Saturday, January 31, 2009

FreeBSD and Journaled UFS

Since I have been in an experimental mood lately, I convinced myself to redo the /home partition on my FreeBSD machine to enable journaling. It went pretty smoothly, though since the disk was fully partitioned, it did mean doing a dump and a restore. Fortunately, though /home is relatively large, it doesn't have much stuff in it, so a dump of it fit in the free space on /usr (if this hadn't been the case, I would have just used an external disk over USB). So here's what I did:

1. Boot into single user mode.

2. fsck -p && mount -a

3. umount /home

4. dump 0af /usr/home.dump /home

Now, at this point we're actually going to destroy the existing /home partition, so make sure the dump worked correctly first. In this case, my home partition was on /dev/ad0p5.

5. gjournal load

6. gjournal label -f /dev/ad0p5

I didn't bother specifying a -s argument, so the default journal size of 1 GB will be in effect.

7. newfs -J -L home /dev/ad0p5.journal

8. At this point, /dev/ufs/home should reappear. Edit /etc/fstab and find the line that mounts /home and change 'rw' to 'rw,async' since with journaling enabled we'll be using an asynchronous mount.

9. mount /home . Now type 'mount' and make sure that both 'asynchronous' and 'journal' show up in the list of mount options for /home.

10. cd /home && restore -rf /usr/home/dump

11. Edit /boot/loader.conf and add a line that says geom_journal_load="YES"

12. reboot.

So why bother? Because now /home will not need to have an fsck performed on it ever again.

Monday, January 26, 2009

The DTV transition monkey wrench

The Senate has passed the 6/12 DTV delay bill.

Which means nothing.


Because the delay is optional. That is, the broadcasters can decide to switch on 2/17 if they want to.

You get two guesses how all the TV stations are going to decide, and the first guess doesn't count.

No, this is all about deflecting blame. With a little over two weeks to go in the transition, there are far too many plans in place. There's far too much momentum around the 2/17 date for it to change at such a late date. But if the transition goes poorly, then all of the politicians can tell everyone that it's not their fault - that they gave permission for the delay but that those naughty broadcasters screwed everybody.

Just pull the band-aid off, already.

EchoLink and the Spirit of Amateur Radio.

EchoLink is an interesting new system that allows amateur radio operators to access radio systems (and in particular, repeaters) over the Internet. It's a lot like The Internet Repeater Linking Project, except that EchoLink is not limited to repeater station membership. On EchoLink, individual hams can be nodes and connect with repeaters around the world. The only requirement is to prove to the system managers that you are a licensed amateur radio operator. Fortunately, at least for US hams, proof of holding a Logbook Of The World signing key is sufficient. If you don't have one of those, then other means can be used to validate your license.

So far, so good. EchoLink software is available for Windows, but additionally, a program called EchoMac has been made available for MacOS X users to use.

EchoMac inspired me to perhaps give a thought to writing an EchoLink client iPhone app. Since EchoMac is open source, I should be able to use it to figure out the protocol. But I shouldn't have to resort to that. It's probably easier to simply implement the protocol from its documentation - something I've done a few times before.

There's no mention on the EchoLink site of any protocol documentation. Now, since your connection to the EchoLink servers requires callsign/password authentication, there's no particular Security by Obscurity going on here. That means that there should be no problem with sharing the protocol spec.

So I sent an inquiry in to the EchoLink folks. Here's their reply:

Thanks for writing.

There isn't any good developer documentation available, since the EchoLink system itself was not envisioned as a developer's platform, and we don't encourage development of clients for other platforms.

Really? These are Amateur Radio operators telling folks that they don't encourage development of alternative client software. Do they have any grasp of the history of amateur radio? Have they actually read §97.1(c)?

I still think I'm going to give it a try, since I'm still waiting for sufficient budget to return to the DATV arena and want something to do in the meantime, but I just thought it unbelievably astonishing that that kind of attitude could exist within this hobby.

Sunday, January 18, 2009

DTV transition marches on

On 1/15, a second US TV market joined Wilmington, NC in the post-DTV transition era.

Because of the mating preferences of an endangered Hawaiian bird, the broadcasters in Hawaii have all decided to transition on January 15th instead of February 17th.

Meanwhile, President-elect Obama has called for a delay in the DTV transition. But with 30 days to go, there's just too much momentum to make a change at this point. Beter to just rip the band-aid off.

Friday, January 16, 2009

Tech wish list

Things I'd like to see:

1. Silverlight for Wii. This is sort of a 'hold your nose and deal' wish item. Silverlight forms the underpinnings of Netflix Instant Watching functionality, so any browser where Silverlight is available should support WatchNow. That would be nice.

