Using NVI to Allow Internal Hosts to Connect to Public Addresses of Hosted Servers

IP NAT is a very common configuration. One of the challenges that sometimes surfaces is the need for internal hosts to connect to the public address of a locally hosted server. Anyone who has tried to configure something like the following has likely faced this issue.

In this example, the top of the diagram represents the outside (Internet, ISP, or External Server), the left represents the DMZ area, and the bottom represents the inside. The goal is to enable dynamic port address translation for internal hosts and static port address translation for the host or hosts found in the DMZ area.

This configuration is fairly straightforward and typically covered in the CCNA curriculum. This includes identifying each interface as inside or outside and configuring the appropriate nat statements.

R1 Configuration

interface FastEthernet1/0
 description To INSIDE
 ip address 192.168.1.1 255.255.255.0
 ip nat inside
!
interface FastEthernet1/1
 description To ACME WWW
 ip address 192.168.2.1 255.255.255.0
 ip nat inside
!
interface FastEthernet1/2
 description To OUTSIDE
 ip address 192.0.2.100 255.255.255.0
 ip nat outside
!
ip nat inside source list 1 interface FastEthernet1/2 overload
ip nat inside source static tcp 192.168. Continue reading

No more duplicate frames with Gigamon Visibility Fabric

Gigamon presented their Visibility Fabric Architecture at Network Field Day 8.  You can watch the presentation at Tech Field Day.

CC BY-NC-ND 2.0 licensed photo by smif Needs deduplication

One of the interesting facets of Gigamon's solution was it's ability to do real-time de-duplication of captured traffic as it traverses the Visibility Fabric (a hierarchy of monitoring data sources and advanced aggregation switches). I've spent some time around proactively-deployed network taps, but never seen this capability before, and I think it's pretty nifty.

The Problem
Let's say you've got taps and mirror ports deployed throughout your network. They're on the uplinks from data center access switches, virtually attached to vSwitches for collecting intra-host VM traffic, at the WAN and Internet edge, on the User distribution tier, etc...  All of these capture points feed various analysis tools via Gigamon's Visibility Fabric. It's likely that a given flow will be captured and fed into the monitoring infrastructure at more several points. Simplistic capture-port-to-tool-port forwarding rules will result in a given packet being delivered to each interested tool more than once, possibly several times.

This can be problematic because it confuses the analysis tool (ZOMG, look at all Continue reading

Getting the Sourcefire Firepower VM working Inline

The Sourcefire NGIPS/NGFW solution is a way to quickly get some interesting information about traffic on a network. One of the things I like about the solution is that actionable information is almost immediately available after deployment.

There are five deployment modes for a Sourcefire Firepower appliance:

• Routed
• Switched
• Hybrid
• Inline
• Passive

Passive and inline modes are the two deployment options for the Virtual versions of the Firepower appliances. Inline mode provides significant advantages over simple passive monitoring. Inline mode allows the appliance to block offending traffic or communications that violates the configured policy. Following the installation guide is straightforward and should allow a security engineer to quickly get this solution up and running.

The first time I ran through this process, I couldn’t get traffic to flow through the inline appliance. After struggling a while, I reconfigured the device into passive mode and spanned some traffic over to it. At first I didn’t see any statistics. After realizing that I also needed to configure VMWare to accept promiscuous mode, I quickly started getting interesting information in the Firesight dashboard.

At this point, a thought occurred to me. What if the Firepower appliance had no layer 2 hooks and forwarded traffic that blindly Continue reading

Integrating Spirent into an Automated Workflow Test Methodology

HTTP to HTTPs redirect with a twist

Lab goal

Setup

Alteon configuration

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 /c/slb/virt 86_13
        ena
        ipver v4
        vip 10.136.85.13
 /c/slb/virt 86_13/service 80 http
        group 10
        rport 80
 /c/slb/virt 86_13/service 80 http/pip
        mode address
        addr v4 10.136.85.200 
 /c/slb/virt 86_13/service 443 https
        group 10
        rport 443
 /c/slb/virt 86_13/service 443 https/pip
        mode address
        addr v4 10.136.85.200 

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when HTTP_REQUEST {
    # exctract the fields from the HTTP headers
    set url [ Continue reading

How to avoid online scams when selling your old iPhone or iPad

A lot of people right now are selling their old iPhones and iPad minis to trade up to the supersized iPhone 6 models. Unfortunately, I suspect some of them are being scammed out of their devices — I nearly was.I’m itching for a 64GB iPhone 6 Plus (Space Gray, please). To partly finance Apple’s turkey-platter-sized phablet, I decided to sell my first-generation iPad mini on Amazon. That’s where my scamming saga begins.Within one day of listing the tablet, I received an Amazon email from "Kimberly." She expressed interested in my mini and asked me to send pictures to her personal Yahoo email address.It seemed like a reasonable request, so I emailed a few pictures to her. She soon replied via her Yahoo email and asked for my Amazon seller name. I was a tad suspicious because she was communicating with me directly instead of going through Amazon’s messaging system, but I replied.To read this article in full or to leave a comment, please click here

Network Break 16

This week, EVO:RAIL & Converged thingies, Cisco's multiple SDN strategies, Don't be a precious snowflake and Congress open source project.

