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Content tagged with: Centos

Setting up NAT and port forwarding to connect to a VirtualBox virtual machine for LAMP development

Eric's picture
Submitted by Eric on Sun, 09/13/2009 - 14:16

I recently got a new MacBook Pro laptop (awesome!) and went through my usual rigmarole of setting up a new [VirtualBox] virtual machine for LAMP development. In previous situations I used bridged network connections which allow my virtual machine to have its own network connection, and acquire an IP address via DHCP. Now that I plan on being more mobile, I was concerned about having a static IP address for my virtual machine (for samba connections, scripting, and any other processes that relies on a static IP address). I decided to explore alternative virtual network connections and changed my virtual NIC to use NAT (the default network connection for VirtualBox). This configuration establishes a virtual NAT for your virtual machines which is great, but the downside is I know have to setup port forwarding to connect to my virtual machine. In bridged network configurations, I could simply SSH or use Samba to connect to my virtual machine by IP address. With NAT I have to setup port forwarding for the services I need to connect to. Initially I decided to setup port forwarding for SSH (port 22) and HTTP (port 80). While my virtual machine was powered down, I executed the following commands. NOTE: you'll have to replace "Centos" with the name of your virtual machine.

$ VBoxManage setextradata "Centos" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/Protocol" TCP
$ VBoxManage setextradata "Centos" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/GuestPort" 22
$ VBoxManage setextradata "Centos" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guestssh/HostPort" 2222
$ VBoxManage setextradata "Centos" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guesthttp/GuestPort" 80
$ VBoxManage setextradata "Centos" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/guesthttp/HostPort" 8080

Now, I can SSH to my virtual machine..

$ ssh -p 2222 Eric@localhost

Or, connect to Apache by browsing to http://localhost:8080

The benefit of this network configuration allows me to travel anywhere with my laptop, use any type of network connection, and not have to worry about changing the way I connect to my virtual machine for development.

Upgrading PHP to version 5.2.6 on Centos via YUM

Eric's picture
Submitted by Eric on Thu, 08/20/2009 - 08:27

This morning, I encountered a PHP fatal error on my development environment. Upon further inspection, one of my third party modules (XML Sitemap) required a later version of PHP. A fresh installation of Centos 5.3 comes with version 5.1.6 of PHP. Here is an easy way to upgrade PHP to a later version by using the Utter Ramblings Yum repository.

I created a new yum repo file:

$ sudo emacs /etc/yum.repos.d/utterramblings.repo

# FILE CONTENTS - START
[utterramblings]
name=Jason's Utter Ramblings Repo
baseurl=http://www.jasonlitka.com/media/EL$releasever/$basearch/
enabled=1
gpgcheck=1
gpgkey=http://www.jasonlitka.com/media/RPM-GPG-KEY-jlitka
# FILE CONTENTS - END

Ran a yum update:

$ sudo yum update
# ...snip...
Updated: apr.i386 0:1.2.12-2.jason.1 apr-util.i386 0:1.2.12-5.jason.1 curl.i386 0:7.15.5-2.1.el5_3.5 httpd.i386 0:2.2.8-jason.3 ksh.i386 0:20080202-2.el5_3.1 mod_ssl.i386 1:2.2.8-jason.3 mysql.i386 0:5.0.58-jason.2 mysql-server.i386 0:5.0.58-jason.2 pcre.i386 0:7.6-jason.1 php.i386 0:5.2.6-jason.1 php-cli.i386 0:5.2.6-jason.1 php-common.i386 0:5.2.6-jason.1 php-gd.i386 0:5.2.6-jason.1 php-mbstring.i386 0:5.2.6-jason.1 php-mssql.i386 0:5.2.6-jason.1 php-mysql.i386 0:5.2.6-jason.1 php-odbc.i386 0:5.2.6-jason.1 php-pdo.i386 0:5.2.6-jason.1 php-pear.noarch 1:1.6.2-1.jason.1 php-xml.i386 0:5.2.6-jason.1 php-xmlrpc.i386 0:5.2.6-jason.1 subversion.i386 0:1.4.4-jason.1 tzdata.noarch 0:2009k-1.el5
Complete!

After updating all these packages, I checked out my new PHP version:

$ php -v | head -1
PHP 5.2.6 (cli) (built: May  5 2008 10:32:59)

Now, my PHP fatal error has been resolved.

NOTE: This blog entry is a re-post of a previous article.

