The Deliverator – Wannabee

So open minded, my thoughts fell out…

Archive for the 'Blogging' Category

Thoughts on blogging

Did you pass math?

Posted by Deliverator on 6th October 2006

I have been using Akismet for a while to catch comment spam. In general, it works quite well, with an extremely low false positive rate and an equally low false negative rate. I have noticed a few more of late that have managed to sneak through as legitimate. This doesn’t perturb me too much, as I moderate all comments anyways before they are actually posted to the site. Also, once I have labeled the few that sneak through as spam, Akismet usually becomes very good at catching similar ones in the future. Still, I have become loath to spend my time to login and review Akismet’s. In an effort to ensure that reader comments get posted in a timely manner (and that they don’t continuously repost because their comment didn’t go through right away), I decided to install another spam filter plugin in addition to Akismet and to start approving comments through email. I initially played around with a spam plugin called Hashcash, which has an excellent reputation for being an utter brick wall against comment spam. However, I didn’t like its reliance on javascript, as it would require readers of my page who wish to comment to be using a modern, desktop web browser. A small but significant percentage of readers of this site are browsing on HPC devices with antiquated web browsers with flaky javascript support. So, instead I decided to try a plugin called Did You Pass Math?. DYPM simply requires a commenter to answer a grade school level math question when attempting to submit a comment. If they don’t answer the question correctly, the comment is completely rejected. If they answer it correctly, it gets thrown through Akismet and thenceforth into my moderation que, triggering an email to YT to approve the thing. So far, I have not had a single comment suceed in even getting to the secondary Akismet review stage, which may say a lot about the readership of this site. The plugin does appear to be working with the few test comments that I have generated. Let me know if you notice anything wonky….if you can!

Posted in Blogging, General | 2 Comments »

Galleries are Back Up

Posted by Deliverator on 18th July 2006

Ryan noticed that his gallery install was having some issues earlier today. On a hunch, I tried accessing mine and sure enough, my gallery was horribly, horribly broken by the move, as well. I decided I might as well upgrade to 1.5.3 while fixing the other problems, so I went ahead and steeled myself for a couple hours of head scratching and google searching. I quickly tackled a problem with absolute paths being used in one of the config files, rather than a path relative to the webroot or gallery root directories. I then encountered a few permissions problems that were quickly fixed. Finally, I encountered a problem with Gallery not being able to use short names for directories, which more or less broke every image link on the site, as I had always copy pasted the short urls, and gallery could no longer use anything other than hugely long ones. According to the configuration wizard, this was supposedly due to an issue with a .htaccess file or mod_rewrite being enabled in Apache. I would have been trying to figure that one out for hours, but for Theo’s help in eliminating those possibilities and quicky settling on the issue being with a vhosts config file.

I haven’t done much in depth checking, yet, but my gallery now appears to be working at its usual level of disfunction. If you notice any problems with the gallery or other areas of this site, please let me know.

Posted in Blogging, General, Linux, Tech Stuff | No Comments »

It’s Alive! It’s Alive! Frankenputin is Alive! Igor, champagne for everyone!

Posted by Deliverator on 16th July 2006

Silverfir.net is now being hosted on Frankenputin (new server). A few services like the mailing lists are staying on Oasis (old server) until Ryan is able to test the migration path, but the web sites are now all hosted on Frankenputin. Ryan has gotten most of the heavily trafficed sites up and will work on the minor/archived sites as time allows. Frankenputin currently resides alongside Oasis, but will hopefully be moved soon to a new facility at the offices of CascadeLink. Now that the main software changes have been made, it should be a simple matter of a dns change. Ryan uses no-ip for dns, so the changeover should be almost instant. Silverfir will incur another few hours of downtime while we physically move the server and drive arrays, but after that, hopefully Silverfir’s new home on Frankenputin will enable it to achieve uninterrupted service (at least due to the hardware) for a long time to come. Oasis will remain in place as a backup server and will be synced with Frankenputin on a regular basis. Theo has been working on a revision control system for the server which should allow for point-in-time differential backups, which should protect us against any unfortunate software or user induced malfunctions.

