Thursday, February 26, 2009

My new album


Here are the rules:

1 - Go to Wikipedia. Hit “random”
or click
The first random Wikipedia article you get is the name of your band.

2 - Go to Quotations Page and select "random quotations"
or click
The last four or five words of the very last quote on the page is the title of your first album.

3 - Go to Flickr and click on “explore the last seven days”
or click
Third picture, no matter what it is, will be your album cover.

4 - Use Photoshop, GIMP, Inkscape, or similar to put it all together.

5 - Post it to FB with this text in the "caption" or "comment" and TAG the friends you want to join in.

Picture is

Quote (title) is: There are two kinds of light--the glow that illuminates, and the glare that obscures. - James Thurber

Band name is from

And you get:

Friday, February 20, 2009

Hey IASA, check out what your Malaysian Chapter is doing!

Obi and I were wondering what our esteemed IASA chapter is doing in Malaysia (IASA-M), so we decided to visit their website. However their address is not obvious, so google it was.

Suffice to say, I was surprised at what IASA-M meant. Kids these days ... So for the benefit of the sensitive readers, here is the direct link to IASA-M.

Hopefully this would increase their PageRank to avoid further embarrassment.


Tuesday, February 17, 2009

Xen: DomU having exclusive use of an ethernet port

I'm setting up an internet facing server which would have a limited number of services exposed. I'm also testing out the capabilities of Xen. Because the hardware I'm testing on is a 3 year old Dell 1U server with no hardware RAID0, I can't use VMWare ESXi (the free one) which would be a simple click and run.

So Xen it is. Installed CentOS 5.2, with software RAID0 (thank you mdadm!), and ofcourse with the Xen kernel enabled. Installing a new CentOS image was relatively straightforward;
  1. Use virt-install
  2. If you are having problems in setting the ISO image as the source, you can
  3. mount -o loop Centos.DVD.iso /var/www/html/centos/
  4. use http://[localLANIP]/centos as the repository
So back to the issue at hand. The Physical server has two network cards. One is allocated as a trusted LAN card (eth0), and the other card is the untrusted WAN card (eth1). Normally when you install your server, you have access to both ports.

However if you want the Dom0, the Xen physical server which hosts the child Virtual Machines (DomU) to be insulated from the internet, you need eth1 to be invisible to Dom0.

To do this, you will need to mess around abit. Parts of this guide comes from here and here. And you will need a kernel module called pciback. To test that you have pciback in your system, do this:
# modprobe pciback
# lsmod | grep pci
pciback 29389 0
Wonderful, it comes by default with the stock CentOS 5.2 distro. Next you will have to find out which PCI address to look out for.
# lspci |grep Ethernet
00:03.0 Ethernet controller: 3Com Corporation 3c905C
00:10.0 Host bridge: Broadcom I/O Bridge with Gigabit Ethernet
00:10.2 Host bridge: Broadcom I/O Bridge with Gigabit Ethernet
01:03.0 Ethernet controller: Intel Corporation Ethernet Pro 100
The one I was interested in is the 3Com card. So remember 00:03.0 . I tried the kernel comand arguments as described in the URL above, but that didn't work. Fortunately in Linuxland, there is always more than one way of doing things.

First, modify /etc/modprobe.conf manually
# cat modprobe.conf
alias eth0 e100
# 090217 yky Hiding eth1 from Dom0 to be revealed to DomU
#alias eth1 3c59x
options pciback hide=(0000:00:03.0)
Basically pciback "seizes" any PCI devices before the kernel can get to it. Which is why it has to be preloaded early on. Unfortunately pciback is a dynamic module residing in the filesystem, which may not be in the ramdisk when the kernel is loading. So you will need to add it to the ramdisk by running this command.
# mkinitrd -f --preload=pciback /boot/initrd-$(uname -r).img $(uname -r)
# ls -la /boot/initrd*
-rw------- 1 root root 2280203 Feb 17 17:42 initrd-2.6.18-92.el5xen.img

Now you are ready to lose eth1 from Dom0. Reboot. To confirm this to yourself, do this:
# dmesg | grep eth
e100: eth0: e100_probe: addr 0xfcf00000, irq 18, MAC addr 00:90:27:D3:A8:BC
e100: eth0: e100_watchdog: link up, 100Mbps, full-duplex
eth0: no IPv6 routers present
e100: peth0: e100_watchdog: link up, 100Mbps, full-duplex
device peth0 entered promiscuous mode
xenbr0: port 2(peth0) entering learning state
xenbr0: port 2(peth0) entering forwarding state

# dmesg | grep pciback
pciback 0000:00:03.0: seizing device
pciback: vpci: 0000:00:03.0: assign to virtual slot 0

# ls -l /sys/bus/pci/drivers/pciback/
lrwxrwxrwx 1 root root 0 Feb 17 17:52 0000:00:03.0 -> ../../../../devices/pci0000:00/0000:00:03.0

Previously eth1 would appear where eth0 did. Now not so. eth1 has been seized.

