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6 May 2009 Website launch nears…
The new website is nearly ready to go live … after some heated design discussions and some rapid revision of modern web standards, I’m pretty excited, it looks great!
27 Apr 2009 CCIT in charity role
ccit will be devoting some engineering time to helping out the Citizen’s Advice Bureau with the management of their computer systems.
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frequently asked questions
This is a small collection of useful information concerning the management of IT systems. More of an aide-memoire than any serious technical questions, but handy even so.
System admin - Windows
Q. How do I get a privileged command prompt with Vista / Windows 7?
A. Type 'cmd' into the search box on the start menu. Hit Ctrl-Shift-Enter, and then confirm the privilege escalation in user account control.
System admin - OS X
Q. How do I use dd to make a .iso file using the Mac OS X Terminal?
A. (from here): 1. put the CD/DVD in the drive. 2. type drutil status to get the location of the drive in your filesystem. 3. Unmount it: diskutil unmountDisk /dev/disk?. 4. Create the .iso with dd: dd if=/dev/disk? of=/path/to/the.iso bs=2048 nb bs=2048 is pretty arbitrary but will likely suffice. 5. Celebrate - you've made the disk image.
System admin - Unix
Q. How do I search through a lot of files to find those containing a certain string?
A. Use grep with options r (recursive search), i (ignore case), I (ignore binary files) and l (list the files with matches, rather than outputting the match)::
grep -rilI 'the search string' *
Q. My SSH terminal keeps timing out and locking up. How do I prevent this from happening?
A. Set a keepalive value on the client. In ssh_config, usually in /etc/ or /etc/ssh/, add the following to keep the connection fresh:
ServerAliveInterval 60
Q. I'm using dd to copy data between disk drives, images, etc. How do I know how it's getting along?
A. On linux and bsd, find the process id and use
kill -SIGUSR1 <pid>
And on Mac OS X, use
kill -SIGINFO <pid>
Web development and Internet
Q. I'm trying to send a HTML, table-based email to a hotmail address and get strange white space between table rows and some images. How do I solve this?
A. Remove the height attribute from the table, and add style="display: block;" to all images in the mail.