Posted in Blogging, General, Tech Stuff | No Comments »

MRAM

Posted by Deliverator on 10th July 2006

It is not very often that one of those “it will be out in 3-5 years” storage technologies actually reaches the market, so I was very interested in seeing that Freescale Semiconductor is now shipping MRAM chips. The chips are a very modest 4mbit capacity, but as they are being manufactured on a very large 180 nm process, capacity will go up as more modern fabs are devoted to manufacturing. So, what is MRAM and why the hell am I excited about it?

MRAM

MRAM is a persistent memory storage technology with no moving parts. In this way it is a bit like flash memory, which is most commonly known to people as the technology behind those little USB thumb drives that you can carry on your keychain, and a bit like your hard drive, which is most commonly known to people when it crashes and eats all your data. Unlike flash, MRAM stores data magnetically, like a hard drive. Unlike a hard drive, it has no moving parts, so it is much more reliable and uses up much less power.

One of the chief problems with flash technology is that it has always lagged behind hard disk technology in terms of storage capacity. The highest capacity hard drives these days are 750 GB. The highest capacity USB flash drive one can readily purchase in a storage is 4 GB. Another problem with flash is that all flash memory can only be written to a certain number of times before a particular memory block goes bad. This can be dealt with somewhat by keeping a lot of spare blocks free and to spread the writes equally over the entire memory using “wear levelling” techniques. Still, the fundamental problem remains that if you frequently write/update data (for example, an OS’s paging file) on a flash based drive, it will die a quick death. Some specialized embedded Linux distros have been developed to minimize writes by mounting themselves read only. One early such distro is Pebble Linux, which sadly is very dated at this point. Rob Flickenger took the Pebble, adapted it for his company’s Linux based WiFi routers, and then re-thought the concept and came up with Pyramid Linux, which is based on the more modern Ubuntu Linux. MRAM could make it possible in the very near future to create reliable embedded devices with full r/w abilities.

The other major benefit of MRAM is that being a chip based technology, it should have very short seek times and be able to handle random i/o patterns, which would cause a hard drive’s r/w heads to thrash back and forth like in a dog watching Wimbeldon. Also, as a chip based technology, it should be far more reliable, due to the lack of moving parts and be virtually impossible to physically damage. In my line of work, I am often meet new clients due to failed hard drives. While I am happy to be able to eat and pay for gadgets as a result, I would frankly rather be doing things other than data recovery and implementing backup solutions. I probably see 2-3 hard drive related clients in an average week and hard drives by far remain the most common physical cause of computer hardware problems. With hard drive technology finding its way into an increasing number of electronic devices like PDAs, MP3 players, cell phones, digital video and still cameras, gps navigation systems, etc. one can only expect hard drive related problems to increase, particularly as the hard drive technology used for micro-drives is quite a bit less robust than their desktop cousins.

MRAM has the potential to offer all the benefits of magnetic hard disk technologies with all the benefits of flash based technology. There is also speculation that MRAM may be fast enough to replace traditional random access memory in a variety of applications, making it the near universal memory techology. MRAM is on the market now. Whether it has a future is anyone’s guess. The major sticking points, imo, will be:

– whether the market will pounce due to the benefits, or will stay with the devil it knows.
– Will fabricators divert capacity from manufacturing know profitable but low margin products and risk trying to manufacture higher capacity modules? MRAM is not very interesting in it current .5 MB per chip capacity. In theory, magnetic technologies can scale to far smaller sizes/greater density that flash based products. This has been demonstrated by the ever increasing capacity of hard disks relative to flash devices. We will have to see if MRAM follow a similar pattern.
– The current cost of the MRAM chips is around $25/chip. I have a hard time imagining that this part is very attractive given its small capacity and high price.

