Sean's Blog

VW and Audi alike make great ads. And have for quite some time,...

Sun, 12 Feb 2012 17:16:00 -0500

VW and Audi alike make great ads. And have for quite some time, it seems.

I want one so badly. The way it was being flicked around on the...

Sat, 11 Feb 2012 13:19:53 -0500

I want one so badly. The way it was being flicked around on the track reminds me so much of my 240.

Favorite song of the album, I think. Seems pretty good live too,...

Sun, 29 Jan 2012 11:58:03 -0500

Favorite song of the album, I think. Seems pretty good live too, as best as I can tell from this…

Drool.

Sat, 28 Jan 2012 12:14:42 -0500

Drool.

Highly Available, Multi-Site MySQL

Sun, 22 Jan 2012 15:22:00 -0500

I’ve been playing with designs for this lately, and it’s been interesting, given some of the following considerations:

The applications in question are (relatively) low volume, low transaction applications.
Only one site will be active at any given time.
Delays of 30 seconds or so are acceptable in case of failure within a site.

With that in mind, I’ve been playing with MySQL+Heartbeat/Pacemaker/Corosync+Multi-Master replication. MySQL + Heartbeat/Pacemaker/Corosync gives redundancy within a site, utilizing shared storage (though I could throw DRBD into the mix as well, though for little benefit). Multi-master replication allows for asynchronous replication between sites (hundreds of miles apart—high bandwidth but also relatively high latency) without impacting performance.

The one portion I was a little unsure about was how the MySQL replication would act when connecting to a VIP shared between two systems at a given site, but it seems to work just fine. I’ve got some more testing to do (quite a bit of testing, to be honest), but this should make my life (and job) relatively easy.

As a bit of an aside, MySQL multi-master replication does extend beyond two hosts, but it’s circular in nature. If you have four nodes (A, B, C, and D), your replication goes from A to B, to C, to D, and back to A. If you lose, say, node B, your replication is completely broken. This page includes a very, very clever use of stored procedures to work around this, but as ingenious as it is, that violated the KISS principle a bit too much for my tastes.

MacBook Air Thoughts

Sun, 22 Jan 2012 15:06:51 -0500

It’s been a few weeks with my MBA now, and I have a few more thoughts:

The screen on the 13” model could just a bit bigger, with more pixels. Its 1440x900 resolution is pretty good (and better than most Ultrabooks—their biggest shortcoming, in my opinion), but the bezel is large enough that it could—and should—be enlarged a bit.
It’s nice and thin. It could have been made a marginal amount thicker to add in an Ethernet, and maybe even a FireWire port, and no one would have objected. The thinness is really just for bragging rights—and not much else.
My last MBP ran under $2,000. To get a 15” MBP that’d blow my Air out of the water (i.e., with a 256 GB SSD, higher resolution display, etc.), you’re talking about $2600 or so. Yes, it’d have two more cores, and far better graphics, but 99.999% percent of people wouldn’t be able to tell the difference. Apple has gaps in their product lineup like no other tech company—and they just don’t care.

I can’t get this out of my head, and I don’t...

Sun, 22 Jan 2012 12:38:14 -0500

I can’t get this out of my head, and I don’t necessarily view that as a bad thing. I hear a little bit of The Cure, The Killers, and some of their more humorous lyrics remind me a little of Third Eye Blind even (on their latest album as a whole, not necessarily in this song).

Steve Jobs' Biography

Sun, 15 Jan 2012 13:05:41 -0500

I finally got around to reading Walter Isaacson’s biography of Steve Jobs, and overall, it was pretty good, with a few caveats. A great deal of it will be very familiar to anyone who has read Owen Linzmayer’s “Apple Confidential” (which I can’t recommend highly enough to anyone with any interest in Apple’s history), and there are plenty of Jobsian anecdotes that you can find on the web that are just as interesting as anything in the book. Specifically, stories you can find here come to mind.

The one thing that kept bothering me about the book was Isaacson’s attempts at being objective, where I think he failed to varying degrees. I think he did a fine job of presenting Steve Jobs as a man, with all the good and all the bad, but I also think he—along with the vast majority of people, really—gives Jobs too much credit for a lot of things.

Make no mistake—Jobs was a perfectionist who was fanatical about making sure his companies’ products (whether at Apple, Next, or Pixar) were as polished as could be. This fanaticism played a big role in the success of things like the iPod and iPhone, but people also look at him as an innovator. And that’s where I have a problem, because Jobs was about as far from an innovator as you could possibly get (in my opinion).

The Mac was not the first computer with a GUI, and even when it did come out, it (arguably) wasn’t the best GUI out there. The iPod wasn’t the world’s first MP3 player. I had a Rio long before the iPod came out, and aside from a lack of storage (which I admit returning it for—the solution for that particular issue would have come with or without Apple), it was pretty damn good. The iPhone wasn’t the first smartphone with a touchscreen. The iPad wasn’t the first tablet. Apple arguably had the iPhone and iPad before those products even came out with the Newton. Which Jobs promptly killed upon his return to Apple before the “innovation” of the i-products.

