Oh, and Get Me the Machine that goes *PING*

So… it’s been awhile. Partly because I’m lazy, and partly because I’ve been busy at work and by the time I get home, I don’t have much playtime. So what’s new in the world?

Been playing with APRS, the Automatic Position Reporting System (Some links: here, here and here). It’s basically a packet radio system, but instead of normal packet radio which is point-to-point, this is more of a broadcast type system. Packets can be destined for a specific radio, so you can send messages from one system to another, or they can be broadcast for all (all amateurs, that is, not really for the general public and therefore not “broadcasting” in the FCC’s eyes). Since I don’t have a TNC (Terminal Node Controller, basically a modem that connects to a radio) to receive APRS packets in my area, I have it setup with an internet link (the last link above is to APRS-IS, the APRS internet service, which links digipeaters over the internet) on my laptop and at work, the latter runs pretty much constantly now as W2SRH-1. Oh, and just for completeness, a digipeater is for digital packets what a repeater is for analog voice – basically, it takes the packet you send, and re-sends it for all to hear. This way, if you’re running a very low-power radio in your vehicle, your packets still have a chance of getting over a large area if a digipeater picks them up and rebroadcasts them. Now why would you run a packet system in a car? Because you can hook a GPS receiver up to it, and as you move about the planet the little TNC and associated systems will send out your coordinates as a packet, which is picked up by these digipeaters and I-Gates (internet gateways), and someone else with APRS will see a little vehicle icon move across their screen as you travel. Pretty neat! I can watch as people who live in my area, or around the world since I read an unfiltered feed at work (ie, the packets I get are not limited to a specific area), move from one point to another. While that may not sound too interesting to everyone, it is kinda neat to see, and has other uses as well. For search-and-rescue work, an area can be setup where the operation will take place, and if everyone is carrying APRS transmitters then someone can monitor their progress and see what areas they’ve covered. Or in the case of an emergency, someone can pinpoint the location on the map, and others can see it. You could even use it to mark off an event of some sort, or something that others might find important: an accident location on a highway that should be avoided (or where help is needed), or the current and predicted location of a hurricane (which I saw just yesterday). While using this system with a radio is how it was originally intended, it’s still neat to be able to use it with an internet connection.

What else is new lately… we got a new machine at work, which is supposed to hold all the data that people want to keep on spinning platters but not backed up. 15 SATA drives, 200GB each, 3U enclosure. Only one problem: No floppy or CD-ROM drives. No problem, we’ll install Fedora with a USB key! Bought two keys, threw a boot disk on one of them, plugged it in, and… oh, another problem, the damned motherboard doesn’t boot from a USB device. Great. Oh, wanna go three for three? Okay, Fedora doesn’t have drivers for the motherboard’s SATA ports. Hell, RedHat in its entirety, as well as the Linux kernel, doesn’t support them – the company that sold it to us compiled a patch from who-knows-where into the kernel to get it to work. Well this just makes things interesting, doesn’t it? One good thing lately, we got rid of 10 of the old Sun Ultra5 workstations, and there’s only two of them left in the building. Those two will be leaving soon, like as soon as I get my hands on them (one’s in a pile in the server room, and one’s in a pile on someone’s desk). We should have enough computers from the decommissioned Beowulf cluster to replace a couple of the Ultra1 workstations too, and it’ll be good to get rid of them as well. That will still leave us with a few Suns in the building, not as many as when I started but getting close to a manageable number since the one machine that is serving their filesystems is no longer under hardware contract, and starting to show its age.

Along those lines, we also have to move faster on deploying LDAP to replace NIS, since our NIS server is getting overloaded (same Sun that serves ‘/’ to the other Suns). At least I’m guessing that’s what is happening, all I know is that every now and then I get error messages from various machines in the building that they can’t contact Newton for NIS information, but when I login to them things are working fine. NIS isn’t really well equipped for this kind of setup anyway, while LDAP is a bit more robust. I tested some LDAP server stuff today, including replication (where one or more ‘slave’ servers get their information from the LDAP master; the slaves are read-only, the master allows writes also) and auto-failover, and it all worked wonderfully. I setup a client machine to listen to the master and slave, logged in, did some things, killed the master and tried logging in again… and it worked just as fast as when the master was up, only it was talking to the slave now. Tried a write operation, and it failed with “Unable to process request”, quite a fine answer when I try writing to a read-only database. Brought the master back up, tried it again… and it tried to write to the slave, got an error, and bumped right over to the master where it worked fine. Perfect! End result is that I can setup a few slaves, and if the master gets overloaded or goes down, the slaves will continue to serve data, but nobody can change their password (nor can any new accounts be created) until the master returns. Sounds good to me!

Stephanie’s graduation is in a couple weeks, that should be fun. At least one of us graduated from college, and she’s now got more letters after her name than I will unless I get some certifications (but she’ll always have more degrees, I don’t think I’ll ever be going back to school). Before that, however, is … RUSH, Live at the PNC Bank Arts Center in Holmdel, New Jersey … ahh, this should be good. I have heard a couple songs from their latest album, it’s a tribute album with all cover songs from bands that inspired Rush (Geddy Lee singing “…sometimes I wonder what I’m a-gonna do, ’cause there ain’t no cure for the summertime blues…”).

Okay, on that note, I just went and looked up the tabs to Broon’s Bane again, and wish I had a room where I could practice and not wake anyone up. ‘Cause now I want to try to play it again. Like I wouldn’t get frustrated since I haven’t touched either my 6-string or my 12-string in ages, but I still want to play. Grr. Off to bed with me.

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