Posted in Blogging, General, Rants and Raves, Tech Stuff | 2 Comments »

Server Yoyo

Posted by Deliverator on 5th July 2006

Ryan brought Oasis’s (old server) data drive over the other night. We struggled to get it recognized on the DL 380’s sole EIDE port (it is pretty much a 100% scsi system, with a EIDE bus only to support the cd-rom). Moving to Plan B, I mounted the disk in an old Dell desktop I had laying around, booted into Linux using Knoppix (version 5 was just released!), mounted the drive, futzed with some permissions issues and then transfered the contents of the drive to Frankenputin (new server) using Rsync. Rsync is a great tool for syncing data over a network, with built in integrity checking and differential transfers. Rsync transfered the data flawlessly, although the transfer took quite a while to complete, as the two systems were connected through a 802.11b link. I handed Ryan back the old server’s hard drive tonight and he has reinstalled it in Oasis, while we arrange to colo the new server with Chris Flugstad’s outfit, Cascade Link. Ryan has been busy setting up Apache, Mysql, etc., so we are pretty much just waiting to get our move-in date from Chris.

Posted in Blogging, General, Linux, Tech Stuff | No Comments »

WordPress 2.03 Upgrade

Posted by Deliverator on 20th June 2006

Upgraded WordPress, the software that runs this blog, to version 2.03 tonight, due to a number of reported security issues with 2.02. As with most wordpress upgrades, upgrading was as simple as uploading the new version files via ftp. Yeah, you are supposed to disable plugins and go through a whole checklist, but when it comes down to it, it is just a matter of overwriting a bunch of files. If you notice any wonky behavior, please post a comment, unless the wonky behavior is that the comment system is broken. Oh, and yes, the colorscheme is as intended. I am colorblind, and it is what looks good to me. Yes, seriously…

Posted in Blogging, General, Rants and Raves | No Comments »

Frankenputin

Posted by Deliverator on 18th June 2006

Silverfir will shortly be making the move to new hardware. To be specific, this hardware:

Frankenputin

The new server’s stats are:

  • Compaq DL 380
  • Dual PIII 933mhz processors
  • Dual redundant, hot swappable power supplies
  • 640 MB ECC memory – will likely be expanded to 4 GB to provide enough overhead for OS virtualization
  • Smart Array 5300 series raid controller with 64 MB cache
  • Three 9 GB SCSI drives in Raid 5 for boot volume, with a fourth drive sitting around doing nothing. Controller supports designating drives as a “hot spare.” In the event of a drive failure, the controller brings the fourth drive in as a replacement for the failed drive.
  • Fourteen 18.2 GB 10k RPM SCSI Ultra 3 drives in external “StorageWorks” enclosure. The 5300 series controller supports a proprietary “advanced data guarding” mode which protects against up to two simultaneous drive failures without data loss. One, possibly two, of the drives appears to have been damaged in transit and the front metal pieces which lock to the server cabinet were bent. I hope I can simply bend them back. All told, the external bay should still have close to 200 GB of very redundant storage.
  • Remote Insight Lights Out Edition II remote management card. Acts kinda like a IP based KVM, giving one local console level remote control abilities. Not only can you use the keyboard and mouse and see what is on the screen, but you can control the computers power state, view the hardware event log even if the server is dead, and even start OS installs using the boards “virtual floppy” and “virtual usb media” features. Just for kicks, I installed Debian “Etch” on the server without ever touching it. A remote management card like this can really make working with a server easier and can save you from a lot of unnecessary trips to the datacenter. The RILOE II card is a much better implementation of the remote admin concept than the 1st generation RILOE card (which was in the server, previously). It is well worth the extra cost.

Aside from the hardware, we are going to try and keep the outward appearance of Silverfir the same. It will still be hosting the same content on the same old domain name. Ryan and I did feel that the server deserves a new name (the current server is named Oasis). I wanted to find a name that made some reference to some important aspects of the new server’s character:

-Big
-Noisy
-Hard to kill

Ryan came up with a slew of military vehicle references, but that didn’t seem quite right. I liked the name Rasputin in reference to the politically bothersome Russian who proved very difficult to kill. Somehow, that name didn’t sit quite right with me, either. I eventually settled on Frankenputin, as part reference to Frankenstein’s Monster, as the server is made up largely of individually assembled spare parts, as part reference to Rasputin and putin is slang for computing. Anyways, we should be transfering the data off Oasis to Frankenputin in the next few days. We might do things the quick and dirty way, so there might be some downtime during the next week.