I’m not necessarily trying to take anything away from the man, or Apple. Their products are generally pretty damn good, and Jobs was a big reason for that. But, just about anything Apple did was done by others before them. Jobs and Apple made the world a better place, but not through innovation. Instead, it was evolution and polish.

It’s an important distinction to make, and one that I think Isaacson understood in his head, but was altered in print by the infamous RDF. The folks who came before Apple tend to be forgotten, but without them, Jobs and Apple alike could have never gotten to where they were/are today.

religiousragings: How to Save the American Economy

Mon, 09 Jan 2012 20:22:03 -0500

religiousragings:

How to Save the American Economy

A Few More Apple Things

Sat, 07 Jan 2012 17:39:00 -0500

I already ordered a sleeve and “ScreenSavr” from RadTech. They look nice, and should suit my OCD-ness quite well. It’s particularly important now that my laptop will actually get used on my lap (instead of sitting on my desk with an external LCD, keyboard, and mouse attached to it at all times).
I’ve wanted a truly dockable Mac for years, and Thunderbolt should make that possible (mostly). Well, it’s already possible if I wanted to drop another grand on Apple’s 27” display, but I think I’ll wait for this instead.
It might be time to upgrade all the wireless access points throughout the house to ones that support wireless N.
A MBA with 8 GB of RAM will come out the day after my return period expires. Guaranteed.
Full screen mode kicks ass for Terminal. Don’t really need it for anything else.
Who the hell buys iPads when you can get a MacBook Air instead?

New Computer Time

Sat, 07 Jan 2012 15:23:00 -0500

It was about a year ago that I bought a used ThinkPad off eBay, and with that, I started to think my Mac days were nearing an end. The hardware is still top-notch, but I had serious questions about their commitment to OS X, as well as whether or not the changes to the OS were positive ones (or just attempts to turn it into an iOS clone, which is not a compliment).

With my MacBook Pro nearing 4 years old, it had started feeling a little slow (mostly owing to its hard disk, honestly), and I had never really used it as a laptop anyway, so I started considering my options. In the end, I was between a brand-new ThinkPad T420S and a 13” MacBook Air (in both cases with a SSD—having one in my computer at work has spoiled me). As tempted as I was to go with the ThinkPad, I’m trying out a MacBook Air instead.

And so far, so good. The ThinkPad I have is great for a lot of things, but it’s a tad too small to be a primary computer. My MBP is just a bit too big. The 13” MBA (with the same resolution as my 15” MBP) is just about perfect. I didn’t opt for the i7 option, but the i5 is plenty fast enough, particularly in conjunction with the SSD.

Lion is a bit of a change, and I’ve gone through and reverted just about everything I can do the Leopard/Tiger way (scrolling direction/bars, Dashboard, Exposé, 2D dock, etc.). The under-the-hood improvements since Tiger have generally been great, but the UI changes have been mostly shit, in my book. I’ve said it before, and I’ll say it again here—on the OS front, Apple’s lead over Microsoft is marginal at best, and their attitude towards perfection in consistency is rapidly disappearing.

But all in all, it’s still phenomenal hardware, and the OS—once its default flaws are fixed—is still just a little nicer than Windows Vista/7. Plus, I’m a UNIX geek at heart, and I love having a bash shell just a Terminal click away (yeah, yeah, yeah… I know all about Cygwin. It’s not the same.).

This guy (Bryan Cantrill) is awesome. Larry Ellison is the...

Mon, 26 Dec 2011 15:41:00 -0500

This guy (Bryan Cantrill) is awesome. Larry Ellison is the devil. Proof of both in just over a hour, objectivity aside.

Recycling RSA Appliances

Mon, 26 Dec 2011 13:44:34 -0500

RSA hasn’t gotten a whole lot of great publicity in the past year, and rightfully so. However, the old SecurID appliances (the ones with LCDs on the front panel) are pretty nice and recyclable systems. I’m specifically referring to the ones where RSA sourced the boxes from Celestix. They’re pretty much standard x86-based servers that don’t consume a whole lot of power, and can run any OS you want without much trouble.

We replaced our RSA boxes at work earlier this year, and we were getting ready to throw two of the old ones away. So naturally, I adopted them and brought them home. One of them has already replaced an ancient Gateway (366 MHz Celeron) box, and the other (with 4 NICs on-board) is poised to replace my little ALIX firewall (hardware-wise, it’s very much like the step between an ASA 5505 and a 5520).

If only the driver/controller software for the front-panel LCD were available (source code or otherwise), I’d have them saying “PC LOAD LETTER” in no time.

My Next Car

Mon, 05 Dec 2011 21:03:00 -0500

My Next Car:

My 1990 Nissan 240SX was 2,684 pounds, with a 2.4 liter truck engine making a measly 140 HP, with a 5-speed manual. It was boatloads of fun though, with a perfectly chuckable, well-balanced RWD chassis.

