Development / General IT Goodness

Mashup: SDBP Boston, Caching and iRules - oh my!

Colin Walker — Thu, 06 Nov 2008 17:28:20 GMT

Whew! It's been a whirlwind of a couple weeks. Between the annual F5 sales conference, where Joe and I presented to a bunch of awesome F5 techies, followed immediately by a very cool trip to present with the famed Lori at the SD Best Practices event in Boston, I've barely had time to do laundry, sleep in my own bed and feed my puppy. It's good to be back, but what cool stuff I got to see/hear/talk about!

The Software Development Best Practices (SDBP) conference was hawesome. It's great to be around so many people that get "it" and share the same geeked out passion for development, computing and cool technology that I do. While there I not only got to have several awesome conversations while hanging out in the F5 booth on site, but also got to give a fun Technical Session with Lori (which she mentioned before we left) which I think went over pretty well. It was F5's first time at this conference but hopefully not our last, as I think the audience is a great one to get in front of when talking about the amazing things that our gear can do to help extend the application. Whether it's via standard LTM features, iControl or iRules, it's almost always a killer story.

One of the many stories we told when talking about things we can do for the application was the Joyent / Bumpersticker application story. For those of you that haven't heard it yet, I highly recommend checking it out. We've got some pretty detailed info in the interview that Joe and I did with Jason, their CTO, which you can check out here. The short version is that Joyent scaled Bumpersticker app from Linkedin to over a billion pageviews a month, running on Ruby on Rails, and they couldn't have done it without F5 and iRules. How cool is that?!?

They did this via a combination of intelligent caching and a smattering of iRules that garnered an 80% reduction in application load (80%!!11), allowing them to get way more bang for their processing buck. This, along with some other cool conversations I had regarding caching and some of the things we can do with it, led me to put together a tech tip that begins to delve into the world of caching and iRules on the LTM. More detail will follow I'm sure, but this starts the journey at least.

That's all for now, more later as always.

Technorati Tags: SDBP,Caching,iRules,Joyent,LinkedIn,Facebook,Ruby on Rails,Colin Walker

Listening to: Alter Bridge - One Day Remains - One Day Remains

#Colin

Google, Twitter and Other Web Giants Change Political Debate Forever

Colin Walker — Tue, 07 Oct 2008 18:43:17 GMT

Google, Twitter, Facebook, Myspace, iTunes - They've all been changing the way that the average person goes about their day for a long time now. The thing that sets these monolithic figures in technological history apart from others is that they are not only changing the game for those of us that have long been denizens of the web. Indeed they are making the web and the delicious, bountiful fruits therein accessible to the masses. This is what is allowing them to change the face of the world as we know it.

A prime and quite pointed example of exactly how these giants of the technological industry are helping to shape the course of history is the data that Google released yesterday. In their blog Google gives us information the likes of which wouldn't have been more than a plot point in some science fiction novel not 15 years ago. Google showed us by the minute stats of the most popular search terms that people were using during the VP debates. Being able to present this kind of information in such a granular format over such a broad spectrum of the populous is absolutely astounding.

This shows not only the immense power of Google searches, and their obviously immense ability to track inconceivable amounts of statistical information, but something most assuredly more surprising and impressive. This is an amazing display of just how prevalent and mainstream Google searches have become. The fact that the average American viewing the debates knows how to use Google to search for things is fantastic. What's shocking is that an apparently large portion of that group knows how to use the protocol appropriately, performing what could be characterized as more skilled searches, such as "define:maverick".

Think about how this has changed things. 15 years ago, if you weren't informed by the time of the debates, it was too late. If you hadn't done your duty as a citizen and read, listened and researched to get aware of what was going on and the issues at hand, there was no way to catch up this late in the game, and certainly not real-time while watching the debates occur.

If that's not enough for you, there's another really cool example of technology, in this case Twitter and Current.tv, giving us yet another way to watch the debates while sharing information and opinions. RWW has a great article about the video streaming collaboration that includes a twitter overlay of comments happening real-time during the debate. The example video on the above linked page is pretty cool, and worth a quick view.

What does all of this mean? It means that advanced technology and the world wide web isn't just for us geeks anymore. It means that there are some pretty major forces at play here and that technology is very mainstream, very powerful, and is definitely having an affect on the way people go about their business, especially when it comes to finding/using/gathering/distributing information. I guess that shouldn't come as a surprise. It sounds awfully "Yeah, duh!" when I say it like that, but these examples seemed awfully compelling to me, and I thought I'd share.