I would like to note that Nate from local surplus server parts dealer Nautilus, was very helpful in getting me some of the more obscure parts I needed. Their parts were reasonably priced and they were willing to stand behind their product when one of the items turned out to be defective. If you are in the market for some used server gear, check them out.

Also, the ebay seller (of the drive enclosure which met with the shipping accident), still_the_same, is shipping me a new enclosure, as well as two replacement drives. All told, she is eating quite a lot of shipping costs, so I would like to compliment her on her professional handling of this issue. My guess is she is making no money on this transaction as a result, so the least I could do is give her some free advertising. She has a number of servers and server related hardware for sale and seems to be the real deal, folks.

Posted in Blogging, General, Tech Stuff | No Comments »

We are off!

Posted by site admin on 26th April 2006

Ryan and I are on the plane and will be headed to Atlanta, shortly. I am
doing a last minute check of my email (via t-mobile edge) before we take
off. I will be gone till Sunday, but will be checking email and
voicemail. Cya!

Posted in Mobile Blogging | No Comments »

Strong Performance, Poor Results

Posted by Deliverator on 4th March 2006

Since my last update, a lot has happened. Ryan arrived late last night.
Even after a long day of school and many hours stuck in traffic he pulled
out his laptop and got to work updating the autonomous code. Almost
everyone got up extra early this morning and helped out with the testing
the last minute code revisions. It was really nice to see everyone turn
out to be supportive of the few people who could do the coding work. Ryan
managed to get a lot done in a very short time and we are now scoring 8
or 9 of or 10 balls during autonomous, again.

We have been performing very well, individually, but we have for the most
been paired with poor performing partners. In our last match,TRC scored
all of our teams 38 points and both of our teamates were tipped over or
immobile for almost the entire match. Ian managed to play strong defense
against 3 very good offensive bots (including 254, one of the best teams
in the nation) for the entire match, holding them to 58 points.

It is disappointing to have won soo few matches while playing very well.
I haven’t taken a look at or seed ranking for in a while, but my guess is
it has taken quite a nose dive. I hope the seeded teams have been paying
attention, so that we get picked for a strong alliance during the
playoffs.Still, I am very pleased with our performance thus far,
especially given the lack of practice time before coming to the
competition. I am very pleased with the team involvement this year. Many
more students have dug in and made significant contributions to the club,
hopefully learning a thing or two along the way and having fun and making
friends. The TRC may not defend its back to back titles this time around,
but I think we have made a very strong showing and will be even stronger
this next year.

Posted in Mobile Blogging | No Comments »

Arrived

Posted by Deliverator on 2nd March 2006

Made it down to Portland this afternoon. It is 1:30 AM and we are still working hard. Have to get up at 6 tomorrow to uncrate the robot at 7:45 tomorrow. We will be very busy with autonomous programming for much of the day. Here are some brief thoughts on the day:

-Mobile SWN nodes are cool! Had two passengers online almost the whole way to Portland. Students in Larry’s van were using it too, but they had to stay pretty close to get good reception. Might consider a roof mounted antenna in the future.

-Took my annual trip to Powells, although I only got to stay for an hour. Bought some books by Alastair Reynolds and Elizabeth Moon. Kept it to 4 this time around….a personal best.

-Brad Moore’s snores are likely to result in another federal disaster mismanagement probe in which everyone points at someone else

-The Courtyard Marriot is a big step up from the place we stayed at last year, but their wifi is abysmal and only availabe in a very small area of the hotel. They do provide wired jacks in the rooms, but I don’t bring ethernet with my PDA. Will have to investigate some of the portable wifi access points on the market. It couldn’t hurt to get a Socket Low Power Ethernet card, either. I am using my EDGE connection atm, so am very bandwidth limited. Will upload pictures from today when I get a chance.

Posted in CarPuter, General, Mobile Blogging, Titan Robotics Club, Wireless | No Comments »