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How To add Extra Repositories in Ubuntu Linux

A software repository is a storage location from which software packages may be retrieved and installed on a computer.

It's very easy to add extra repositories in Ubuntu Linux. In this article I'll show you how to add some useful repositories to your Ubuntu distribution.

First, we have to backup our sources.list by typing in terminal:

# sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak

To add extra repositories proceed with the next steps.

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How To Set Up a FreeBSD Router – Step-by-Step Tutorial

This tutorial explains how to set up a FreeBSD system that will act as a network router that takes advantage of the ported version of OpenBSD's PF packet filter. A network router is a system that forwards packets from one interface to another.

1. FreeBSD Installation

Install FreeBSD by using this tutorial.

Now that you have FreeBSD installed, lets proceed with the next step.

2. FreeBSD Network Configuration

Open /etc/rc.conf in your favorite editor. You need to add a line for each network card present on the system, for example in our case we'll use two network cards:

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How To mount ISO images in FreeBSD and Linux

An ISO image is an archive file (disk image) of an optical disc using a conventional ISO (International Organization for Standardization) format. ISO image files typically have a file extension of .ISO.

The name "ISO" is taken from the ISO 9660 file system used with CD-ROM media, but an ISO image can also contain UDF file system because UDF is backward-compatible to ISO 9660.

1. Procedure to mount ISO images under Linux

You can mount an ISO image via the loop device under Linux. It's possible to specify transfer functions using loop device.

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How To keep ports collection up to date in FreeBSD

The FreeBSD Ports collection is a package management system for FreeBSD which provides an easy way of installing software packages on the FreeBSD operating system.

1. Updating the ports collection

a.) Using CVSup method

This is a quick method of getting and keeping your ports collection up to date using cvsup protocol. Make sure /usr/ports is empty before you run cvsup for the first time.

If you never updated ports collection you have to install cvsup utility:

# pkg_add -r cvsup-without-gui

Update ports collection:

# cvsup -L 2 -h /usr/share/examples/cvsup/ports-supfile

Above step will take some time to fetch the files.

b.) Using portsnap method

Portsnap is an alternative system for distributing the ports collection.

Install portsnap with the following command:

# pkg_add -r portsnap

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How To Set Up a NFS Server in FreeBSD

Network File System (NFS) is a network file system protocol originally developed by Sun Microsystems in 1984, allowing a user on a client computer to access files over a network in a manner similar to how local storage is accessed.

1. Setting up a NFS Server

The first step to setting up a NFS server is to edit the /etc/rc.conf file and add the following lines:

nfs_server_flags="-u -t -n 4"

Next, you have to set up /etc/exports file to define which machines have permission to which folders.  The exports file looks something like this:

/data -maproot=user1 host1 host2 host3
/backup -alldirs host1 host2 host3
/store host2

In this example the machines host1,host2 and host3 are given the privileges of the user1 for the /data directory.

For /backup they are given access to read from all directories within backup. And for /store only host2 is given access to read just the /store directory (make sure you replace hosts with your desired host names).

To start NFS server, enter:

nfsd -u -t -n 4
mountd -r

2. Restarting the NFS Server

Once you have made changes to the exports file you need to restart NFS for the changes to take effect:

kill -HUP `cat /var/run/`
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MySQL Server Installation in FreeBSD using ports

This guide describes how to install MySQL, a very popular relational database, in FreeBSD.

Please make sure the ports collection is up to date. If not, run the following command:
# portsnap fetch update

Then navigate to the ports folder for MySQL:
# cd /usr/ports/databases/mysql51-server
and run:
# make install clean
This command will download required files from the internet and will install MySQL server.

Once the install is finished, we install the database
# mysql_install_db --user=mysql
and we set up the directory permissions
# chown -R mysql /var/db/mysql/
# chgrp -R mysql /var/db/mysql/

Make sure MySQL server start automatically whenever FreeBSD comes up after reboot.
FreeBSD provide this facility via system configuration information. This file lists which services should be started up at system initial boot time.
The file contains the global system configuration information referenced by the start up scripts and is stored in /etc/rc.conf.

Configure FreeBSD to start MySQL at start up
Open /etc/rc.conf file using a text editor ( I use vi but you can use your preferred editor )
# vi /etc/rc.conf
and append following line which will enable MySQL server automatically after each reboot:
Save file and exit to shell prompt.

Starting MySQL server
To Start MySQL server under FreeBSD type following command (use script):
# /usr/local/etc/rc.d/ start

Note: This will work only if you have mysql_enable="YES" in rc.conf. If you don't, use the following command:
# /usr/local/etc/rc.d/ forcestart

MySQL Password
By default, MySQL super user account has no password. So it’s important to assign the administrator account password. To change the root password, enter the following command:
mysqladmin -u root password newpass

Replace newpass with your own desired password.

Optionally, copy either my-huge.cnf, my-large.cnf, my-medim.cnf or my-small.cnf  (depending on the usage and utilization of your MySQL server) as my.cnf to /etc/ or /var/db/mysql which will enable you to tweak and change the configuration of server-specific MySQL server options by editing the file.

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How To Improve the Speed of Firefox 3 in Linux

We all know Firefox is a memory hog. To speed things up, do the following:

Open Firefox and type about:config in the address bar.
Click the “I’ll be careful, I promise“ button
Use the search bar above to look for network.http.pipelining and double click on it to set it’s value to True.
Create a new boolean value named network.http.pipelining.firstrequest and set it to True.
Find network.http.pipelining.maxrequests and change its value to 8.
Look for network.http.proxy.pipelining and set it to True.
Create two new integers named nglayout.initialpaint.delay and content.notify.interval, set them to 0.
Restart your browser.


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FreeBSD: How To Upgrade FreeBSD 7 to 8 Stable Release

FreeBSD 7.x allows upgrade of existing installation to FreeBSD 8.0-STABLE. Since this is a major version upgrade, it is recommended that you backup your data, database and configuration files.

This guide will walk a user through updating his source to follow FreeBSD's stable branch.  Please make a full backup of the current system before following this guide.

STEP 1: Syncing the source tree

- cvsup installation and configuration

# cd /usr/ports/net/cvsup-without-gui

# make install clean


# pkg_add -r cvsup-without-gui

Copy the sample supfile for Stable to /usr/local/etc/stable-supfile:

# cp /usr/share/examples/cvsup/stable-supfile /usr/local/etc/

Edit file and set host name which specifies the server host which will supply the file updates to your system.


Set release tag to stable 8:

*default release=cvs tag=RELENG_8

Run cvsup to download the latest stable source:

# cvsup -L 2 /usr/local/etc/stable-supfile

When the cvsup has completed, change to the /usr/src directory

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FreeBSD: How To boot kernel.old

If you want to boot with an old kernel, because the current one is not working properly, this is what you have to do:
During boot you get a message like:
"Booting kernel in 10 seconds or press enter..."
Just hit any key except the ENTER key and you'll get a prompt.
Type 'unload all' and then 'boot [kernel file]' where [kernel file] is the kernel you want
to boot e.g. 'kernel.old' .

Your FreeBSD machine will boot with the kernel you specified.

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