Technorati Tags: Google Chrome,Twitter,Facebook,Myspace,iTunes,Current.tv Presidential Election,RWW,Colin Walker

#Colin

Listening to: Apocalyptica - Apocalyptica - Betrayal/Forgiveness

Motorola builds an army of Android devs with plans to take over the mobile world

Colin Walker — Mon, 29 Sep 2008 19:10:34 GMT

Android, Google's hot new mobile device platform, is the buzz around the mobile world, especially amongst the giants like Motorola and Nokia. They've been looking for a way to crack the iPhone market for a while now, and Android seems to be the pony they're betting on.

TechCrunch has the whole article detailing how Motorola is expanding their current, 50 person Android development team up to a whopping 350 members. This makes sense given the reception that Android as a whole and the new G1 phone as an example of its use have gotten. There may be some things lacking and a little polish to be added, but there's no debating that it's got some serious potential to compete against the current 800-lb gorilla of the mobile PC market - the iPhone.

As much exuberance as I've emitted regarding the G1, I have to say this is even more exciting for me. I've been a long-time Motorola fan. They just seem to "get it" when it comes to mobile phones. They work well, they have the features I want, implemented well, they're reliable, and even good looking most times. The G1 was exciting to me from a raw technologic standpoint. This is that AND a "day-to-day use" excitement. Woohoo!

I guess this means I'll have to look out for info on the new Motorola offerings and see if they are coming out with anything sometime in the near future. If so, I might just have to put off my G1 plans on wait for that. That all depends on ship-dates though, I suppose. Regardless of my personal situation, it sure is cool to see the Android platform taking off so quickly and catching so much well deserved interest from the major players in the market.

A flexible, powerful, well-built mobile platform that's also open and offers a cool, powerful new platform for development can only be a good thing, if you ask me.

Technorati Tags: Android,Motorolla,Nokia,iPhone,Mobile Devices,Colin Walker

#Colin

Google's new media-equipped phone doesn't support headphones. Wait...what?

Colin Walker — Tue, 23 Sep 2008 20:47:22 GMT

Well I knew it couldn't be all sunshine and roses. I started poking around looking at more info on the new phone from T-Mobile and Google, the G1, that I was just talking excitedly about an hour or so ago. So far first impressions have been resoundingly positive which is awesome, to say the least. There's always a catch though, isn't there?

Cynical geeks across the globe were heard howling in distaste the second they discovered that the new G1 has opted to not include a standard headphone jack in favor of the proprietary connector they favor. What's that? A media phone with MP3 storage/downloading that you have to buy new headphones or at least an adapter for? Ick.

Check it out over on engadget.

Honestly that's not a showstopper for me, but seems kind of silly. Maybe there's a good reason. You know, aside from increasing profit.

Technorati Tags: Google,T-Mobile,G1,Colin Walker

#Colin

Look out iPhone, Google and T-Mobile are the new kids on the block

Colin Walker — Tue, 23 Sep 2008 19:14:55 GMT

Google and T-Mobile have announced the release of the G1, the new smart phone that looks to be a serious competitor for the iPhone. RWW has a great article that lists some features and links to videos/images of the phone.

This touch screen, full QWERTY phone comes with Gmail, Google's Android OS, a lightweight browser, a full application market available, downloadable songs from Amazon with a single touch, and more. It's a pretty impressive offering, if you ask me, and just what I've been waiting for.

I've been looking to replace my Razr for a while now, but the iPhone never really caught my eye. This was largely due to the fact that it is 100% touchscreen, and it only runs on a network I'm not part of. The G1, however, solves both of those problems.

I'll see if I can get on the pre-order list and give you a full review as soon as I get my grubby little paws on it. It looks pretty impressive with fully functional browsing, smooth application flows from one to the next, and an actual keyboard that works for me. Pretty exciting stuff, if you're into the mobile computing thing.

Anywho, thought I'd share so you could take a look for yourself. Look. Discuss. And watch for updates as I'll track this thing to release and beyond. ;)

Technorati Tags: Google,T-Mobile,G1,iPhone,Colin Walker

#Colin

Taco Tuesday with Jason Hoffman, Joyent CTO

Colin Walker — Wed, 23 Jul 2008 19:09:39 GMT

So it looks like Joe and I are going to have to take a trip down to San Fran to check out Nick's Crispy Tacos with Jason Hoffman, CTO and co-founder of Joyent. Jason puts on a "Taco Tuesday" on the third Tuesday of just about every month. We've been invited down to check it out and geek out over the hawesome iRules/iControl/Ruby/*Nix/geeky stuff they're doing. Yeah...I'm not completely geeking out and excited, honest. Don't worry though, we'll try to make the best of it.