This 2013 Subaru BRZ (and its Toyota/Scion sister) looks to come in at 2,689 pounds, with a 2.0 liter flat-4 making 200 HP (about what my GTI does), with a 6-speed manual. And while I haven’t driven it yet, I’ve seen plenty of video to know that I’ll look forward to giving it some opposite lock fun.

Nissan, I don’t care if the 370Z has a lot more power. Hyundai, I don’t care if your Genesis Coupe looks better (arguably). Ford, as much as I once enjoyed one of your Mustangs, it was no sports car. Subaru and Toyota, you may just have one more buyer whenever you get this thing in showrooms…

I was working in our new office this week. It has two gigabit...

Sat, 03 Dec 2011 11:28:15 -0500

I was working in our new office this week. It has two gigabit Internet circuits. The speed test site couldn’t quite keep up…

Never thought the Pope and Joe Paterno would have so much in common.

Sun, 13 Nov 2011 13:19:12 -0500

If he had been Father Sandusky, I’m guessing he would’ve had at least another 20 or 30 years before anything was done about it.

ben: At MoMA A SE/30 that still boots off a 100 MB Zip...

Sat, 12 Nov 2011 12:17:27 -0500

ben:

At MoMA

A SE/30 that still boots off a 100 MB Zip disk sits in my parents’ basement. One of the first computers I ever used.

the_real_netflix

Mon, 10 Oct 2011 21:23:33 -0400

the_real_netflix

Dear Volkswagen

Sun, 02 Oct 2011 17:47:01 -0400

1. Could you please stop using triple square screws/fasteners all over the place? They’re a pain in the ass to work with, and difficult to find bits for. Tell your German friends too, please.

2. If you are going to continue to use triple square screws/fasteners, could you please not use friggin’ gorillas to tighten them up? When a caliper carrier is held in place by two 14mm triple square screws that are supposed to be torqued to 90 N-m, I should be able to easily break them free with a 18” breaker bar. And even if the breaker bar weren’t enough, PB Blaster and a rubber mallet should have been. But no, you just had to tighten the shit out of these things. Stop that shit!

3. If you are going to tighten the shit out of these screws, could you at least not put them in spots where it’s nearly impossible to get a bit and breaker bar on them? You know, the little things, like not putting the shocks, the springs, and the brake lines in just about every position you could get a breaker bar, or even a socket wrench in there?

4. Lastly, if you’re going to put nifty electronic sensors on the car to tell you when the pads are nearly worn completely, would you consider putting them on the axle that wears the fastest? It used to be the front, but these days, it seems to be the rear. Move the sensor there then.

It took me 15 minutes to jack up the car, pull the wheel, remove the caliper, and put new pads in. I spent hours (before loading up with new pads) trying to get the two 14mm triple square bolts off, so that I could pull the rotors. Ridiculous.

I love my GTI, but it really can be a pain in the ass to work on (which is probably true of most modern cars, to be perfectly fair, but still).

FCoE Woes

Sat, 17 Sep 2011 14:47:00 -0400

We’re building out a few new datacenters at work now, and before I can get a start on the Linux infrastructure, we’ve been working on the core infrastructure (network and SAN). We’re fortunate in that we’re able to use some of the latest-and-greatest technologies, including some nice new 10GigE switches that support FCoE, along with necessary CNAs (converged network adapters).

What makes these really cool is your NICs and HBAs are now one in the same. For a given level of redundancy and bandwidth, your port count is cut in half. And with these fancy Twinax cables/transceivers you can get, you don’t need to use fiber to leverage these benefits.

Of course, nothing’s perfect. I haven’t been working on the networking side of things too much, but it looks like it’s been quite a pain to architect the design of what will be a truly converged network, with a pair of switches providing redundant network and fabric connectivity to the SAN (requiring things like VPCs, etc.).

Among the things I’ve noticed is the difficulty of getting the NIC side of the CNA bonded on Linux. Let’s say you configure a switch from a certain vendor whose name rhymes with Crisco such that you have “channel-group XXX mode on” for each port. Great. You can boot from SAN just fine, and all the stuff on the FC side works just fine. But no networking. OK, you figure. Let’s try “channel-group XXX mode active” on each switch port, and then configure LACP on each host. Yeah, don’t do that. It’ll get networking going, but it’ll break FCoE connectivity, which especially sucks when your OS volume(s) are stored on the SAN.

As best as I can figure it, no CNA on the market today (and perhaps the FCoE standard itself) allows for LACP to be configured at the adapter level. Naturally, my first thought was to try active/passive bonding at the Linux level instead, but that didn’t work. Inexplicably, a vendor suggested we try XOR load balancing (mode=3 when you load the bonding module), and that managed to get things working.

As nice as it is to cut your necessary port count in half, it’s kind of scary when you’re putting everything (network and storage) in one bucket. Especially when the documentation hasn’t quite caught up to the technology.