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DevCentral > Weblogs > Lori MacVittie - Two Different Socks

load-balancing

There are 15 entries for the tag load-balancing

Optimize Prime: The Self-Optimizing Application Delivery Network

Infrastructure 2.0 enabled application delivery platforms have more than a few things in common with the Transformers. Like Autobots, there’s more to it than meets the eye. If you’re familiar with the mythology of the Transformers – and perhaps even if you aren’t – you know that they key attribute of Transformers is their ability to take on “alternate modes” such as cars, trucks, and winged vehicles simply by scanning the object and then adapting their own form to match. One of the key premises of Infrastructure 2.0 is also the ability of network and...


posted @ Tuesday, January 12, 2010 3:02 AM | Feedback (2)

Infrastructure Matters: Challenges of Cloud-based Testing

An interesting thing happened on the way to testing that application from the cloud. We broke the innertubes! Pros and Cons of Application Testing in the Cloud A firm wanted to test their application and need 100 browser instances. In the old days it would have required 100 machines -- that would be a massive undertaking. Even with hardware virtualization, you would need 5 to 10 machines, and there would be some complex configuration issues. However, by putting it all in the cloud, they were able to sync up 100 virtual instances of the browsers and take them down over...


posted @ Wednesday, June 10, 2009 3:24 AM | Feedback (4)

Virtualization Gone Wild: Infrastructure as virtual appliances

It has been suggested more than once, by folks normally considered rational, that in a cloud computing implementation everything - and I mean everything - should be virtualized. Even the infrastructure. The hype surrounding virtualization has spread not just to applications and their virtual image deployment as a means to achieve dynamic horizontal scale but also to infrastructure, to routers and switches and security devices. Indeed, there are a good number of infrastructure vendors currently offering and others feverishly working on virtual appliance versions of hardware devices for deployment in cloud and virtual computing environments. Part...


posted @ Monday, January 12, 2009 4:29 AM | Feedback (7)

What's good for the network is not always good for applications

Just because you can, doesn't mean you should. I'm going to start this one by quoting Hoff who was quoting Andreas Antonopoulos of Nemertes Research Group who was paraphrasing a concept put forth by Doug Gourlay. From Rational Survivability "How about using netflow information to re-balance servers in a data center" Routing: Controlling the flow of network traffic to an optimal path between two nodes Virtual-Routing or Anti-Routing: VMotioning nodes (servers) to optimize the flow of traffic on the network. Using netflow information, identify those...


posted @ Wednesday, December 17, 2008 4:03 AM | Feedback (0)

The Secret Knowledge of Developers that Network Administrators Want

When an application is deployed into a high-availability production environment there are a number of interesting infrastructure related things need to happen. The application delivery controller (ADC) needs to be configured, DNS entries updated, storage allocated, and all the other associated network infrastructure must be prepared to handle the delivery of the new application.  We have a BIG-IP. Do I have to talk to the network guys?? ...


posted @ Tuesday, December 16, 2008 5:55 AM | Feedback (3)

2.5 bad ways to implement a server load balancing architecture

I'm in a bit of mood after reading a Javaworld article on server load balancing that presents some fairly poor ideas on architectural implementations. It's not the concepts that are necessarily wrong; they will work. It's the architectures offered as a method of load balancing made me do a double-take and say "What?"  I started reading this article because it was part 2 of a series on load balancing and this installment focused on application layer load balancing. You know, layer 7 load balancing. Something we at F5 just might know a thing or two about. But you...


posted @ Friday, October 24, 2008 7:55 AM | Feedback (2)

Can the future of application delivery networks be found in neural network theory?

I spent a big chunk of time a few nights ago discussing neural networks with my oldest son over IM. It's been a long time since I've had reason to dig into anything really related to AI (artificial intelligence) and at first I was thinking how cool it would be to be back in college just exploring topics like that. Then, because I was trying to balance a conversation with my oldest while juggling my (fussy) youngest on my lap, I thought no, no it wouldn't. Artificial neural networks (ANN) are good for teaching a system how to...


posted @ Thursday, October 09, 2008 3:57 AM | Feedback (1)

Bursting the Cloud

The cloud computing craze is leading to some interesting new terms. Cloudware and cloudbursting are two terms I particularly like for their ability to describe specific computing models based on cloud computing. Today we're going to look at cloudbursting, which is basically a new twist on an old concept. Cloudbursting appears to be to marry the traditional safe enterprise computing model with cloud computing; in essence, bursting into the cloud when necessary or using the cloud when additional compute resources are required temporarily. Jeff at Amazon Web Services Blog talks about the inception of this term as applied...