We got a fantastic opportunity today to talk with Jason about Joyent, what they're doing, their architecture, their background, etc. and how they're heavily leveraging F5 technology to make it all happen. For those of you that don't know, Joyent is a long-time F5 customer that provides a wickedly cool, scalable, flexible cloud infrastructure to users ranging anywhere from the Mom and Pop size to truly robust Enterprise level applications. You may have seen Joe's blog post about Joyent hosting LinkedIn's BumperSticker Facebook app that recently surpassed a billion page views per month. That spurred an offer to chat, and Jason was more than happy to oblige.

It was absolutely fantastic to talk to Jason who himself is an avid engineer that's got a long history with Unix and many of the flavors of coding that go along with it. As one of the first major adopters of Ruby and, in fact, the very first person to check in source to the Rails source control system, he definitely knows what he's talking about when it comes to *Nix programming, Ruby, and RoR. It turns out we even share a common love for and history with FreeBSD, go figure.

Over the course of our discussion we got to chat with Jason about his role at Joyent, what they're delivering to users, why it's unique and powerful, obstacles they faced along they way, how they got around them which, I'm happy to say, largely included F5 technology and specifically iRules and iControl, and many other such things impressively full of win. From many of their security policies relying on iRules instead of FireWalls, to iControl being an integral part of their provisioning system, to building iRules as solutions to countless customer problems or requirements, these guys are definitely power users and avid DevCentral members, I'm happy to say.

We also got to talk about the modern application, how it's architected, how the old school ways of thinking don't apply anymore and the massive benefits that can come from allowing yourself to see the possibilities with a modern, flexible, layered architecture. This architecture with powerful caches, application aware network devices serving large portions of the application functionality, and scalable, interchangeable back ends thanks to the load balancing that also occurs at that tier is hugely powerful and really more and more of a "must have" as things continue to progress in the application and application delivery world. Pretty darn cool stuff to hear from a PhD helping to run a hugely popular and successful hosting company. How's that for real world application?

This is the exact message I (we) have been pushing for a long time. Every time I talk about "preaching the good word", this is what I'm talking about. Times have changed, technology has improved, and F5 can be a big part of building a powerful, flexible, scalable, reliable architecture if you just let yourself think about things in the new, more modern world that Jason and Joyent have fully embraced. It's allowing them to be as powerful and usable as they are at extremely reasonable costs with incredible scalability as needed.

Check out the podcast to get more of the details. Obviously I'm excited, and am currently trying to refrain from a big squeeeee of geekitude, but that's just how I get when I get to riff about awesome technology with even more awesome people.

Stay tuned for the follow up where Joe and I tear into some tacos, margaritas and hopefully some iControl/Ruby/iRules with Jason down in his neck of the woods. Not that it's been approved yet or anything, but hey, I can hope, right?

Thanks again Jason for the great chat, and keep up the killer work.

Technorati Tags: DevCentral,iRules,iControl,Ruby,iContRuby,LinkedIn,FaceBook,BumperSticker,Joyent,Jason Hoffman,Colin Walker

#Colin

20 Lines or Less #10

Colin Walker — Thu, 26 Jun 2008 20:58:50 GMT

What could you do with your code in 20 Lines or Less? That's the question I ask every week, and every week I go looking to find cool new examples that show just how flexible and powerful iRules can be without getting in over your head.

With another three examples of cool iRules, this week's 20 Lines or Less shows even more things you can do in less than 21 lines of code. I still haven't heard much from you guys as to the kinds of things you want to see, so make sure to get those requests in. I can build all sorts of neat iRules if you just let me know what would be helpful or interesting. Otherwise I might just make iRules that make iRules. Scary.

This week we've got a couple forum examples and a contribution to the codeshare. Here's your epic, 10th edition of the 20LoL:

HTTP Headers in the HTTP Response

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&postid=25423&view=topic

Dealing with HTTP headers is one of the most common tasks we see in iRules. One of the things that I've seen floating about the forums and elsewhere lately is the question of how to access that information in the Response portion of the HTTP transaction. Some people have had a problem with this, as many of those headers no longer exist (like, say, the host). It's a simple solution though, as you can see below...just use a variable to get you there.

when HTTP_REQUEST {
# Save the URI
set uri [HTTP::uri]
}
when HTTP_RESPONSE {
if {([HTTP::header Cache-Control] eq "private, max-age=3600") and ($uri ends_with “.html”)} {
HTTP::header replace Cache-Control "public, max-age=3600"
}
}

