Category Archives: Technology

Usenix

Technology

Well, we’re back from the Usenix ’06 Annual Technical Conference. Overall, a very nice conference. This is the first Linux/Unix conference I’ve been to since the old LinuxExpo (NOT LinuxWorld) events in the late 90s.

I must say it was quite fun to be around so many intelligent *nix folks. I learned quite a bit, and learned how much I had in common with some (and how little with others). A very nice social at the New England Aquarium Friday night.

Some very interesting speakers, too, with lots of experience to share. I’m glad I was there.

I have only one main complaint about Usenix — they tried to cram too much into too few days. The conference sessions ran till as late at 6:45PM, with BoFs after that. That left almost no time to see anything of Boston and meant that very few people could actually stick around for all the BoFs. Next year, they should use more days and schedule fewer things in the evenings.

The highlight of the trip, though, wasn’t Usenix at all, but instead getting to meet some Boston-area Debian folks Saturday night. Lots of fun, and Mako is as crazy in person as he looks online :-)

Our train trip in each direction was nice, too.

More to come…

Why I Like HP

Hardware

I’ve been managing servers professionally for some years now. Support is one of the most important things when you are managing computers for work. You don’t need support to help you out with a printing problem or an e-mail problem. You need support because every minute the machine fails to power up, your company may lose twice the value of the entire machine. Or even more.

My first day job managing servers involved Dell hardware. What a nightmare. I’ve never had a good experience with Dell support, ever.

First off, Dell support never puts me straight through to an intelligent support rep. I don’t care whether I get to the Indian call center or someone in Texas. The first support person I speak to at Dell has less computer aptitude than my grandmother. One conversation I will always remember went like this:

Me: We have a disk in our array that went bad on our Linux server. The red light on the disk itself is on. Please send us a replacement.

Dell: Have you tried rebooting?

Me: No. This is a production server. The reason the disks are redundant is so I don’t HAVE to. Besides, the light ON THE MACHINE ITSELF is on.

Dell: Ah, OK. Have you run scandisk?

Me: No. This is a Linux server, as I told you, and scandisk wouldn’t see a problem anyway since this disk is in an array and the array is still up.

Dell: OK, great. How about you download the diagnostics .exe from our website…

Me: Can’t. We don’t have Windows on this machine. You did say you support Linux when we bought it.

Dell: Ah. Can you right-click on My Computer…

Me: NO. This runs Linux, and the BAD DISK LIGHT ON THE MACHINE IS ON.

Dell: Ah, OK. I wonder if the problem really is that you have a bad disk.

Me: Could be!

Our first HP server purchase happened to be at a time when HP had undercut Dell by several thousand dollars. I liked the hardware, but it wasn’t anything that much more special than Dell.

But what I really like is the support. I haven’t had to call HP support often, but when I do, I am almost always speaking to a live, experienced person within 5 minutes.

With only one exception, all the HP support people I’ve talked to have been very experienced. They all sound like they’ve been working with HP hardware since the late punched card era. They know what is going on and assume that I do too. The HP people don’t make small talk (it *really* ticks me off when someone obviously in Calcutta or something asks me about the weather in Kansas, because you *know* they are reading it off a screen and don’t care). But that’s fine. I’m not calling them to talk about the weather, I’m calling them because my server is down.

We had a bad disk in an array on a HP server once. That conversation went more like this.

HP: Server support. Serial number please?

Me: [gives it to them]

HP: OK. What’s the problem?

Me: The array dropped a disk. The failed disk light is on and the controller logged a disk error.

HP: OK. That’s a 146GB SCSI, right? 15KRPM or 10K?

Me: 15K.

HP: OK. Is 1PM tomorrow good to send out the replacement?

Me: Fine.

HP: OK, your case number is xxxxx. Can you give us directions to your location?

Me: Sure…

So recently we got in our MSL4048 tape library. A very nice unit. And faster than most *disks*. 48 Ultrium3 tapes — 400GB native each — very nice. And a barcode reader built in.

So anyway, one small problem. When you open up a magazine to put tapes in, you can close the unit back up. It says “scanning”, but it doesn’t notice that we’ve changed tapes until we give it a command on the operator panel (yes, this tape drive has a LCD screen built in). This can be worked around, but is annoying and is just waiting to cause confusion. Plus it’s not how it should work.

