It is always better to have MySQL Data Directory store in a specific partition/drive. It will help on performance and better management and scalability. You change change the data store directory in Linux by editing /etc/my.cnf file.

Edit /etc/my.cnf file

# vi /etc/my.cnf

Change the data directory structure

datadir=/db/mysql
socket=/db/mysql/mysql.sock

After the file has been updated, restart MySQL service.

$ wget -q -O - http://ipchicken.com |  grep -o -E '(^|[[:space:]])[0-9]*\.[0-9]*\.[0-9]*\.[0-9]*([[:space:]]|$)'
# By default, FreeBSD doesn't have wget, you can use fetch instead
$ fetch -q -o - http://www.ipchicken.com | grep -o -E '(^|[[:space:]])[0-9]*\.[0-9]*\.[0-9]*\.[0-9]*([[:space:]]|$)'

You need port 80 external/WAN access to perform the task.

But if you lock your Linux desktop, the screen will goes blank and you can’t monitor what is projected on your screen. There is a way to do it with screen saver lock, where you can lock your Linux desktop and at the same time to display when application is running on your monitoring screen.

Lock Your Machine with xlock

First, install xlock in your Linux desktop

shell> sudo apt-get install xlock

After xlock has been install, create a file name lockscreen, chmod to 777 and paste the line below in the file

# /usr/bin/xlock -mode image -geometry 0x0 -timeout 1
shell> vi lockscreen
shell> chmod 755 lockscreen

xlock is screen saver lock, but it can disable the screen saver screen by setting display with “-geometry 0x0”.

You can also bind your keyboard short cut key to launch the lockscreen script through System > Preferences > Keyboard Shortcuts.

To check Linux distro on your server

shell> cat /etc/issue

To check Linux Version and distro on your server

shell> cat /etc/*-release

For example I am hosting multiple web applications, the development might have several pg_connect command to connect database, in the event I am migrating database to other IP address, it might be hard for them to dig the file and replace the IP Address with new IP Addresses.

In Linux/Unix, you can search through the directories, looking for the files and replace it with the new IP address. Here is the sample.

shell> find /path/to/dir/* -type f -exec sed -i .backup20100714 -e "s/host=x.x.x.x/host=y.y.y.y/g" {} \\;

The command above will search for files in the directory.
find -type f mean look for File only.
find -exec is to execute something from returned results.
sed -i means backup the files, in case you would like to restore later.
sed -e “s/host=x.x.x.x/host=y.y.y.y/g” is to replace x.x.x.x to y.y.y.y

You have backup files name filename.php.backup20100714, now what you need to do is move the files in a backup directory.

shell> find /path/to/dir/* -name "*.backup20100714" -exec mv {} /your/backup/dir/ \\;

You might want to explore on find command, it can do a lot of cool stuffs.

For example I have a file name wireless.pcap, last update or created was in year 2009. I can change the last modify time by the touch command touch -t yyyymmddhhmm filename

shell> touch -t 201007101540 wireless.pcap

This will change the file last updated date and time to 10th July 2010 15:40pm.

In Linux, using “useradd” is pretty common for creating new user access. You can also use “useradd” in FreeBSD, but not directly invoke “useradd” command. Below is the sample of creating new user in FreeBSD with “useradd”.

shell> pw useradd cheryl -c 'Cheryl Windows Admin' -d /home/cheryl -s /usr/local/bin/bash

New user account is created, but don’t forgot to set password for the account

shell> passwd cheryl

You can run other command like “userdel”, “usermod”, “usershow”, “groupadd”, “groupdel”, “groupmod”, “lock”, “unlock” on FreeBSD by using the “pw” command.

Create a sample file file random name ended with *.sample. Example

touch apple.sample.cfg
touch microsoft.sample.cfg
touch php.sample.cfg
touch config.sample.cfg
touch apache.sample.cfg
touch mysql.sample.cfg
touch pgsql.sample.cfg
touch cacti.sample.cfg
touch wordpress.sample.cfg
touch jessicaalba.sample.cfg

Now you have all the sample configuration, you are going to use them. Are you going to copy one by another and change the same with .cfg prefix? We can do it, in a better and faster way.

Make a new directory to store all the sample file

mkdir sample
cp *.sample.cfg sample/

After that, go to sample directory and copy the files to a location

cd sample 
for d  in `ls *.sample.cfg`; do cp $d `echo $d | sed s/sample.cfg/cfg`; done

That one simple line will easily save you 1-2 minutes.

If you are still new to FreeBSD, here is the step by step installation. For your information, FreeBSD clean installation(developer package) only took 10-15mins(depend on how powerfull is your server/laptop).

First of all, if you have fast/speedy internet connection, grab FreeBSD ISO online from FreeBSD website, it only take you few hours to download with a stable 512kbps internet speed. After you have downloaded FreeBSD ISO DISK1, burn it into a cd.. yes, of course cd, other than CD i can’t any other easier way Beside that, make the FreeBSD installation CD bootable ok?

After you boot up with the CD(I won’t cover how to boot up the CD, kind of silly/stupid), immediately you will see the installation menu as figure shown below;

Select Begin Custom installation(for experts), yes are you expert, because you guide by an expert

Next, let partition your hard disk before the installation, select Partition!

OK, dun be panic see-ing the black and white with text, first, you need to create a “SWAP” partition, how to create a partition? Is an easy job, select the drive and press “C” and it will prompt up a screen as shown below;

Usually SWAP took up (your total RAM) X 2, let said you have total 512MB of RAM in your system, X2 is 1GB. Key in 1G partition and press enter. It’s not done yet, next create a partion again and leave the rest for the space for filesystem. Before you quit, remmeber set the new filesystem partition/boot drive as Bootable. Just select the drive and press “s” and “q” to quit/finished partition. It will look similar like below;

Set it as a standard boot manager

Next, select Label section now to lable your partitioned disks. First is your swap, select the partition with 1GB space and press “C”, Select SWAP – A swap partition from the menu as figure shown below;

and now, select another partition and press “C”, this partition will be a FS – A File System;

set the partition mount point as “/”, figure shown below. It will be the bootable drive for FreeBSD installation.

“Q” to quit partition labeling. Next, select a distributions for your installation. I recommend a light distri, so just select Developer distri. (others distribution packages might need 2nd or 3rd FreeBSD cds)

Next is select commit to start your FreeBSD installtion, and don’t panic when you see….

this

That’s mean installation is about to start….

Figure above shown installation just stated and in process, leave it do the job for about 5-10mins.

Installation DONE! and would you like to configure others stuff? ok.. let me guide you setup simple networking in a LAN.

Select Networking from the configuration menu..

Setup a network with a network Interface card.

configure your gateway, name server and etc..

and yaa.. bring up the network..

and now Exit installation and reboot your machine.. FreeBSD installation DONE!

For more information, check out FreeBSD very usefull and informative manual/handbook here

What to do next? I will blog about it next FreeBSD article!