DevCentral Top5 1/21/2011
Settling into the new year there is goodness a plenty on DevCentral this week. Between group revamps, site improvements and maintenance, including trimming the page size down to a more svelte, downloadable size, and the general content screaming across the front page there has been a lot to keep up on. Here are my Top 5 picks for the week to help you out:
Revisiting Hash Load Balancing and Persistence on BIG-IP LTM
As I may have hinted at last week, Jason had more tricks up his sleeve in regards to hash load balancing on the LTM. This week you get to see the full measure of his madness in all its graph-filled glory. What he’s doing here is basically testing how even the distribution across different members in a pool each different type of hash will be when used for load balancing. That’s right, folks, he’s finally answering the burning question of: CRC32, MD5, SHA, or CARP? I know to some of you ungeeks out there this might not be as exciting, but to us card carrying, calculator slinging, code dreaming geek types, this is wicked cool. To get a fair comparison Jason whipped up a couple of scripts in python and tmsh, an iRule for the testing results, and output some pretty graphs that show the results. Go take a read through and see if you can keep up with Jason’s mad skills (here’s a hint: most people can’t), and get a look at the power of iRules and hash LB on the LTM.
10 Ways to HA (and counting): a treatise on BIG-IP high availability
Kevin Stuart, one of the engineers in the field here at F5, put up this interesting post on different ways that BIG-IP helps you maintain an HA environment. It caught my eye enough to make the Top5 because he goes through each of the different “10”* (*note there are 14 in the “10 ways” list…) ways and explains each of them. It’s an interesting walk through the many ways that we take for granted that these kinds of environments and systems can work to keep an application up and running. Most of this stuff we don’t even think about when relying on a device like LTM, but it’s actually really cool to see things like session state sharing, session mirroring and shared MAC addresses called out in a list of important features. It’s doubly cool that he explains why. Take a read, this one’s a light refresher course after the heavy science Jason dropped in the link above, but no less interesting.
Is There Such A Thing as a Safe Area of the Web?
While Lori might not provide the answers to all of your security problems here, she certainly states a firm reminder, summed up in a sentence that I’ll just quote, since I have no hopes of saying it better myself, “Just because your house hasn’t yet been broken into doesn’t mean you stop locking your doors.” In her post she addresses the question posed by a member of the twitterverse about whether or not they truly need anti-virus software anymore. They aren’t getting any virus alerts, they’re technologically savvy and careful what they browse and click, and are up to date on all the latest patches…so is an active AV really needed? Well no, I suppose technically it’s not. Neither are seat-belts in a car when you get right down to it, but I feel better knowing they’re there if I need them unexpectedly. This one’s a good reminder that even though you’ve gotten good at being as safe as you can on the web, there are many bad people doing many bad things, and you’d rather they didn’t do them to your system. So stay safe, after you read the post of course.
Rate Shaping: An Old Trick You Might Need Soon.
Don put out an article this week that contains a single statistic that, if you stop and truly absorb it, is equal parts exciting and sobering. That is that, according to Ericsson, mobile broadband subscriptions will double in 2011. While I take into account that this is a provider involved in the broadband world saying things about broadband subscriptions, I’ve heard similar things from many sources, and the numbers are all somewhere in that neighborhood. Think about that for a minute. Two times the mobile users, two times the mobile internet traffic, two times the mobile user accounts, two times the authentications, SSL handshakes, etc. So either get busy doubling your infrastructure, or start thinking of ways to get the most out of what you already have. One of the many available avenues of doing just that, is the subject of Don’s post: rate shaping. This is an interesting read to get the ole’ brain working on a problem that seems likely to rear its head as the year presses on and traffic grows.
20 Lines or Less #43 – Nesting, Rewriting Redirects and Auth
Here we are again, with the 20 Lines or Less. In case somehow you’re not familiar with the format, the idea is to show off three examples of iRules doing the cool things that iRules can do, each in less than 21 lines of code. I love the series, and this week I’ve got more examples of iRules goodness for you to sample, share, implement, or twist to whatever your whims may be. This week I feature a couple forum posts, one on properly nesting a switch inside an if, one on how to properly re-write redirects using a class and some string trickery, as well as a Tech Tip George wrote a while back on authentication via iRules that somehow never made it into the 20LoL. I hope you enjoy.
That does it for this week’s Top5. Let me know if you’ve got any comments, questions or otherwise. Otherwise thanks for reading.
#Colin