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Showing posts from 2010

Solaris on Virtualbox

Trying out Solaris on Virtualbox to troubleshoot an issue at work with no luck booting. The VM would hang after the grub prompt. Disabling USB support and sound support did it for me.

Cron Jobs in the Green Data Center

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Yesterday I wrote a script to monitor a UPS (running apcupdsd ) server using Nagios . Today I'm looking at some of the results of the performance data. It seems that the hourly cron jobs on my server actually cause some power usage. I'll have to think over how often it's actually necessary to run those scripts given it's sucking a noticable bit of juice. Check out the graph (produced by PNP for Nagios ) 4 hour Load Percentage of our new APC 2200 @ work

SSH Client Keep Alives

At my new office in the  Shell Building  the main router is a SonicWal l which has a setting to drop idle TCP connections after 15 minutes. This is annoying since I usually have several going at once. I don't have access to the router so I had to work around the issue. The poor man's solution is to run the "top" command on your idle terminals so that packets come through. Not elegant and too manual for me. The rich man's solution is to change the server's keep alive settings (TCPKeepAlive yes). I call this the rich man's solution because it means every one bends over for you. The middle class man's solution is to add some directives to the default SSH client options on your local machine. Here's how: Edit ( as root) /etc/ssh/ssh_config and add the following lines: TCPKeepAlive yes ServerAliveInterval  60 ServerAliveCountMax 5 This means that every 60 seconds your machine will send a keep alive to the server if there is no other acti

Adobe Flash is back for amd64!

Finally the 64 bit edition of Flash is somewhat available again! It's called Flash "Square". I tried it last night on my dual core Atom HTPC running Debian Squeeze. It was amazing. Full screen HD YouTube videos play smooth as butter . I've never seen this with Flash in Linux! Amazing! By the way I still hate Flash but you gotta live with it so... See my edits in the Debian wiki on how to install on a 64 bit platform: http://wiki.debian.org/FlashPlayer#Debian5.0.27Lenny.27and.27Squeeze.27amd64

d.o.t.s in your Gmail address demystified

This is probably not a surpsrise to anyone but me but I still want to share. According to Google: homerjsimpson@gmail.com = hom.er.j.sim.ps.on@gmail.com homerjsimpson@gmail.com = HOMERJSIMPSON@gmail.com homerjsimpson@gmail.com = Homer.J.Simpson@gmail.com Sweet! Now to make it even harder to contact me just e-mail me at e(dot)r(dot)n(dot)e(dot)s(dot)t(dot)o(dot)o(dot)n(dot)g(dot)a(dot)r(dot)o AT gmail(dot)com http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=10313#

1,741 times faster than dial up!

I am checking out the grand new offices for the RAMCloud project at Stanford . The internet here is 1,741 times faster than 56k dial-up! Ironically storage speeds have not grown at the same rate as Internet speeds, that's what RAMCloud hopes to solve (in the data center). This is insane bandwidth. Oh and every PC here gets a public IP! I'm in Internet heaven.

Open Government Data and JasperReports

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Major geek out this evening. I was supposed to go to the gym with Diego but he passed out on the couch from jet lag and I decided to hit the open source reporting space instead (the obvious choice!). I'm evaluating JasperReports , an open source reporting engine. I'm very impressed with the results. Installation: Installation was a breeze - I fired up a Debian 5 VPS on my home server and after downloading the JasperServer package I had my TomCat, MySQL, Java installs all done for me. I had the option to configure each component separately - I opted to have Jasper do all that for me this time. I also decided to give JasperReports-Pro a try under the time trial demo. There's also the completely free open-source edition. Data Source: Once I was able to log into the web interface I had to find some data! I decided to try data.gov . I found some "raw data" on 2008 adoptions per foreign country for United States families. The data came in the form of an .xls f

Dropbox in Debian Squeeze

I decided to give Debian Lenny +1 distribution, Squeeze a try on my work desktop. Things look really good and easy for one of my favorite cloud services, Dropbox . To install (instead of the old manual methods) just enable the non-free repository in your /etc/apt/sources.list : deb http://mirrors.kernel.org/debian/ squeeze main contrib non-free Then you can simply install Dropbox with: apt-get install dropbox

Finally a fix for home, end, page up and page down keys in Mac OS Terminal!

Thanks Mac Improved Blog man: http://macimproved.wordpress.com/2010/01/04/fix-page-updown-home-end-in-terminal/

lighttpd: whitelist some IPs while authenticating the rest

Here's the scenario: you have an office full of people that need access to a certain web app. Some of them probably have insecure passwords and you're too busy to worry about the latest security holes in your web-app. Slow down attackers by allowing your office IP addresses in while denying the open web access until they put in a simple group password. In other words, this post walks you through having lighttpd allow some IP addresses in (and authenticating with your web app) and others to have to authenticate with mod_auth first, then the web app. These instructions were tested on Debian Lenny: First Enable the authentication module: lighttpd-enable-mod auth Create the password file, the format is username:password vim /etc/lighttpd.user Make the password file owned by the webserver user: chown www-data:www-data /etc/lighttpd.user Configure the auth module: vim /etc/lighttpd/conf-enabled/05-auth.conf * Comment out the auth.backend = "plain" line * Co

Pico Projectors

Is the next big (little) thing Pico Projectors? Check out my friend's site http://picoprojector.org/ - he's got pretty comprehensive reviews and news about the miniaturized projectors.