2. The Roku box to grow a browser. Clearly the box has enough horsepower for one. The UI might be painful, but to be fair, the UI on the Wii Internet Channel is pretty bad too. Ouija board navigation is painfully slow, but if you can make do with it to enter a WPA pass-phrase, you can use it to enter URLs. Ironically, this points out a trend towards the resurgence of WebTV, which it turns out was simply a product released before its time. With the introduction of HD TVs, the TV finally now has sufficient resolution to show a web page properly, and with modern broadband connections there now is enough bandwidth to properly stream video to the TV. There's simply no reason for the Roku box developers to add "modules" for other content providers to the Roku box. All they have to do is give it a browser with enough plugins (flash and Silverlight would probably do) and have done with it.

3. An Apple desktop multi-touch trackpad. I've talked about this in the past, but now with increased stridency. Apple should take the nice glass skating rink they've put on the new Macbook Pros and put it into a small aluminum case designed to attach to the side (either side, of course) of the Apple desktop keyboard. For extra credit, they should figure out how to make a bluetooth version of the same thing to go along with the bluetooth keyboard.

4. Blu-ray support for the mac. I actually don't envision buying a Blu-ray player or Blu-ray pre-recorded media. But support for burning recordable Blu-ray disks would mean being able to back up all of my home directory - including all my movies, music, etc in iTunes - on a single disk.

Thursday, January 15, 2009

Journalistic stupidity

I read this story today. A plane made an emergency landing in the Hudson River after the pilot reported over the radio having run into a flock of birds.

Some tidbits from the version of the story on the above web page really need to be lambasted a bit. To wit:

A spokeswoman for the Department of Homeland Security in Washington said there were no indications that this incident was a result of a terrorist attack.

Really? This wasn't a special squadron of Al Queda trained pigeons? Oops. I shouldn't have said anything. Now I've given them the idea. Sheesh. We'll be hearing that the next earthquake to hit Alameda County wasn't caused by terrorism at this rate.

Doug Parker, chairman and CEO of US Airways, said it was too soon to speculate on what caused the incident.

Hmm. I think you're wrong, Doug, I think it isn't too early to speculate that the impact of the birds your own pilot talked about on the radio just might have had something to do with it. Maybe he's holding out for reports on the Al Queda pigeon roosting program.

Wednesday, January 14, 2009

iPhone supports alternate CA root certs!

I happened to stumble across this earlier this evening. The iPhone now supports adding additional SSL CA root certificates. Here's the flow for adding one. You can follow along if you like. You probably don't have any particular incentive to add the KFU CA root certificate (unless you are a user at KFU), but there's no particular harm. Surf to on your phone and....

Since the server's cert is signed by an unknown CA, that's not unexpected. As part of the bootstrap, you need to blindly accept the server key once.

Once you get the actual content of the page, follow the instructions and tap the "click me" link. You'll be transported into the Settings application and you'll see this:

Tap on "install" and you'll get a scary looking warning:

Don't worry, this is to be expected. Installing SSL CA root certificates is an extraordinary event and should not be taken lightly.

Tap install and you'll get:

Tap the "Done" button in the upper right corner to return to the web page where you were.

You can go into the Settings application anytime you like and find the "profile" and delete it. It's under the "General" menu item.

Wednesday, January 7, 2009

No test this week.

Well, I promised I'd be up on the mountain this weekend, but it won't happen. I don't have a 28 volt power supply for the 33cm amp yet, which means I haven't tested the 33 cm amp, and getting that done by this weekend is unlikely at best.

At this point, I think scheduling a 33 cm test before I've actually transmitted with the amp is pretty blue-sky. I'll keep everybody posted, but I will probably be able to order the power supply with my next paycheck.

Thursday, January 1, 2009

T-47 days and counting

The digital transition at 11:59 PM 2/17 is in just a touch over 47 days.

It takes about 30 days to get your $40 DTV converter coupon.

I'd place your order right now if you don't want to be SOL when they switch them all off.

So, when is the new year, anyway?

Everybody wants to celebrate the instant that the new year arrives, which makes New Year's Day unique in the annals of holidays.

The problem has always been that the North American TV industry operates entirely on Eastern time. We West-coast denizens always get the celebration tape-delayed. But even folks who live in Eastern time aren't going to get a good cue from the TV, since the digital production chain introduces all sorts of delays, not all of which can be compensated for.

The conversion to digital TV broadcasting makes things even worse, because the decoders introduce their own delays, and the magnitude of the delay depends on the decoder, so they can't be compensated for by the broadcaster (this is even assuming that the audio and video maintains the synchronization intended by the broadcaster).

We watched Anderson Cooper on CNN-HD over DirecTV this evening. The ball drop was a full 15 seconds late as I measured it. It's entirely possible that CNN might have been on a (censorship) delay loop for the event, but it's clear that TV is no longer useful for time synchronized events anymore.

And the phone isn't much better. We have Vonage, and if you tune in to WWV on the radio and compare that to calling up WWV on the phone, there's a distinct latency delta between the two.

Never mind the fact that at 0000 UTC there was a leap second this year, so everybody who's been out of the loop on that one will be a second off. At the moment, the NTP server at is a second off, so apparently they didn't get the memo.