The Cassandra Blog

So, as I mentioned in an earlier posting, I'm back at University, though this time a US institution so it works a lot differently than my previous experiences in Australia.

Simply put, not only is it different in this country, it is also different in each state, and then it gets even weirder as different institutions handle matters differently.

I may not have mentioned previously what my interest was in returning to University, so I'll describe it here. In simple terms, around January I decided to get back online and visit a few of the GLBTIQ IRC channels I used to be involved with, most of them had dissolved, but I was able to find a few that had some people I knew, and started getting back involved in talking to people, and helping them through issues.... Which lead me to a realization, in Australia, helping someone like that isn't a bad thing, but here in the US there is a cultural issue with trying to help someone through such issues. Simply put, the issue is, if the person decides to follow your advice, and it turns into a problem, then you could be sued. I've always liked helping people, but not only the spectre of problems of that nature caused me worry, there was also the "Am I really giving the best advice I can?". So, I figured, I know, why not get trained to become a Therapist, I get protection from being such from legal hassles, but I also get the training in how best to help these people. So... In California, to practice as a Therapist by oneself, you are required by the California Board of Behavioural Sciences to be licensed as an LCSW. Now, it's possible to become a Therapist via a different board, but that requires a PsyD. After doing some research, I found I could meet the initial requirements for the LCSW in 5 years, if I worked my butt off.

So, this lead me to looking at Uni's, etc. I'm currently a student at De Anza College, a community college, which is handling the General Education requirements for my Bachelors course, which I am currently hoping to obtain via a "transfer" to Palo Alto University.

This is my second quarter now, and summer is a lot more work, as it's a regular 13 week quarter compressed into 6 weeks.

Anyhow, so far I'm enjoying the studies, the course work, while long, is not all that difficult, just time consuming. After the next few weeks are over, I then get a few weeks off, during which time, I'll catch up on all the housework and other stuff I've set aside in the past few months...

Things have been hectic these past few months.

My saltwater tank ran into a bit of an issue, problem with using natural sea water as opposed to mixing my own like I had been in the past. It caused a minor tank crash, I lost all my CUC, and at least one of the corals. It also caused enough damage that the other corals are still recovering.

Here's current tank pictures:-



The Saltwater Tank


The Freshwater Tank


I'm also having a little bit of other fun, as I'm heading back to university in April. It's been a few months of ups and downs, and trying to navigate the broken system for university education in the US. In the area I am in, there is a lot of focus on "General Education", but no interest from anyone in directing that education in a manner that would be good or useful for someones degree. Makes me understand more why US universities have so few graduates, unfortunately. Oh well, perhaps I'll change my mind once I get started in a few weeks, but for now, it's just a headache.

For the past few years, one of the core things at my job (and my side contracts) has been the creation of virtual machines.

I primarily use XenServer from Citrix, as it's fast, efficient, easy to install, less hardware-specific, and a darn sight cheaper than VMWare.

I also do large amount of toolsmithing... and realised, this little script here could save many people a large volume of time, this is the current iteration of the VM configure script I run.

The way I use it is simple:-

• Install a base VM (I normally call this "template")
  
• Configure the VM with any necessary VM guest tools (Xen Guest, VMWare Guest, etc)
  
• Install any necessary packages that should be on all guest VM's (eg. screen, vim, puppet, or whatever)
  
• Copy in this script, and make it executable by root
  
• Power this VM down and convert it to a template, or store as a copyable VM
  
• Create all new machines from the template, and run the script giving the necessary options
  

You will note, this script is currently only directly usable for Debian-based systems (tested with Debian and Ubuntu primarily), or systems that use a Debian-style file system layout. This is because I almost never get asked for RPM-based distro's, and so when I need to install those, they are one-offs in most cases. The script could be fairly easily adjusted to run with those, and if I installed enough of them, I'd modify the script to handle both distro styles.

#!/bin/bash

# configure-vm.sh

# Copyright (c) 2008-2012, Cassandra Brockett

# Authorised for use by all, though I must approve inclusion in a commercial solution.



HOSTNAME=$1

IP=`echo $2 | sed 's/\(.*\)/\U\1/'`



# Change this for the domain of the host!

DOMAIN="example.com"



  

# Check if I am running as root, if not, error and exit

if [ $UID -ne 0 ]

then

	printf "ERROR: This script MUST be run as root!\n\n"

	exit 100

fi



# Check if given the hostname of the host, if not, error and exit.

if [ -z "$HOSTNAME" ]

then

	printf "ERROR: No hostname given!\n\n"

	exit 10

fi



# Check if given the IP Address of the host, if not, error and exit.

if [ -z "$IP" ]

then

      TESTIP=`host oph-slvdns01 | sed 's/.* has address //'`



      if [ -z "TESTIP" ]

      then

              printf "ERROR: No IP address given!\n\n"

              exit 10

      fi



      IP=$TESTIP

fi



NETMASK=`ifconfig eth0 | grep -i "inet addr:" | sed 's/.*Mask://'`

GATEWAY=`route | grep -i "default" | sed 's/default         //' | sed 's/ .*//'`



# Make sure vm is fully updated...

apt-get update

apt-get -y dist-upgrade

apt-get -y dist-upgrade





# Create hostname file

printf "$HOSTNAME\n"							> /etc/hostname



# Create hostname file

printf "$HOSTNAME.$DOMAIN\n"                                            > /etc/mailname