Blackberry Bold 9700 and Mac OS X 10.6.2 Bluetooth Tether for AT&T

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This is a fairly lazy post. I'm assuming you have the devices tethered via Bluetooth - that's fairly common knowledge. What's uncommon is getting it to work. I tried the Blackberry Modem profiles that people cooked up with no luck. What ended up working was this Option N.V device profile. Just follow the screenshots. * Note password is CINGULAR1 The speeds are under a Mbit up and down. Not great but this works. If this isn't working I suggest you tail -f /var/log/system.log while "Use verbose logging" is checked in the PPP properties. Source here (obscure CrackBerry post)

Troubleshooting Cisco/Linksys SPA-942 phones with a syslog Server

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Chances are you're using an Asterisk server on Linux with your SPA-941, SPA-942, or SPA-962 VoIP phones. If you're having an issue, like trouble upgrading firmware it's nice to know what the phone is saying. Simple. Enable remote syslog logging: On your Linux machine, in this case CentOS, enable remote syslog logging in /etc/sysconfig/syslog by adding a -r to the SYSLOGD_OPTIONS line. It will end up looking something like this: SYSLOGD_OPTIONS="-r -m 0" Restart syslog ( /etc/init.d/syslog restart ) and then onto the phone. Enable Logging on the SPA device On your SPA device under (Admin -> System) enter the IP of your syslog server into the boxes and set a debug level (0 is off, 3 is most verbose): Look at your logs: In /var/log/messages you should see some output the phone is putting out. This is an example of a successful firmware upgrade on an SPA-941 Feb 25 13:06:18 10.0.22.114 SPA-941 00:0e:08:23:15:2c -- Requesting upgrade http://10.0.22.

Batch convert Asterisk GSM WAV files to mp3

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I am working on a fun project at work to provide web based visual voice-mail for a ticketing system. I realized Flash audio players are not able to play WAV files so had to work around that. Since users are also using voicemail files in other ways I can't just change the output format from Asterisk. The type of file that I'm working with is identifed with file ms0012.WAV as: msg0012.WAV: RIFF (little-endian) data, WAVE audio, GSM 6.10, mono 8000 Hz First I'll say that I found this post http://www.thiscoolsite.com/?p=73 but like some of the commenters I couldn't get the script to work. The author assumes some other format than Asterisk spits out by default. Lame would complain that Unsupported data format: 0x0031 The Tools Sox: http://sox.sourceforge.net/ Lame: http://lame.sourceforge.net/ So here's what I do: Convert GSM encoded wav to Microsoft PCM sox msg0012.WAV -s msg0012.wav Convert the PCM wav to mp3: lame msg0012.wav msg0012.mp3 And here's a script to

Delete multiple files in Subversion (Linux)

Removed a ton of files from an SVN repo? This will delete all the files that show up with a ! when you do svn status. svn rm $( svn status | sed -e '/^!/!d' -e 's/^!//' ) Thanks to Snippler for the snippet.

Official Google Reader Blog: Follow changes to any website

Official Google Reader Blog: Follow changes to any website

Add sbin to user PATH in Debian

Debian does not add sbin to your path by default. I have no idea why. I know sbin is supposed to be administrative tools that you would only want to run as root, however, there are some useful ones that don't require root, and even if they need root, why hide them from useful tools like auto complete? Apparentely it's not a new disucssion - this Debian mailing list thread dates back to a decade ago! Regardless, I want it in my path - the easiest way that I've found is to modify the top of /etc/profile to remove the if statement that sets path if you're user id 0 (root) or not: Before: if [ "`id -u`" -eq 0 ]; then PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" else PATH="/usr/local/bin:/usr/bin:/bin:/usr/games" fi After: PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin" Save the file, log out and log back in and you're all set. Note that this affects all users on you

Modifying Headers for testing Virtual Hosting

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While working on a website hosted on lighty's virtual hosting environment I realized I wanted a natural way to test the site before pointing the DNS over. If you're sharing one IP for multiple sites then this tip is useful. It uses a Firefox add-on. Get the "Modify Headers" Firefox add-on here. Once installed go to Tools -> Modify Headers Action -> Modify Name -> Host Value -> Domain you want to "spoof" See a list of other headers you can play with here.

Type accents and other Latin American punctuation on your Mac

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I'm helping type some of my grandfather's writing from the 1960s (written on a typewriter, not even worth trying OCR) and I needed some punctuation love on my MacBook, this is what I found. Accents: To write accents on letters, just tap Option (alt) + e and then the letter: á option + e then a é option + e then e í option + e then i ó option + e then o ú option + e then u Enyay (ñ) For ñ, tap Option (alt) + n and then n. Punctuation: ¡ option + 1 ¿ option + shift + ? Read more on Apple's help page.