Persistence equality in RDP sessions

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&postid=25271&view=topic

This example solves an issue with mixing Linux and Windows based RDP sessions across a persistence enabled virtual Apparently there's an issue with trying to persist based off of the user string as some clients include user@local.host and others just include the username. That's a bit of an issue. iRules to the rescue, as always.

when CLIENT_ACCEPTED {
TCP::collect
}

when CLIENT_DATA {
TCP::collect 25
binary scan [TCP::payload] x11a* msrdp
if { [string equal -nocase -length 17 $msrdp "cookie: mstshash="] } {
    set msrdp [string range $msrdp 17 end]
    set len [string first "\n" $msrdp]
    if { $len == -1 } { TCP::collect }
    if { $msrdp contains "@" } {
      if { $len > 5 } {
        incr len -1
        persist uie [getfield $msrdp "@" 1] 10800
      }
    } else { persist uie $msrdp 10800 }
}
TCP::release
}

Pool Selection based on File Extension

http://devcentral.f5.com/wiki/default.aspx/iRules/PoolBasedOnExtension.html

Taking a page from the codeshare, this iRule lets you build a correlation of file extensions and pools that serve those particular file types. This can be quite handy when dealing with large scale image servers, media systems, and especially systems that do things like dynamically generate watermarks on images and the like. Take a peek.

when HTTP_REQUEST {
  switch -glob [HTTP::path] {
    "*.jpg"        -
    "*.gif"        -
    "*.png"        { pool image_pool }
    "*.pdf"        { pool pdf_pool }
    default        { pool web_pool }
  }
}

There you have it; three more examples in less than 60 lines of code. I hope you're still finding this series helpful. As always, feel free to drop me a line for feedback or suggestions. Thanks!

Technorati Tags: DevCentral,iRules,20 Lines or Less,Persistence,HTTP Headers,Colin Walker

#Colin

iPhone for your ... club cards?

Colin Walker — Thu, 15 May 2008 01:39:47 GMT

We all knew it was inevitable. The iPhone was always bound for use by geeks and gadgeteers world-wide. That's no surprise. The iPhone continues to be used in new and interesting ways every day. The buzz has died down, but the geeks of the world haven't forgotten the craze and continue to find ways to use/promote/brag about this cool gadget. That's not so surprising to me, either. I know a fair amount of iPhone users and, while I'm not one of them, I can certainly see the draw behind not only the standard iPhone features, but some of the nifty add-ons the users find to use with it.

Just when I thought I'd seen all of the tricks, gadgets and tips for iPhone living, here's a new one for you. This article over at lifehacker describes a whole new way for using an iPhone that I never would have thought of. And this one DID surprise me. Check it out for yourself!

Club Cards ala iPhone, anyone? You know that stack of forty-eight cards you carry in your wallet? No, not the credit cards or the security cards to get into the Data Center, I'm talking about the club cards. You know, the cards you use at the grocery store, the book store, the gas station, and just about every other dang place it seems, these days? Well here's a solution to leaving them all at home, without losing the functionality.

I fully admit to having griped over the need to carry too many of these cards more than once. Sure, I could leave the card at home if I felt like reciting my phone number six times a day to strangers, in front of an audience. And yes, there are a few select places that will even keep these cards on file for you at the location you normally go to, but then what if you go somewhere else, and what about the vast majority that don't offer this service? How do I avoid the bulk and annoyance of a stack of these cards in my wallet without losing any of the functionality? Well, apparently, via the iPhone.

By scanning in the cards, and creating a photo album of them, a tricky user is able to easily tote his bagillion cards around in one sleek device that is likely carried anyway. And get this, the cards still scan as if they were physically present. Now there's something that not even iRules can do! Read about it over at lifehacker and get a chuckle, or inspiration, who knows.

Technorati Tags: iPhone,iRules,lifehacker,Colin Walker

#Colin

20 Lines or Less #1

Colin Walker — Wed, 09 Apr 2008 23:28:58 GMT

Yesterday I got an idea for what I think will be a cool new series that I wanted to bring to the community via my blog. I call it "20 lines or less". My thought is to pose a simple question: "What can you do via an iRule in 20 lines or less?".

Each week I'll find some cool examples of iRules doing fun things in less than 21 lines of code, not counting white spaces or comments, round them up, and post them here. Not only will this give the community lots of cool examples of what iRules can do with relative ease, but I'm hoping it will continue to show just how flexible and light-weight this technology is - not to mention just plain cool.