Resolving the "Call to undefined function timezone_open()" PHP fatal error in the date_api module

Eric's picture
Submitted by Eric on Thu, 01/08/2009 - 12:05

I just encountered a PHP fatal error when running my cron.php:

Fatal error: Call to undefined function timezone_open() in /MYSERVERPATH/httpdocs/sites/all/modules/date/date_api.module on line 607

A quick Google search, and I found the issue is documented here. The solution is to enable the Date PHP4 module. But, this issue does not happen in our production environment, so I decided to compare PHP versions:

# on the production server:
$ php -v | head -1
PHP 5.2.8 (cli) (built: Dec  9 2008 14:03:11)

It turns out, a fully updated installation of Centos 5.2 only supplies PHP 5.1.x. So, I decided to upgrade PHP in my development environment according to this documentation.

I created a new yum repo file:

$ sudo emacs /etc/yum.repos.d/utterramblings.repo

# FILE CONTENTS - START
[utterramblings]
name=Jason's Utter Ramblings Repo
baseurl=http://www.jasonlitka.com/media/EL$releasever/$basearch/
enabled=1
gpgcheck=1
gpgkey=http://www.jasonlitka.com/media/RPM-GPG-KEY-jlitka
# FILE CONTENTS - END

And, ran another yum update:

$ sudo yum update
# ...snip...
Resolving Dependencies
# ...snip...
Dependencies Resolved

=============================================================================
Package                 Arch       Version          Repository        Size
=============================================================================
Updating:
apr                     i386       1.2.12-2.jason.1  utterramblings    257 k
apr-util                i386       1.2.12-5.jason.1  utterramblings    159 k
httpd                   i386       2.2.8-jason.3    utterramblings    2.5 M
mod_ssl                 i386       1:2.2.8-jason.3  utterramblings    314 k
mysql                   i386       5.0.58-jason.2   utterramblings    6.4 M
mysql-server            i386       5.0.58-jason.2   utterramblings     10 M
pcre                    i386       7.6-jason.1      utterramblings    562 k
php                     i386       5.2.6-jason.1    utterramblings    3.7 M
php-cli                 i386       5.2.6-jason.1    utterramblings    2.6 M
php-common              i386       5.2.6-jason.1    utterramblings    481 k
php-devel               i386       5.2.6-jason.1    utterramblings    568 k
php-gd                  i386       5.2.6-jason.1    utterramblings    320 k
php-ldap                i386       5.2.6-jason.1    utterramblings     56 k
php-mbstring            i386       5.2.6-jason.1    utterramblings    1.3 M
php-mssql               i386       5.2.6-jason.1    utterramblings     61 k
php-mysql               i386       5.2.6-jason.1    utterramblings    258 k
php-odbc                i386       5.2.6-jason.1    utterramblings    112 k
php-pdo                 i386       5.2.6-jason.1    utterramblings    159 k
php-pear                noarch     1:1.6.2-1.jason.1  utterramblings    418 k
php-soap                i386       5.2.6-jason.1    utterramblings    342 k
php-xml                 i386       5.2.6-jason.1    utterramblings    316 k
php-xmlrpc              i386       5.2.6-jason.1    utterramblings    130 k
subversion              i386       1.4.4-jason.1    utterramblings    4.3 M

Transaction Summary
=============================================================================
Install      0 Package(s)        
Update      23 Package(s)        
Remove       0 Package(s)        

Total download size: 35 M
Is this ok [y/N]:

After updating all these packages, I checked out my new PHP version:

$ php -v | head -1
PHP 5.2.6 (cli) (built: May  5 2008 10:32:59)

Now, my PHP fatal error has been resolved :)

Creating and configuring a virtual machine for LAMP development

Eric's picture
Submitted by Eric on Wed, 01/07/2009 - 10:45

After losing my development virtual machine yesterday, I thought I'd document my process for creating a new one. The first thing to do is download your favorite Linux distribution. I prefer Centos (RHEL without the support contract) but what's most important is creating one that's as close to your production environment as possible (to avoid package version differences, differences in documentation, and deployment issues). The second step is creating a new virtual machine and defining it's properties. For a basic development system, I give it 512MB of RAM and a large enough hard drive for your projects. After defining it's properties, point the CDrom drive at your downloaded Linux distribution ISO and install the operating system. Here's the fun part, getting everything to work...