Author information

Greg Ferro

Greg Ferro is a Network Engineer/Architect, mostly focussed on Data Centre, Security Infrastructure, and recently Virtualization. He has over 20 years in IT, in wide range of employers working as a freelance consultant including Finance, Service Providers and Online Companies. He is CCIE#6920 and has a few ideas about the world, but not enough to really count.

He is a host on the Packet Pushers Podcast, blogger at EtherealMind.com and on Twitter @etherealmind and Google Plus.

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The post Network Break 16 appeared first on Packet Pushers Podcast and was written by Greg Ferro.

Sprint, Windstream: Latest ISPs to hijack foreign networks

Last year my colleague Jim Cowie broke a story about routing hijacks that resulted in Internet traffic being redirected through Iceland and Belarus. Unfortunately, little has changed since then and the phenomenon of BGP route hijacking continues unabated and on an almost daily basis.

In the past three days, the situation has gone from bad to downright strange as we have observed a flurry of this activity. Now, for the first time, we’re seeing major US carriers, Sprint and Windstream, involved in hijacking, along with the return of an operation out of Poland targeting Brazilian networks. We see router misconfigurations regularly in BGP data – could these incidents also be explained by simple command-line typos?

Route hijacking continues

In May my colleague, Earl Zmijewski gave a presentation about routing hijacks at the LINX 85 meeting, describing a comprehensive system that can be used to identify suspicious hijacks on a global basis and without any prior knowledge about the networks involved. While we now detect suspicious routing events on an almost daily basis, in the last couple of days we have witnessed a flurry of hijacks that really make you scratch your head.

To mention a few recent events, last Continue reading

FEMA and Your Business Continuity Plan

I passed the ROUTE exam a few days/weeks/months/something ago and decided to pursue certifications of another sort for a while. The wife and I are trying our best to help the community through our ham radio training, so I decided to go down that path a bit further. One thing I was interested in doing is to do EmComm during declared emergencies. That meant I had to take two FEMA courses online to be allowed in the EOC. I thought they would be terribly boring, but I found them to be quite familiar.

The first course was on the Incident Command System (ICS). The main idea is that, in the event of an emergency of any kind or size, an Incident Commander (IC) is assigned to be responsible for the recovery effort.  This mean analysis of the incident, generating an action plan (a very key component), and execution of said plan. If the IC can complete the action plan by himself, then off he goes. If he or she needs some additional resources like people or equipment, then he or she is empowered to draft that help from any entity that’s involved.

Another one of the big points of ICS is Continue reading

Tech Talks: The Essence of MPLS

Seamus Gilchrist sent me a fantastic list of MPLS- and MPLS-TE-related questions. Instead of starting an email exchange we agreed on something that should benefit a wider community: a lengthy whiteboard session discussing the basics of MPLS, MPLS-TE, load balancing and QoS in MPLS networks…

The first part of our conversation is already online: The Essence of MPLS.

HP proposes hybrid OpenFlow discussion at Open Daylight design forum

We would like to share our experiences with Customer SDN deployments that require OpenFlow hybrid mode. Why it matters, implementation considerations, and how to achieve better support for it in ODL

OpenFlow-compliant switches come in two types: OpenFlow-only, and OpenFlow-hybrid. OpenFlow-only switches support only OpenFlow operation, in those switches all packets are processed by the OpenFlow pipeline, and cannot be processed otherwise. OpenFlow-hybrid switches support both OpenFlow operation and normal Ethernet switching operation, i.e. traditional L2 Ethernet switching, VLAN isolation, L3 routing (IPv4 routing, IPv6 routing...), ACL and QoS processing

The rationale for supporting hybrid mode is twofold:

1. Controlled switches have decades of embedded traditional networking logic. The controller does not add value to a solution if it replicates traditional forwarding logic. One alternative controller responsibility is that provides forwarding decisions when it wants to override the traditional data-plane forwarding decision.
2. Controllers can be gradually incorporated into a traditional network. Continue reading

IDF 2014: Architecting for SDI, a Microserver Perspective

This is a liveblog for session DATS013, on microservers. I was running late to this session (my calendar must have been off—thought I had 15 minutes more), so I wasn’t able to capture the titles or names of the speakers.

The first speaker starts out with a review of exactly what a microserver is; Intel sees microservers as a natural evolution from rack-mounted servers to blades to microservers. Key microserver technologies include: Intel Atom C2000 family of processors; Intel Xeon E5 v2 processor family; and Intel Ethernet Switch FM6000 series. Microservers share some common characteristics, such as high integrated platforms (like integrated network) and being designed for high efficiency. Efficiency might be more important than absolute performance.

Disaggregation of resources is a common platform option for microservers. (Once again this comes back to Intel’s rack-scale architecture work.) This leads the speaker to talk about a Technology Delivery Vehicle (TDV) being displayed here at the show; this is essentially a proof-of-concept product that Intel built that incorporates various microserver technologies and design patterns.

