lift the mood.

Suggested Tweets – Just Say No

Companies that obsess about the wrong kind of metrics think that all they need is to get their message repeated many times. So they give employees & partners a list of “suggested tweets.” These are pre-written Tweets that people can send out from their own Twitter accounts, to “generate buzz.” I have seen many companies do this, and it is overwhelmingly lame. It devalues the message, and devalues those who send out these “suggested tweets.”

In the lead-up to the recent Cisco UCS event, many members of the Cisco Champions program sent out the same set of tweets. When I see the same tweet from several people in my stream, it’s obvious what’s going on. If you’re running a marketing Twitter account, then yeah, I expect marketing messages. But if you’re a real person, and I’ve Continue reading

TCP Is a Stream Protocol

I hope you know TCP provides a reliable stream service not reliable packet delivery, but you might not have realized all the implications – I found an old post by Robert Graham explaining how things really work and how you can use them to bypass quick-and-dirty IDS that rely on signatures instead of doing proper protocol decodes.

Classic IOS as a DNS Server

There is an occasional need for a DNS server in the absence of a dedicated host. This may occur in the following situations–

• Using PAT, Public DNS may return a non-RFC1918 address for internal server
• Lab/Demo Environment
• Other Name Resolution challenges in SOHO, SMB or Branch Office

When these corner-case challenges present, an IOS router may be beneficial by providing basic DNS functions. Assuming the router already has Internet connectivity, the configuration is straightforward–

//enable the dns server functionality
IOS-DNS(config)#ip dns server 

//if public requests should be resolved, configure one or more name
//servers as resolvers and confirm domain-lookups are enabled
IOS-DNS(config)#ip name-server 8.8.8.8 8.8.4.4
IOS-DNS(config)#ip domain-lookup

At this point the router should perform DNS resolution by relaying requests to the public name servers in the configuration. Hosts could use any IP address on the device in their DNS configuration. ACLs should be used to block DNS requests to interfaces that aren’t servicing clients.

To create DNS records for local resolution, the ip host command can be used.

IOS-DNS(config)#ip host ?
  WORD  Name of host
  view  Specify view
  vrf   Specify VRF

IOS-DNS(config)#ip host www.example.com ?
     Default telnet port number
  A.B.C.D     Host IP address
  additional  Append addresses
  mx          Configure a  Continue reading

Change HTTP reply content with AppShape++

Lab goal

Setup

I'll use my Loadbalancer Lab Setup.

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/c/slb/real 1
        ena
        ipver v4
        rip 10.136.85.1
/c/slb/real 2
        ena
        ipver v4
        rip 10.136.85.2
/c/slb/real 3
        ena
        ipver v4
        rip 10.136.85.3
/c/slb/group 10
        ipver v4
        add 1
        add 2
        add 3

Alteon configuration

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 /c/slb/virt 85_14
        ena
        vip 10.136.85.14
 /c/slb/virt 85_14/service 80 http
        group 10
 /c/slb/virt 85_14/service 80 http/pip
        mode address
        addr v4 10.136.85.200

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Plexxi Pulse—Preparing for Big Data

Plexxi Pulse—Preparing for Big Data

As enterprises launch Big Data platforms, it is necessary to tailor network infrastructure to support increased activity. Big Data networks must be constructed to handle distributed resources that are simultaneously working on a single task—a functionality that can be taxing on existing infrastructure. Our own Mike Bushong contributed an article to TechRadar Pro this week on this very subject where he outlines the necessary steps to prepare networks for Big Data deployments. He also identifies how software-defined networking can be used as a tool to alleviate bandwidth issues and support application requirements when scaling for Big Data. It’s definitely worth a read before you head out for the weekend.

In this week’s PlexxiTube of the week, Dan Backman explains how Plexxi’s Big Data fabric mitigates incast problems.

Check out what we’ve been up to on social media this September. Enjoy!

The post Plexxi Pulse—Preparing for Big Data appeared first on Plexxi.

