Accessing server vhosts on the VirtualBox guests

This post will probably help you, if you are searching for way to access an Apache/Nginx vhost on VirtualBox's guest. Let's assume we have vhost mega8080 listening on port 8080. The following makes it available for Windows XP guest.

Edit vhost configuration

Vhost configuration file like /etc/apache2/sites-available/localhost should listen to port 8080:

ServerName server.megahost
NameVirtualHost 127.0.0.3:8080


DocumentRoot /var/www/megahost8080
ServerName megahost8080

Register IP

In our sample /etc/hosts should have the following like:

127.0.0.3	megahost8080

Relay port 8080 connections to IP 127.0.0.3

# iptables -t nat -I PREROUTING -p tcp --dport 8080 -j DNAT --to-destination 127.0.0.3
# iptables -t nat -A OUTPUT -p tcp --dport 8080 -j DNAT --to-destination 127.0.0.3

We need this because in Windows XP ipconfig outputs:

IPv4Address: 10.0.2.15
Default Gateway: 10.0.2.2

We need port forwarding because it won't work if configure our vhost to listen to 10.0.2.15 directly.

Simplest way to configure network for guest is to keep it's default NAT configuration :)

Network adapter: 
 - attached to: NAT 
 - type: PCnet-FAST III (NAT)

Forward port 8080 connections through TCP in VBox

$ VBoxManage setextradata "winxp" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/http/Protocol" TCP
$ VBoxManage setextradata "winxp" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/http/GuestPort" 8080
$ VBoxManage setextradata "winxp" "VBoxInternal/Devices/pcnet/0/LUN#0/Config/http/HostPort" 8080

Or, in new versions, just set it up via GUI: Settings - Network - Port Forwarding.

Bind guest IP to the hostname

File C:\windows\system32\drivers\etc\hosts(or similar) should contain line like the following:

10.0.2.2	megahost8080

Test it

Go to http://megahost8080:8080

Upgrading to Newest Version of an App Which Still Is Not Available In the Gentoo Portage

Sometimes you need new version of an app, but it is not yet availlable via Gentoo's portage(or overlays). If you want to keep things organized, you have to make package yourself. In some distros it is done easily with `checkinstall` utility, which helps to produce Debian, RPM or Slackware packages. In Gentoo we have make a ebuild ourselves.

However, ebuild tool and existing ebuilds in PORTDIR(usually /usr/portage) make it pretty easy too. I'll show it with example.

Let's say, I have to upgrade app-misc/sphinx to version 2.0.6. But even after emerge --sync the latest ebuild available is /usr/portage/app-misc/sphinx/sphinx-2.0.5.ebuild. For this, we'll do the following: 1) Add our custom portage directory 2) Copy and modify sphinx-2.0.5.ebuild in our brand new portage dir 3) emerge the new version, pulling the code from the official application maintainer's site

Add new portage overlay dir:

# mkdir -p /var/lib/layman/my_ebuilds
# vim /etc/portage/make.conf
# ...
PORTDIR_OVERLAY="${PORTDIR_OVERLAY} /var/lib/layman/my_ebuilds"
# ...

Copy existing ebuild:

# cp /usr/portage/app-misc/sphinx/sphinx-2.0.5.ebuild /var/lib/layman/my_ebuilds/app-misc/sphinx/sphinx-2.0.6.ebuild
# vim /var/lib/layman/my_ebuilds/app-misc/sphinx/sphinx-2.0.6.ebuild
... change version, URIs etc. if needed (in my case it detects version automatically)

Build ebuild manifest(this will fetch file from the Web):

# cd /var/lib/layman/my_ebuilds/app-misc/sphinx
# ebuild sphinx-2.0.6.ebuild manifest

Finally upgrade to the new version:

# emerge -Duva app-misc/sphinx

That's it! Enjoy:)

References

1. Gentoo WIKI: Writing Ebuilds

Speeding Up Copy Process Between Two Hard Drives

cp command is not suitable for large data transfers between two hard drives. It makes about 10..100KB/sec. Obviously, it will take 29 hours to copy 10GB with 100KB/sec.

