Goodness it's been a while since we've had a Top5, hasn't it? The past couple months have been insane for vacations/medical leave/paternity leave, etc on the DC team. Hopefully things are settling down now, and we can get back to our normal routine. Regardless, here I am, your faithful guide through the oceans of content on DevCentral, committed to bringing you a weekly sampling of the Top5 coolest new things that showed up on DevCentral. Even with parts of the team out, there's been lots of content, so buckle up, here's your Top5:

Dear Data Center Guy

http://devcentral.f5.com/weblogs/macvittie/archive/2008/08/29/3572.aspx

Sometimes the things I pick for the Top5 are the most informative pieces I can find. Other times they're the most exciting and interesting because of some new announcement or content. This one is, well, just plain hawesome. Go check out Lori waxing away from the perspective of a lonely, forlorn BIG-IP. Follow this plea to the "Data Center Guy" and find out why it is that there's more than meets the eye to the BIG-IP, and why it's worth investing some more time getting to know yours.

Crack open the books, it's iRule time

http://devcentral.f5.com/weblogs/Joe/archive/2008/08/29/crack-open-the-books-its-irule-time.aspx

Exciting news from the training group! F5's stellar training team now officially offers and is booking iRules training! This is fantastic news. Up until now the aspiring iRuler had to rely only on their wits, their browser, and the ever-faithful DevCentral. Now there's an organized, formal way to get some hands-on, classroom instruction to get your iRuling experience jump started. This is something that's been a long-time request of the DC members, and I'm very, very pleased to be able to share this great news. Make sure you take a look and read the course description for more info.

iControl Apps - #08 - System IP Statistics

http://devcentral.f5.com/Default.aspx?tabid=63&articleType=ArticleView&articleId=264

Check out Joe flexing those iControl muscles yet again in this continuation of the iControl Apps series. In this edition Joe will walk you through how to query yet more fun statistics type stuff (very technical term) from the BIG-IP via iControl. If you ever wondered how to get access to aggregate, IP based statistics in a programmatic fashion, well, then this is the one you've been waiting for. Even if that hasn't been your dream since high school, this post is definitely worth checking out for more firepower to add to your iControl arsenal.

20 Lines or Less #14

http://devcentral.f5.com/weblogs/cwalker/archive/2008/08/29/20-lines-or-less--14.aspx

In our second week back on track with the 20LoL I manage to find still more cool examples of iRules fu that are byte sized at most. In less than 21 lines you can learn how to distribute email to the appropriate pools based on IP address. If that's not enough, we're doing HTTP inspection without HTTP profiles, too. Confusing? It won't be if you click through and take a gander. Good ole' TCP commands to the rescue. Take a peek, send some comments, add a suggestion.

DevCentral Weekly Roundup Episode 52 - The Road to 100

http://devcentral.f5.com/weblogs/dcpodcast/archive/2008/08/29/3575.aspx

Last, but never least, is this week's DevCentral Roundup. This is a special edition of the podcast this week, because this week we wrapped up our 52^nd chat about DCLand, IT in general, and all sorts of other wacky stuff. With a year's worth of podcasts behind us, it's time to set our sights on 100 and keep on trucking, because there's plenty to talk about every week, that's for sure. This week listen to Don and Joe talk about all sorts of cool iControl applications and twitter and the like, and Colin try to keep up and explain that he's almost caught up from being out for 3+ weeks….honest. The Roundup is always a great way to get a dose of what we've been up to in a short amount of time, without even having to do any of that reading stuff. Have a listen and let us know what you think.

There you have it, your Top5 for this week from DevCentral. It's good to be back, and hopefully you faithful readers out there have been eager for this to get fired back up. If you've got questions or comments please feel free to drop me a line, as always. See you next week.

#Colin

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.

This week we've got three more fun examples of iRules goodness for you, thanks to the awesome community driving the forums and the CodeShare.  As always the goal is to show off some of the things that you can do with iRules in less than 21 lines of code. Let's dig in:

Distribute Email by Source IP

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

From the wiki comes this handy showcase of pool switching based on IP address. Putting this to good use by distributing info to different mail pools is an even cooler idea, which is just  what this iRule does.

when CLIENT_ACCEPTED {
   if { [IP::addr [IP::remote_addr] equals 10.2.0.0/255.255.0.0 ] }  {
     log local0. "Node IP address is: [IP::remote_addr] and sent to SMTP_clients_from_10.2"
     pool smtp_clients_from_10.2
   } else {
     log local0. "Node IP address is: [IP::remote_addr] and sent to SMTP_clients_from_elsewhere"
     pool SMTP_clients_from_elsewhere
   }

}

String Based HTTPS Redirect

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&postid=26517&view=topic

Yet another cool twist on the simple HTTP redirect iRules we've talked about before, this one uses a Location header in the response as well as a class of URIs to pick from. Even though it's a variation on a theme, it's cool to see the ways people are doing things, and remind us all that we have LOTS of options when it comes to iRuling.

 when HTTP_REQUEST {  
    switch -glob [string tolower [HTTP::uri]] {  
      "*alumni/giving/gift/" -  
      "*alumni/giving/pledge/" -  
      "*alumni/directory/search.aspx" -  
      "*alumni/directory/update.aspx" {  
      # don't do anything... 
      }  
    default { 
       HTTP::respond 301 Location "http://[getfield [HTTP::host] : 1][HTTP::uri]"   
      } 
    }  
  }

HTTP Routing without HTTP Profile

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&postid=26569&view=topic

This one is super cool (assuming it works..note that it's untested, but I like it anyway!). The issue here was that the user needed to inspect some HTTP information in a session without applying an HTTP profile to the Virtual Server. That means no HTTP:: commands. Oh no! Never fear, TCP::collect to the rescue!

 when CLIENT_ACCEPTED { 
   TCP::collect 
 } 
 when CLIENT_DATA { 
   set idx [string first " HTTP/1." [TCP::payload]] 
   if { $idx < 0 } { 
     if { [TCP::payload length] > 2048 } { 
        log local0. "ERROR! Could not find HTTP request in 2K! dropping..." 
        reject 
     } else { 
       # Not enough data yet; collect more 
       TCP::collect 
     } 
     return 
   } 
   set request [string tolower [TCP::payload $idx]] 
   log local0. "Got request: $request" 
   if { $request contains " /XXXXX" } { 
     log local0. "Sending to Pool_XXXXX" 
     pool Pool_XXXXX 
   } else { 
     log local0. "Sending to Pool_WWWWW" 
     pool Pool_WWWWW 
   } 
 } 

Hot off the presses, that's this week's 20LoL. Tune in again next week for even more iRule endeavors.

#Colin