posted @ Wednesday, September 03, 2008 5:10 AM | Feedback (1)

Dear Data Center Guy

You walked past me again today without stopping. I remember when you used to stop and admire my glowing red ball every day. But that was back when I was brand new and you thought I was the center of your data center. I heard you talking to some friends about looking for a web acceleration solution yesterday. You were going to a meeting about it later that afternoon and you were so excited it was almost like old times, until you pointed me out on the way by and said, "Oh yeah, there's our load balancer." ...


posted @ Friday, August 29, 2008 4:05 AM | Feedback (2)

I do not think that word means what you think it means

Greg Ferro over at My Etherealmind has a, for lack of a better word, interesting entry in his Network Dictionary on the term "Application Delivery Controller." He says: Application Delivery Controller (ADC) - Historically known as a “load balancer”, until someone put a shiny chrome exhaust and new buttons on it and so it needed a new marketing name. However, the Web Application Firewall and Application Acceleration / Optimisation that are in most ADC are not really load balancing so maybe its alright. Feel free to call it a load balancer when the sales rep is on the ground, guaranteed to...


posted @ Friday, August 22, 2008 4:49 AM | Feedback (7)

Reliability does not come from SOA Governance

An interesting InformationWeek article asks whether SOA intermediaries such as "enterprise service bus, design-time governance, runtime management, and XML security gateways" are required for an effective SOA. It further posits that SOA governance is a must for any successful SOA initiative. As usual, the report (offered free courtesy of IBM), focuses on SOA infrastructure that while certainly fitting into the categories of SOA intermediary and governance does very little to assure stability and reliability of those rich Internet applications and composite mashups being built atop the corporate SOA. Effective SOA Requires Intermediaries via InformationWeek ...


posted @ Monday, August 18, 2008 5:00 AM | Feedback (1)

Layer 7 Switching + Load Balancing = Layer 7 Load Balancing

Modern load balancers (application delivery controllers) blend traditional load-balancing capabilities with advanced, application aware layer 7 switching to support the design of a highly scalable, optimized application delivery network. Here's the difference between the two technologies, and the benefits of combining the two into a single application delivery controller. LOAD BALANCING Load balancing is the process of balancing load (application requests) across a number of servers. The load balancer presents to the outside world a "virtual server" that accepts requests on behalf of a pool (also called a cluster or farm) of servers and distributes those requests...


posted @ Tuesday, August 12, 2008 4:44 AM | Feedback (3)

Persistent and Persistence, What's the Difference?

The English language is one of the most expressive, and confusing, in existence. Words can have different meaning based not only on context, but on placement within a given sentence. Add in the twists that come from technical jargon and suddenly you've got words meaning completely different things. This is evident in the use of persistent and persistence. While the conceptual basis of persistence and persistent are essentially the same, in reality they refer to two different technical concepts. Both persistent and persistence relate to the handling of connections. The former is often used as a general...


posted @ Friday, July 11, 2008 5:12 AM | Feedback (0)

The Disadvantages of DSR (Direct Server Return)

I read a very nice blog post yesterday discussing some of the traditional pros and cons of load-balancing configurations. The author comes to the conclusion that if you can use direct server return, you should. I agree with the author's list of pros and cons; DSR is the least intrusive method of deploying a load-balancer in terms of network configuration. But there are quite a few disadvantages missing from the author's list. Author's List of Disadvantages of DSR The disadvantages of Direct Routing are: Backend server...


posted @ Thursday, July 03, 2008 4:29 AM | Feedback (10)

Web 2.0: Integration, APIs, and Scalability

Web 2.0 is built on primarily two technologies: AJAX and RSS. AJAX is used to develop interactive, real-time applications while RSS is primarily used as for integration and syndication. Import a feed, share a feed, drag-n-drop a gadget, widget, or component. It's all RSS (XML) today. It's further becoming a requirement of Web 2.0 sites that they provide some sort of API through which developers can write add-on applications. Twitter, Tumblr, Facebook. They all offer APIs that are quite heavily used at this time and startups are following suit. Other sites offer richer media, like video or slideware,...


posted @ Tuesday, July 01, 2008 4:53 AM | Feedback (1)