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John Kawakami's blog
It's one thing to upgrade software. It's an entirely different thing to migrate to new software. If you have a whole system of software, integrated in to a mega-app, it's even more difficult.
This script uses ImageMagick and AVConc (ffmpeg) to convert images uploaded by a low-end DLINK internet camera to an FTP server.
I had a couple of these, and lost the power adapters. (OK, someone else lost them, but whatever.) As always, the voltage and current matter, and these guys use 5V 1.2A or 2A.
I got an Aironet 1200 and didn't have the serial cable, so I tried to use IPSU to find the IP address. I ran it in a VM, bridged the ethernet interface, and it failed.
(argh, forgot to back up my postfix work. i have to start fresh, so this is an opportunity to document work.)
# first get a superuser shell with sudo sudo -s apt-get install mailutils apt-get install postfix apt-get install mailman apt-get install spamassassin apt-get install courier-imap apt-get install courier-imap-ssl apt-get install courier-pop apt-get install courier-pop-ssl # unfortunately, we need to install apache2 because we're going to install # the roundcube mail client apt-get install apache2 apt-get install roundcube
There's a zillion ways to do it, and editing $PATH is probably the best, but I didn't want to do that, so I did this:
for i in ` ls /usr/local/java/jdk1.7.0_21/bin/ ` ; do echo $i ; ln -sf /usr/local/java/jdk1.7.0_21/bin/$i $i ; done
That symlinks all the stuff in bin into /usr/local/bin, which is already in the $PATH.
This is a one-line trick to serve images from a password-protected webcam to the world.
curl -i http://admin:@192.168.111.150/MJ... | nc -lCt localhost 10203
My webcam doesn't have a password, but it could. What this does is use curl to get the stream, and then use nc to serve it to a client.
We have this old Terastation NAS, and it's been solid, but I just figured out that it has support for an external USB disk, and it's easy to set up to backup to the external USB disk. Right now, we're using around 1TB of the array, and it's being backed up to the external disk once a day. The backup is done with Rsync, and it takes around 10 minutes.
I was checking out cloud services a year ago, and pricing them out. The general rule of thumb seemed to be that the up-front costs were lower, but the cost over time was higher. The ongoing costs generally work out to around $60 to $500 per application per user per year.
A typical situation is buying 25 Exchange mailboxes for $5 per month. That's $1,800 per year. That's cheaper than buying a server and Exchange, but not necessarily if you factor in other services running on your hardware.
I was reading the code at iworkfortheinternet.org and learned how to do this "scrolling forever wall" effect. It's clever.
We recently had a rash of spam sending due to someone finding, guessing, or leaking a user's password. Sometimes, it just requires that, not some security breach. Well, we didn't catch it and stop it in time, and now we're suffering some deliverability problems ranging from slowdowns to outright blocking by some servers.
I spent way too much time tonight putting together a sign-in sheet website, called, generically enough Sign-in Sheet.
Under US labor rules, some computer programmers are exempt from overtime laws. There is considerable misunderstanding about this law. I'm not an expert, or even novice, about this law, but am compiling this page as a resource for study and to increase understanding. Corrections to johnk-at-riceball-dot-com are appreciated. If you would like to network and get on a mailing list about this issue, please write to that address as well.
I've re-reading a post I found on Hacker News A simple job queue with Grand Central Dispatch.
I just lost my bag, and in that bag was a sheet with all my slightly obfuscated passwords and usernames and website urls. My trick was to make the information incomplete, so that it's hard to use.