How to mount vdi file to Linux!?

First install QEMU on Ubuntu: 

sudo apt-get install qemu

Then run these: 

sudo modprobe nbd 

         // create net disks

sudo qemu-nbd -c /dev/nbd0 /media/ 
         // locate the vdi as a net disk

sudo mount /dev/nbd0 /home/

         // mount the net disk to directory

Check the NIC Number

type in "net config rdr" on the cmd.

VirtualBox - How to forward connections to guest SSH server!!

To set the rule:
VBoxManage modifyvm "VM name" --natpf1 "guestssh,tcp,,2222,,22

ps. TCP is replcable by UDP

To remove the rule:
VBoxManage modifyvm "VM name" --natpf1 delete "guestssh"

ps. VM must be shutdown while setting.

Code Complete: My notes for Chapter 2

Below are the key points listed in the book, I rewrite them a bit using my words. (Hope it does not violate any rules. :) )

1. Using metaphors requires heuristic thinking, not algorithmic.

2. It is actually about analogism to the activities you are familiar with.

3. A programmer should own multi-tools as a toolbox, then use the tools according to the different jobs.

Code Complete: My notes for Chapter 1

Below are the key points listed in the book, I rewrite them a bit using my words. (Hope it does not violate any rules. :) )

1. The most important event in software development is "Software construction".

2. The construction includes design, coding, debugging, and developer testing.

3. The "KNOW HOW" of construction decides how good a programmer you are.

MRTG in FreeBSD

I've searched online for a long time.... but today I found it is not that complicated to run MRTG on a FreeBSD server.

People recommended that installing net-snmpd first before MRTG. Somehow, since I have a FreeBSD 7.2, it has bsnmpd already.

So, all we have to do is to activate bsnmpd by adding the line, [ bsnmpd_enable="YES" ] in /etc/rc.conf .

Then, as usual, cd to /usr/ports/net-mgmt/mrtg to complete the installation.

After installing, do cfgmaker to configure everything as following.

In CLI:

cfgmaker --global 'WorkDir: /usr/local/www/apache22/data/mrtg'  --global 'Options[_]: growright, bits'  --global 'WithPeak[_]: wmy' public@localhost  >  /usr/local/etc/mrtg/mrtg.cfg

Next, the index:

indexmaker  --title 'MRTG'  --addhead=''  --output /usr/local/www/apache22/data/mrtg/index.html  --columns=1  --nolegend  /usr/local/etc/mrtg/mrtg.cfg

Last, run mrtg for about three times till no error messages.

mrtg /usr/local/etc/mrtg/mrtg.cfg

Add mrtg to crontab! (per 5 min)

*/5 * * * * /usr/local/bin/mrtg /usr/local/etc/mrtg/mrtg.cfg

eclipse on ubuntu

Once the JVM is installed...., we can start to use eclipse as our IDE.

0. download eclipse

1. change owned by root on eclipse directory
sudo chown -R root:root /directory of eclipse

2. make eclipse executable (jump to the directory locates eclipse)
sudo chmod +x eclipse

3. eclipse executable
sudo touch /directory of eclipse
sudo chmod 755 /directory of eclipse
sudo vi /directory of eclipse

4. before the 1st run:
eclipse -clean