# Create hosts file

printf "127.0.0.1\tlocalhost\n"						> /etc/hosts

printf "127.0.1.1\t$HOSTNAME\n"						>> /etc/hosts

printf "\n"								>> /etc/hosts

printf "# The following lines are desirable for IPv6 capable hosts\n"	>> /etc/hosts

printf "::1     localhost ip6-localhost ip6-loopback\n"			>> /etc/hosts

printf "fe00::0 ip6-localnet\n"						>> /etc/hosts

printf "ff00::0 ip6-mcastprefix\n"					>> /etc/hosts

printf "ff02::1 ip6-allnodes\n"						>> /etc/hosts

printf "ff02::2 ip6-allrouters\n"					>> /etc/hosts



# Create interfaces file

printf "# This file describes the network interfaces available on your system\n"	> /etc/network/interfaces

printf "# and how to activate them. For more information, see interfaces(5).\n"		>> /etc/network/interfaces

printf "\n"										>> /etc/network/interfaces

printf "# The loopback network interface\n"						>> /etc/network/interfaces

printf "auto lo\n"									>> /etc/network/interfaces

printf "iface lo inet loopback\n"							>> /etc/network/interfaces

printf "\n"										>> /etc/network/interfaces



if [ "$IP" = "DHCP" ]

then

	printf "# The primary network interface\n"					>> /etc/network/interfaces

	printf "auto eth0\n"								>> /etc/network/interfaces

	printf "iface eth0 inet dhcp\n"							>> /etc/network/interfaces

else

	printf "# The primary network interface\n"					>> /etc/network/interfaces

	printf "auto eth0\n"								>> /etc/network/interfaces

	printf "iface eth0 inet static\n"						>> /etc/network/interfaces

	printf "\taddress\t\t$IP\n"							>> /etc/network/interfaces

	printf "\tnetmask\t\t$NETMASK\n"						>> /etc/network/interfaces

	printf "\tgateway\t\t$GATEWAY\n"						>> /etc/network/interfaces

fi



# Below here, do anything special you wish to do for each system.

So, needed to export from OpenSCAD so we can cut some stuff on a laser cutter....

God this is a nightmare process, spent a good few hours trying to figure out what's up with it, and finally figured it out. The "proper" method is as follows:-

1) Export from OpenSCAD to a PNG file.
2) Load the PNG file into Inkscape.
3) Have Inkscape run a path trace algorithm on the png file.
4) Spend ages (even a simple file can be five-ten minutes of fiddling) cleaning up the paths.
5) Complain, moan be annoyed as Inkscape's output just isn't straight, and is strangely laid out.


Okay, number 5 is just my step mostly I finally decided that this just wasn't a good method of handling the export, so after a quick google search I discover that the program I used to slice the STL files I generate from OpenSCAD for printing on the RepRap will also export SVG files... and what it does is generate it so each layer is a grouped option in Inkscape... hmmm.... okay, so the new method (which by the way takes about thirty seconds for me now) is:-

1) Export from OpenSCAD to an STL file.
2) Load Slic3r and tell it to export the STL as an SVG file. (Note here, see below)
3) Load the resulting SVG into Inkscape.
4) Delete all layers not needed for the cut.
5) Ungroup the layer, set No Fill and have the Stroke solid with a 1 pixel width.
6) Rejoice as the output looks perfect.... then save the file.

Okay, the only concerns here is that Slic3r needs to have a few settings adjusted to generate nice looking SVG slices, first off, 0 Infill, 1 Perimeter and 0 Solid Layers, not sure if this really makes much difference but it works for me.

Given this I can now generate what appear to be valid SVG files for use with the Laser Cutter.... hope so as the Hubby is going to give them a whirl in a few hours.

So, have been playing with the RepRap, and while it's mostly amusing, I get really tired of it working just fine, then some minor thing goes askew/awry, then have to take have the dang machine apart as fixing that causes or shows up a much larger issue.

So far we've had to disassemble the darn thing once a week... and it's annoying as all hell.

Also, we're stuck with a 190mm (x) by 160mm (y) by 90mm (z) axis maximums, even though the official build area is supposed to be 200x200x100. Have some thoughts on how to fix it, but it basically involves rebuilding the machine... again... and perhaps having another few weeks of random rebuilds to fix the minor issues. At this point I'm not interested in fixing anything on the darn thing unless I can get it to work properly for a week.

Tried to stop by TechShop as the Bay Area RepRap club meets at the SJ location.... seems they can't be bothered with proper sales, I was there for all of about 30 seconds before they where trying to shove me out the door to talk exclusively to my husband... bad move as they've likely lost the pair of us as potential customers. We where going to ask them a few questions and such but they apparently have screwed up process about things, and the fact that (as normal for me) I wasn't wearing closed toed shoes they didn't want to talk to me at all.... or maybe it's the husband/wife pair walk in obviously it's the husband who wants the membership... not the wife who actually has the ability to get there at times the hubby can't.... considering we mostly wanted access to a laser cutter, with what they want for a years membership, I'll just buy a cheap one, or pay the same as two years and get a large one I hate idiot sales critters.