Posts

cfengine is cool. I dug it. The tutorial was introductory and I was pretty sold on the concepts. If you already know about cfengine there is nothing useful for you in this post. Cheap summary: a host is classified into a number of groups. Lots of classifications are automatic; there’s a linux group (any machine running linux), there’s a 129_120_10 group (any host on the 129.120.10 subnet), there’s a Hr02 group (any host running cfengine between the hours of 2 AM and 3 AM), etc. Why would you want that last? Maybe you only want to do some checks during that hour. Yes, this is yet another way to schedule periodic jobs in a manner that future sysadmins will be unable to find… but I digress. ...

Our VoIP/Asterisk tutorial is going much more quickly than the presenter expected. This is not unusual for first-time presenters. Asterisk is pretty interesting, but shows signs of being an open source project. Hm — OK, some sample configuration file stuff: exten => s,73,Playback(thank-you-for-calling) exten => s,74,GotoIfTime(6:01-18:00|mon-sun|*|*?s,76) exten => s,75,Goto(s,78) exten => s,76,Playback(have-a-great-day-goodbye) In theory, the template is something like exten => ,,(), but it’s been brutally extended into something that looks alarmingly like BASIC. See the line numbers masquerading as priorities? It looks like it was originally just a simple method of specifying extensions, but grew like kudzu. Soon there’ll be m4 macros for building these scripts which masquerade as configuration files.

Speaking of which, the squidguard blacklists might make really good input for MT-Blacklist. Remember this and try it.

My Monday LISA tutorial was on system log aggregation, analysis, and statistics. mjr taught it, and he’s as good a public speaker as ever. Also the topic was pretty damned fascinating. I’ll be dumping a pile of links into del.icio.us sometime soonish now. Highlights, some of which are significant and some of which are just cool: You can set up an invisible loghost. What you do is you specify a non-existent host as the loghost on all your DMZ servers. You’re gonna need to manually stuff an entry into the arp table so that your DMZ servers will blithely send syslog packets off into thin air. Then you hook the real loghost up to the DMZ with no IP address in promiscuous mode. Run tcpdump on it to capture all the packets, and write some cheap perl to strip syslog payloads out of the captured packets. ...

I kinda think I haven’t found the heart of Atlanta yet. I took MARTA up to the Buckhead station, and found a wasteland of shopping malls, alleviated only by a Borders with a stunningly friendly woman behind the counter. Midtown was nicer this morning — the Flying Biscuit is a short walk from the train station, and they do an awesome breakfast. Even if they only have turkey bacon. So maybe Midtown is the right place to be, but there weren’t all that many pedestrians. Hard to figure. ...

What, then, are the fair expectations? How do I judge the next four years? Things I do not expect of Bush: Peace in Iraq. Not because I think he’s incapable of it, but because I think it’s an incredibly difficult problem. I wouldn’t have expected Kerry to make Iraq work either. Things I am willing to judge him on: North Korea. He needs to make progress. I define that as North Korea reducing the number of nuclear weapons on hand without actually using them. He said he could do this with his approach, and he needs to follow through. ...

There is some desire for a Jon Udell-esque library bookmarklet (original) for Harvard’s Hollis Catalog (original). A little bit of research, and there you go. It’s not perfect, since Hollis doesn’t seem to use ISBNs as the primary index, but the first book listed on the results page will be the book you’re looking for if it’s in the catalog.

My friend Rob MacDougall has a nifty new blog, which I cannot recommend strongly enough if you are interested in the history of technology. Share and enjoy.

My pal Jamie’s doing a music exchange — burn a CD with your favorite songs of all time on it, send it to everyone on the list, you know the drill. In one of those fleeting moments of personal revelation I sometimes indulge in, here’s mine. (Yeah, that’s a pretty weak excuse for personal revelation.)

Ashcroft has resigned (original). That’s good.