I invite you to follow along, learn what you can and please, if you have suggestions, contributions, or feedback of any kind, don't hesitate to comment, email, IM, whatever. You know how to get a hold of me...please do. ;) I'd love to have a member contributed version of this once a month or quarter or ... whatever if you guys start feeding me your cool, short iRules.

Ok, so without further adieu, here we go. The inaugural edition of 20 Lines or Less.

For this first edition I wanted to highlight some of the things that have already been contributed by the awesome community here at DevCentral. So I pulled up the Code Share and started reading. I was quite happy to see that I couldn't even get halfway through the list of awesome iRule contributions before I found 5 entries that were neat, and under 20 lines (These are actually almost all under 10 lines of code - wow!)

Kudos to the contributors. I'll grab another bunch next week to keep highlighting what we've got already!

1.) Cipher Strength of Pool Selection

Ever want to check the type of encryption your users are using before allowing them into your most secure content? Here's your solution.

http://devcentral.f5.com/wiki/default.aspx/iRules/CipherStrengthPoolSelection.html

  when HTTP_REQUEST {
    log local0. "[IP::remote_addr]: SSL cipher strength is [SSL::cipher bits]"
    if { [SSL::cipher bits] < 128 }{
      pool weak_encryption_pool
    } else {
      pool strong_encryption_pool
    }
  }

2.) Clone Pool Based on URI

Need to clone some of your traffic to a second pool, based on the incoming URI? Here you go...

http://devcentral.f5.com/wiki/default.aspx/iRules/ClonePoolBasedOnUri.html

when HTTP_REQUEST {
  if { [HTTP::uri] starts_with "/clone_me" } {
    pool real_pool
    clone pool clone_pool
  } else {
    pool real_pool
  }
}

3.) Don't Cache Posts

Have you been looking for a way to avoid sending those POST responses to your RAMCache module? You're welcome.

http://devcentral.f5.com/wiki/default.aspx/iRules/CacheNoPOST.html
when HTTP_REQUEST {
  if { [HTTP::method] equals "POST" } {
    CACHE::disable
  } else {
    CACHE::enable
  }
}

4.) Access Control Based on IP

Here's a great example of blocking unwelcome IP addresses from accessing your network and only allowing those Client-IPs that you have deemed trusted.

http://devcentral.f5.com/wiki/default.aspx/iRules/AccessControlBasedOnIP.html

when CLIENT_ACCEPTED  {
  if { [matchclass [IP::client_addr] equals $::trustedAddresses] }{
    #Uncomment the line below to turn on logging.
    #log local0.  "Valid client IP: [IP::client_addr] - forwarding traffic"
    forward
  } else {
    #Uncomment the line below to turn on logging.
    #log local0. "Invalid client IP: [IP::client_addr] - discarding"
    discard
  }
}

5.) Content Type Tracking

If you're looking to keep track of the different types of content you're serving, this iRule can help in a big way.

http://devcentral.f5.com/wiki/default.aspx/iRules/Content_Type_Tracking.html

# First, create statistics profile named "ContentType" with following entries:
#   HTML
#   Images
#   Scripts
#   Documents
#   Stylesheets
#   Other
# Now associate this Statistics Profile to the virtual server.  Then apply the following iRule.
# To view the results, go to Statistics -> Profiles - Statistics

when HTTP_RESPONSE {
   switch -glob [HTTP::header "Content-type"] {
      image/*         { STATS::incr "ContentType" "Images" }
      text/html       { STATS::incr "ContentType" "HTML" }
      text/css        { STATS::incr "ContentType" "Stylesheets" }
      *javascript     { STATS::incr "ContentType" "Scripts" }
      text/vbscript   { STATS::incr "ContentType" "Scripts" }
      application/pdf { STATS::incr "ContentType" "Documents" }
      application/msword { STATS::incr "ContentType" "Documents" }
      application/*powerpoint { STATS::incr "ContentType" "Documents" }
      application/*excel { STATS::incr "ContentType" "Documents" }
      default         { STATS::incr "ContentType" "Other" }
   }
}

There you have it, the first edition of "20 Lines or Less"! I hope you enjoyed it...I sure did. If you've got feedback or examples to be featured in future editions, let me know.

#Colin

It's not a sprint, it's a marathon...

Colin Walker — Tue, 25 Sep 2007 21:16:37 GMT

With the team's new push to make content for the community our first priority, it's turned into a veritable content storm around here! There are all kinds of new tech tips, videos, podcasts and more being posted every day.

But remember, "It's not a sprint, it's a marathon.".