So I call HP support yesterday.

Turns out this MSL4048 is a brand-new unit. Had only been on the market a few weeks. Our support rep has never seen one or taken calls about one, and they haven’t even given him all the HP technical docs yet. But no matter, he is willing to try to help us out.

He calls me back twice yesterday with tips and questions after speaking to colleagues. He asks intelligent questions, doesn’t bother with the “are you sure you’re putting the tapes in the right way around” or the “is the power cord securely plugged in” crap, and generally doesn’t waste my time. He called me back about four times more today — they duplicated our setup in their lab, right down to the exact firmware version, but didn’t have the problem. Two of those callbacks were apologizing for taking so long, and explaining that they were learning about this machine as they went along. So a HP rep will be out to our location shortly.

Now THAT’S what I call service. No blaming it on someone else, no trying to make me do stupid troubleshooting things, and returning calls.

My *one* bad experience with HP was one time we put a new internal tape drive in the machine, and it was acting flaky. I got the only not-very-experienced HP rep I ever had spoken to that time, and they tried to blame Debian for what turned out to be a bad SCSI cable. (The symptoms weren’t very similar to what I’d expect for a bad SCSI cable, and the cable had been working fine.) Oh HP, you donate to Debian — why don’t you support your hardware under it?

(In fairness, that is the ONLY time they have flinched when I said I run Debian, though it does make them hesitate sometimes)

Bacula

Software, ,

Lately we’ve been looking at backup solutions at work.

And I’ve got to say that Bacula is looking downright awesome. It’s GPL’d and it has just about every feature a person could ask for.

I am a complete Bacula newbie. Today, after using Bacula for a total of about 30-60 minutes, I added the first client machine to my Linux test box. The client machine was running the Windows bacula client. It took about 10 minutes to install and configure the client and the server. And both backup and restore worked perfectly the first time. Nice. Setting up a *nix client is even easier.

I’ve been using Amanda for many years at home and at various workplaces. Looks like we’re going to be switching.

We’ve also ordered an HP MSL4048, a 48-tape LTO3 library with barcode support. Each tape has a native storage capacity of 400GB. Should be nice when it arrives. With that library and Bacula, we should be able to back up all our servers using a single backup system. And both our Windows and Unix people can manage the system, including running restores to any machine, from any authorized console machine.

Debian From Scratch 0.99.0 Is Out

Debian

At long last, I’ve finally updated Debian From Scratch (DFS). For those of you not familiar with DFS, it’s a single, full rescue CD capable of working with all major filesystems, LVM, software RAID, and even compiling a new kernel. The DFS ISO images also contain a small Debian mirror subset that lets you use cdebootstrap, along with the other utilities on the CD, to perform a manual, “Gentoo-like” installation. It also serves as an excellent rescue CD, with a full compliment of filesystem tools, backup/restore software, and a development environment complete enough to build your own kernels.

DFS also refers to dfsbuild, the tool that generates DFS images. dfsbuild is available as a Debian package. dfsbuild is designed to make it trivial to build your own custom DFS images. You can have your own set of Debian packages on your images, your own kernels, etc. Unlike many other systems, you can go from the example dfs.cfg to a customized DFS build in just a few minutes, even if you’ve never used dfsbuild before.

Version 0.99.0 is a from-scratch rewrite and port to Haskell. You can read the full list of new features in the announcement, but the biggest is that it now supports standard Debian initramfs kernels in addition to ones that have enough drivers statically linked to be able to read the CD-ROM.

You can also download my DFS images or browse the docs online.

Dupes really fixed now

Software, , ,

Thanks to some assistance from Garvin (lead Serendipity developer), it looks like the bug that Planet dislikes so intensely is indeed the <slash:comments> tag. I don’t believe this is a bug in Serendipity bug rather in Planet.

(There is still, IMHO, a pubDate bug in Serendipity, but it appears to be unrelated)

So, the dupes you were seeing from me really are gone now. I hope.

The fix is to edit the file templates/default/feed_2.0.tpl and remove the line that provides the <slash:comments> tag.