Safe from Shellshock: How to protect your home computer from the Bash shell bug

On the surface, the critical “Shellshock” bug revealed this week sounds devastating. By exploiting a bug in the Bash shell command line tool found in Unix-based systems, attackers can run code on your system—essentially giving them access to your system. Bad guys are already developing exploits that use Shellshock to crack your passwords and install DDoS bots on computers. And since Bash shell is borderline ubiquitous, a vast swath of devices are vulnerable to Shellshock: Macs, Linux systems, routers, web servers, “Internet of Things” gizmos, you name it.To read this article in full or to leave a comment, please click here

Cisco device configuration using Netconf

Schprokits with Jeremy Schulman on Software Gone Wild

Jeremy Schulman was the driving force behind the Puppet agent that Juniper implemented on some Junos switches (one of the first fully supported Puppet-on-a-switch implementations). In the meantime, he quit Juniper and started his own company focused on a network automation product – more than enough reasons to chat with him on Software Gone Wild.

IPv6 in my streaming media? More likely than you think!

Not that I go out of my way to endorse one project/product over another, there is one that I have recently fallen in love with for streaming my media. Especially when it can use IPv6! So I needed a cross-platform solution for my streaming media needs. I was originally using XBMC, but only had it tied into the TV. I use several other computers and devices, in other locations outside of the house. So I read up on Plex. Got it installed with little to no effort, and could readily access my content where ever I was. I even tested this on my last trip to London, UK and was able to get a decent 1.2mbit/s stream from my house. Only issue was that it wasn’t using IPv6 in the app or accessing via plex.tv (server on that site only comes up with an IPv4 address).

So poking around I discovered 2 things: 1) I could access the Plex server directly at the IP/hostname of the server, and 2) there was a checkbox to enable IPv6!!

Simply browse to your Plex server, click on the settings icon (screwdriver + wrench), select Server, click on Networking and then “Show Continue reading

MidoNet for the Overlay, Cumulus Linux for the Underlay. Like Coffee and Cream.

VTEP is not the only way MidoNet customers can use a switch that runs Cumulus Linux as the underlay (physical network) for the virtual, overlay networks.

We’ve announced our partnership to work with Cumulus Networks earlier in 2014 to use Cumulus Linux as a Layer-2 VxLAN Gateway to bridge VLANs in the virtual network world to the VLANs in the physical world.

We’ve shipped that code as part of MidoNet version 1.6.

We now want to talk about how VTEP is not the only way MidoNet customers can use a switch that runs Cumulus Linux as the underlay (physical network) for the virtual, overlay networks.    Just don’t think of running a set of gateway switches as the only way to benefit from these devices, we see many opportunities and benefits.

Here are some examples why it makes sense :

Automation

Remember that Cumulus Linux IS Linux. It’s not a switch OS that just happens to be based on Linux.  It offers cloud automation capabilities that is so crucial to customers who are adopting to move towards building a Cloud. If you listen to Customers, Systems like Chef and Puppet are widely used in the deployment of systems like OpenStack, Continue reading

FCC advised on Remediation of Server-based DDoS Attacks

Yesterday, the Communications Security, Reliability and Interoperability Council (CSRIC), a federal advisory committee to the Federal Communications Commission (FCC), submitted its final report on Remediation of Server-based DDoS Attacks.

The CSRIC’s Working Group 5 was tasked with developing recommendations for communications providers to enable them to mitigate the impact of high volume DDoS attacks launched from large data center and hosting environments.

The final report includes a comprehensive look at the DDoS threat landscape, covering everything from the massive size of today’s attacks, to the potential for collateral damage. The report describes how DDoS attacks are becoming increasingly complex, how they are being used as a diversion “to distract security resources while other attacks are being attempted, e.g., fraudulent transactions.” The report also discusses how botnet architectures are becoming more sophisticated and difficult to trace.

Given this complex and challenging threat landscape, we were grateful for the opportunity to contribute. The CSRIC has adapted Arbor Networks best practices for DDoS incident response as the Six Phases for DDoS Attack Preparation & Response.

Roland Dobbins, senior analyst with Arbor’s Security Engineering & Response Team (ASERT), served as the Internet sub-group chairman of CSRIC IV WG5 – Server-Based Continue reading