So the next step is to make 00:03.0 available to the DomU guest VM. To do so, your Xen config file should look something like this:
# cat /etc/xen/DomU1
name = "DomU1"

memory = 178
bootloader = "/usr/bin/pygrub"
disk = [ "tap:aio:/xen/DomU1/DomU1.img,xvda,w" ]
vif = [ "mac=00:00:ee:24:9a:73,bridge=xenbr0" ]
pci = [ "00:03.0" ]

The vif ... bridge=xenbr0 will provide a virtual NIC to the DomU which can be connected to the trusted LAN.
The pci = [ "00:03.0" ] defines the PCI address which is accessible to the DomU to probe. On a successful bootup, it should detect it as a pure 3Com card as Dom0 used to do.

You can now configure eth1 as per normal. Dont forget to bring up them firewalls!


Saturday, February 14, 2009

The World of Goo ... and it tastes Goooood in Linuxland!

The common problem about running Linux at home is that you get so left out when it comes to games. Ive only just found out about OpenArena and Nexiuz, which satisfies my FPS needs. Im not much of a puzzle fan, but once in a while, a surprising and really interesting game comes along.

The game is called "The World of Goo". It features blobs which you can manipulate into wobbly shapes to build structures; towers, bridges to get the goo blobs from one place to another. It looks like a really souped up Flash game, except that the gameplay is far more complex and enthralling.

Whats better, the developers invested a little bit more to release it on Linux (deb, rpm and tarballs are available.) And it doesn't cost that much, at USD20.
This is what it looks like when you are tasked to build a bridge over a crevase. The links between the goo blobs are strong, but very wobbly. Any chance of latching on to solid walls must be taken advantaged of to build rigidity.
I really liked the Frog level, which was entitled "Not too high, not too low" because as you can see in the background of this screenshot, the "tongue" of the frog has to be suspended by the pink baloons which you manipulate. However if you place too many baloons, the ceiling is laced with spikes which would explode em, dropping your bridge to the bottom which destroys your ladder. Its quite evil.
What Im really impressed about is the art direction of this game. Its very colourful, the UI elements blend extremely well including the blobby cursor. The sound is cute, with a suitable soundtrack. The squeels of the blobs as you pick and place them remind me of Lemmings. Infact the game play is Lemming-like.
2D Boy, the developers have not DRM'ed the game, and offered Chapter 1 as the free demo levels. Ive played it Linux, and the performance was smooth, with no problems full-screen and windowed (as pictured). There is virtually no help in the game, not that its needed, but each level has some sign boards which are crypting and haiku like. Annoying but you just have to click on it.
Its a really good game, and I would recommend it, especially for those who love abit of puzzle solving, mouse dexterity and good clean fun.

Read on for more info via the HeliOS project.


Thursday, February 12, 2009

Random Pictures #1

I spotted a few funny opportunities to snap a few pictures over the past Chinese New Year holidays, and within a span of three days, an Adult theme seemed to emerge.

First off, spotted in Genting Highlands was this poster which highlighted the attractions at their Theme Park. At attraction #10, Gentings is proud to present "Adult Bumper Cars".
Now. I wonder if clothing is optional, or they have private rooms, or there are big exotic dancers. Whatever it is, they'd better practise "Safe Driving."

Then the very innocent game called "Super Mario Galaxy" sports a rather unfortunate camera angle when Mario, that hot blooded italian plumber, captures several cute white fluffy rabbits which talk. The picture doesn't do much justice to the lewdness, because the bunny squirms in a way which is rather disturbing. And look at Mario's face, that pervert!

Good thing its bunnys and not .... cats. Or goats.

To conclude the "Inadvertent Adult theme", around the streets of Wangsa Maju, a suburb north east of KL, there seems to be a demand for "Spring Return" the ultimate male performance enhancing drug. I wonder if it comes with sound effects - "g-doiiiiiingggg!" "bwaaaang!" Or it actually means something more romantic like the return of Spring, the season. I think not.
Im just wondering if the flat for sale is the neighbour who lives under an addict of this drug. Whatever the case, Ditesh's wifey methods would be a great complement to this new enhancement.