Update your packages

$ yum update

Install your favorite text editor

$ yum install emacs

Configure sudo so you don't have to use root (in: /etc/sudoers)

%wheel ALL=(ALL) NOPASSWD: ALL

Create a new user for yourself, and set your new password

$ adduser Eric
$ passwd Eric
# NOTE: add your user to the wheel group in /etc/group so you can setup sudo
# NOTE: add your user to the apache group and vice versa
# NOTE: from now on, log in as your user and use sudo to execute commands that require root privileges

Install subversion

$ sudo yum install subversion

Install mysql

$ sudo yum install mysql-server

Install PHP

$ sudo yum install php php-cli php-common php-devel php-gd php-ldap php-mbstring php-mssql php-mysql php-odbc php-pear php-soap php-xml php-xmlrpc
# NOTE: The previous command will automatically install Apache (httpd) as a dependency

(OPTIONAL) upgrade PEAR packages

$ sudo pear upgrade-all

(OPTIONAL) install additional PEAR packages

$ sudo pear install DB HTML_QuickForm Mail Mail_Mime

(OPTIONAL) install openssl for HTTPS traffic

$ sudo yum install mod_ssl openssl

Set run levels for mysql and apache to ensure the services start automatically

$ sudo /sbin/chkconfig --level 2345 httpd on
$ sudo /sbin/chkconfig --level 2345 mysqld on

Set MySQL passwords

# root password:
$ /usr/bin/mysqladmin -u root password 'YOUR-NEW-PASSWORD'

# your user:
$ mysql -u root -p
mysql> grant all privileges on *.* to 'Eric'@'localhost' identified by 'YOUR-NEW-PASSWORD' with grant option;

# (OPTIONAL) you can add privileges for your user to connect from other computers:
mysql> grant all privileges on *.* to 'Eric'@'%' identified by 'YOUR-NEW-PASSWORD' with grant option;

Configure PHP (edit /etc/php.ini)

$ sudo emacs /etc/php.ini
display_errors = [Off per prod | On per dev/test]
error_reporting = E_ALL & ~E_NOTICE
memory_limit = 100M
upload_max_filesize = 100M
post_max_size = 100M

Configure Apache

# create a directory for all your vhosts, and set permissions
sudo mkdir /var/www/vhosts
sudo chown -R Eric.Eric /var/www/vhosts
sudo chmod -R 2770 /var/www/vhosts

# create a new configuration file to keep your changes separate from httpd.conf
$ sudo emacs /etc/httpd/conf.d/Eric.conf

# FILE CONTENTS - START

# set directory indexes to ensure php files are not read as text
DirectoryIndex index.php index.html index.html.var index.htm

# set a default character set
AddDefaultCharset ISO-8859-1

# enable name based virtual hosts, so you can host multiple hostnames on one server
NameVirtualHost *:80

# I create a separate directory for all my virtual hosts. This allows .htaccess files to work properly
<Directory /var/www/vhosts>
AllowOverride All
</Directory>

# add your first virtual host entry
<VirtualHost *:80>
ServerName SITEHOSTNAME
DocumentRoot /var/www/vhosts/SITEHOSTNAME/httpdocs
ErrorLog logs/SITEHOSTNAME-error_log
CustomLog logs/SITEHOSTNAME-access_log common
</VirtualHost>

# FILE CONTENTS - END

Configure MySQL (edit /etc/my.cnf)

[mysqld]
set-variable = max_allowed_packet=32M

Start Apache & MySQL

$ /etc/init.d/mysqld start
$ /etc/init.d/httpd start

(OPTIONAL) Configure Samba so you can edit your virtual machine filesystem from your host operating system
[documentation here]

Now, from your host operating system, edit your /etc/hosts file and point your development hostname to the new IP address of your virtual machine. If you go to that web address you should be able to reach your Apache virtual host on your new virtual machine!

Installing from source and resolving the error: "configure: error: no acceptable C compiler found in $PATH"

Eric's picture
Submitted by Eric on Fri, 12/19/2008 - 15:30

I just went to install a package from source on my Centos linux virtual machine and got the following error:

$ ./configure
checking for gcc... no
configure: error: no acceptable C compiler found in $PATH
See `config.log' for more details.

No worries, you just need to install a C compiler. First I took a look at what's available via yum:

$ yum list | grep -i ^gcc
gcc.i386                                 4.1.2-42.el5           base           
gcc-c++.i386                             4.1.2-42.el5           base           
gcc-gfortran.i386                        4.1.2-42.el5           base           
gcc-gnat.i386                            4.1.2-42.el5           base           
gcc-java.i386                            4.1.2-42.el5           base           
gcc-objc.i386                            4.1.2-42.el5           base           
gcc-objc++.i386                          4.1.2-42.el5           base

And then install one:

sudo yum install gcc

Now, back to installing my package from source...