BTW, seems that Planet Haskell also ran afoul of this.

Sorry for the dupes

Software, , ,

It seems that some of my posts are appearing on Planet Debian multiple times, and others not at all. I think the problem is a strange combination between subtle bugs in Planet and Serendipity. The SF bug report for Serendipity is here. I think the workaround should fix this.

Either that, or Planet is somehow taking offense as the <slash:comments> tag that Serendipity is putting in there.

Sorry about that — hopefully it is fixed now.

Mail Server Comparison

Humor, Software, , ,

After my mail reader comparison, I’ve been fortunate enough to have a few mail server troubles. So here, to help you with your mail server decisions, is my mail server comparison.

  • Postfix: Your mail can now have the distinction of being deleted by 53 individual subservers
  • Sendmail: Priority treatment if you can write, while holding down your Shift key, an m4 macro to calculate the airspeed velicoty of an unladen swallow. All other messages will be summarily deleted in 6-8 weeks, or whenever the queue daemon catches up, whichever is later
  • Exim: Conveniently marks every message as “unrouteable” to reduce the hassle of making up reasons to bounce mail
  • Courier: Promptly delivers, but then quickly hides, all mail
  • Qmail: Might actually receive mail from DJB. The rest of the world will receive rude, copyrighted bounce messages.
  • Exchange: Storing mail is irrelevant since the server isn’t up often enough to actually receive any. This server is also perfectly secure unless it is running.

Switched to Serendipity!

Software, The ChangeLog, ,

Well, finally! I’ve switched to Serendipity!

The best part: comment spam blocking that works. So to those of you that had trouble commenting on this site… try again. It should just work! (And I’m sorry you had to put up with the hassle so long.)

Serendipity is a very nice system. I’m glad I chose it. And the support from Garvin and the others has been great too.

I’m running 1.0beta2 and have found a few bugs, but nothing serious.

As I mentioned before, I wrote a tool in Haskell to convert posts, comments, and categories from Drupal to Serendipity. If you use darcs, you can fetch it with:

darcs get --partial http://darcs.complete.org/unmaintained/blogcvt

The darcs-impaired may download a tarball.

I’ve chosen Serendipity

Software, The ChangeLog

I wrote the other day that I was considering Serendipity, and had a few concerns about it.

Those concerns have now been pretty well resolved.

I also looked at WordPress. It looked like it had more features, but the whole lack of a central plugin store bothered me. I’d have to scour all over the net to find plugins, and half of them are just on a random person’s blog. Very few mentioned support for WordPress 2.0; most were for 1.5.

Then I looked at anti-spam options in both. The major anti-spam plugin for WordPress had two big strikes against it, in my mind: it’s not Free software, and it doesn’t work with PostgreSQL.

I am really ticked off by webapps that only support MySQL. There is no reason not to support PostgreSQL (especially when WordPress itself does).

So I am going with Serendipity.

Now, I have to write a Drupal to Serendipity conversion tool.

Initial thoughts about Serendipity

Software

I downloaded Serendipity 1.0beta2 over the weekend and started trying it out.

My initial thought after setting it up was: *wow*. It really is incredibly easy to set up. No hand-editing of config files. No weird menus or scattering things all about. The whole system speaks of elegance and good coding practices. Except the fact that it ships some files world-writable in the tarball.

As I looked at it some more, I noticed a few problems, though. I submitted bugs or feature requests to the project as appropriate, and am including links to them here:

  • No option to display the number of reads for each story. SF 1459385
  • No tracking of HTTP referers (or, at least, no integrated interface for viewing them). SF 1459389
  • Spartacus, the tool to automatically download and install new plugins over the Web, was broken. The netmirror.org site was unresponsive and the s9y.org site gave a 404 to it. SF 1459370
  • It doesn’t seem to offer an RSS feed for the comments on individual posts. SF 1459391
  • There’s no RSS feed for individual categories. SF 1167982
  • Captcha support is built-in, but seems broken out of the box. (It rejected every attempt to post). SF 1459374

Despite these problems, this looks like a very strong contender. And I was using a beta.

Next up for testing: WordPress.