Upcoming microserver technologies that Intel has announced or is working on incude:

• The Intel Xeon D, a Xeon-based SoC with integrated 10Gbs Ethernet and running in a Continue reading

Poster: State of SDN in 2014

The post Poster: State of SDN in 2014 appeared first on EtherealMind.

Tools for Learning Python for Networkers

I’ve been slowly adding to my list of favorite tools and books for learning Python, and I came across a new one this week. So it seemed like a good time to hit the highlights in a blog post, given that so many networkers have some motivation to learn a programming language. Feel free to comment and add your favorite tools to the list!

Context: Networkers Learning a Language (Python)

First, let me throw in a quick paragraph for context. In this world of SDN, NFV, and network automation and programmability, networking people may or may not choose to go learn a programming language. (What are your plans?)

If you do choose to learn a language (as the poll results show so far at least), Python seems to be the best choice if programming is either new to you, or you just haven’t had to (gotten to?) program as a regular part of a job. Python is the simplest to learn of the languages that matter most to SDN, and is becoming the language-of-choice for more and more universities as the first language learned by undergrads.

On to the Continue reading

Troubleshooting an ESXi host using esxtop

Open-Source Hybrid Cloud Reference Architecture on Software Gone Wild

A while ago Rick Parker told me about his amazing project: he started a meetup group that will build a reference private/hybrid cloud heavily relying on virtualized network services, and publish all documentation related to their effort, from high-level architecture to device and software configurations, and wiring plans.

In Episode 8 of Software Gone Wild Rick told us more about his project, and we simply couldn’t avoid a long list of topics including:

Alteon AppShape++ Redirects

Lab goals

Setup

I'll use my Loadbalancer Lab Setup.

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10.136.6.11     3.dans-net.com
10.136.6.11     r.dans-net.com

Alteon configuration

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/c/slb/group g1
        ipver v4
        add 1
/c/slb/group g2
        ipver v4
        add 2
/c/slb/group g3
        ipver v4
        add 3

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 /c/slb/ Continue reading

IPv6 Neighbor Discovery (ND) and Multicast Listener Discovery (MLD) Challenges

A few days ago Garrett Wollman published his exasperating experience running IPv6 on large L2 subnets with Juniper Ex4200 switches, concluding that “… much in IPv6 design and implementation has been botched by protocol designers and vendors …” (some of us would forcefully agree) making IPv6 “…simply unsafe to run on a production network…”

The resulting debate on Hacker News is quite interesting (and Andrew Yourtchenko is trying hard to keep it close to facts) and definitely worth reading… but is ND/MLD really as broken as some people claim it is?

Network Neutrality Is a Political, Not Technical, Problem

Network Neutrality is a Political, Not Technical, Problem

We've mentioned Network Neutrality several times before on the Knetwork Knowledge Blog, but I wanted to take another look at it since it's back in the news with Wednesday's planned protests by "BattleForTheNet.com" - an artificial "Internet Slowdown" that will create symbolic "loading" symbols and artificially slow down page loading. Participating websites include Kickstarter, Reddit, Foursquare, Vimeo, Namecheap, and others. 

Packet Design has differing opinions on the issue of network neutrality. This is a bit surprising when you consider network neutrality as a technical issue, because you would expect that the engineering and mathematics would speak for themselves. It should be relatively easy to prove, from a technological standpoint, whether a neutral or particular non-neutral Internet scheme would be "better." 

But the minute you ask "better for whom?" you start to realize that network neutrality is not a technical problem. It is a political problem that happens to involve technology. 

As our CTO Cengiz Alaettinoglu said in "Hot Potatoes and Network Neutrality," BGP and IGP routing delivers packets to the next autonomous system (AS) in the route Continue reading

IDF 2014: Virtualizing the Network to Enable SDI

This is a liveblog of IDF 2014 session DATS002, titled “Virtualizing the Network to Enable a Software-Defined Infrastructure (SDI)”. The speakers are Brian Johnson (Solutions Architect, Intel) and Jim Pinkerton (Windows Server Architect, Microsoft). I attended a similar session last year; I’m hoping for some new information this year.

Pinkerton starts the session with a discussion of why Microsoft is able to speak to network virtualization via their experience with large-scale web properties (Bing, XBox Live, Outlook.com, Office, etc.). To that point, Microsoft has over 100K servers across their cloud properties, with >200K diverse services, first-party applications, and third-party applications. This amounts to $15 billion in data center investments. Naturally, all of this runs on Windows Server and Windows Azure.

So why does networking need to be transformed for the cloud? According to Pinkerton, the goal is to drive agility and flexibility for your business. This is accomplished by pooling and automating network resources, ensuring tenant isolation, maximizing scale/performance, enabling seamless capacity expansion and workload mobility, and minimizing operational complexity.

Johnson takes over here to talk about how Intel is working to address the challenges and needs that Pinkerton just outlined. This breaks down into three core Continue reading