There are many ways to speed up copying process -- using USB, Firewire, Ethernet etc. But if everything is done on a local machine, rsync is very effective and simple to use. For example, the following shows how to copy files over the virtual loopback device:

$ mkdir -p /mnt/hdd
$ sudo mount /dev/sdbX /mnt/hdd
$ rsync -az user@localhost:/some/folder/* /mnt/dest-hdd/

a("archive mode") option takes care of permissions, ownership, group, symlinks and so. z instructs rsync to use compression.

/var/run/mysqld is removed after each reboot?

After recent upgrade on my Gentoo box I've accidently got /var/run/mysqld directory removed. The socket path pointed there, and, of course, mysqld denied to launch. The same thing happened some time ago on Ubuntu and openSUSE. I've no clue what makes it(mysqld? rc script?) remove the directory. But I've got at least two simple fixes for that and wanna share it in this post.

Fix #1

Just change path to the socket in /etc/mysql/my.cnf and get rid of these upgrade issues:

socket = /tmp/mysqld.sock

I have it in client and mysqld sections.

Fix #2

Change the runlevel script. In Gentoo it looks like the following:

checkconfig() {
    if [ ! -d /var/run/mysqld ] ; then
        checkpath -d -m 755 -o mysql:mysql /var/run/mysqld
    fi
    if [ -z "${MYSQL_PERMS_OK}" ] && [ "$(stat -c %a /var/run/mysqld)" != "755" ] ; then
        ewarn "mysqld run dir is not world readable, you should reset the perms:"
        ewarn "chmod 755 /var/run/mysqld"
        ewarn "To disable this warning, set 'MYSQL_PERMS_OK' in /etc/conf.d/mysql"
    fi
}
start() {
    checkconfig
    # ...
}

You should have got it. checkconfig is called on at the very beginning of /etc/init.d/mysql start handler.

That's it. I hope this saves someone's time.

Installing ImageMagick with DejaVu support

I've had troubles with DejaVu fonts in ImageMagick. Almost everything with -font 'DejaVu-Sans-Condensed' failed. Well, it was searching for the font, consuming much of CPU resources, and used default one afterwards. In this post I'll show how to compile ImageMagick from source with DejaVu support. Althouth it may seem trivial, the process may sometimes be tricky.

First off, install FreeType dev package. It should be called libfreetype*-dev or so. For instance, in Debian:

$ sudo apt-get install libfreetype6-dev

Make sure you have DejaVu font installed. Package name should be named somewhat like 'ttf-dejavu'. In Debian you can install it as follows:

$ sudo apt-get install ttf-dejavu-core ttf-dejavu ttf-dejavu-extra

Download the source

Download tarball from http://www.imagemagick.org/script/download.php and unpack it.

Find font directories

Figure out the main directory with fonts and a directory with DejaVu fonts, and specify them in configuration:

$ ./configure --with-freetype=yes --with-djvu=yes \
--with-fontpath=/usr/share/fonts/truetype \
--with-dejavu-font-dir=/usr/share/fonts/truetype/ttf-dejavu 

Compile and install:

$ make
$ sudo make install 
# or 
# sudo make checkinstall
# whatever preferred/appropriate.

ldconfig

I had to make the follownig for my /usr/local prefix:

$ sudo ldconfig

Likely, you should do it also.

Verify

Verify that ImageMagick recognizes DejaVu:

$ identify -list font | grep -i dejavu

This should output a list with installed DejaVu fonts.

I hope this will be helpful for someone.

eio - a new PHP extension for asynchronous POSIX I/O

Eio is a new PECL extension for asynchronous POSIX I/O.

Eio provides interface for the libeio library. It means that each POSIX call runs in a separate thread. It is important to aware that the order of ungrouped requests is not precisely known. However, libeio, as well, as eio, supports complex call creation to accumulate a set of regular eio_* requests in a single group request. This allows to create a group request ex. to open, read and close a file.

Currently Windows platforms are not supported.

Any extension-specific suggestions are welcome :)

Creating new Vim filetype for server logs

In this post I'll show how to create a simple Vim syntax script to highlight source of common error and access logs.

First make sure you have the following folders and files:

~/.vimrc		- the main config
~/.vim/ftdetect		- directory with filetype scripts
~/.vim/syntax		- directory with specific syntax scripts

If something missing, you can copy it from $VIMRUNTIME directory. Find block starting with

if has("autocmd")

and add the following line there:

au BufRead,BufNewFile *.log set filetype=error_log

Create filetype script in ~/.vim/ftdetect/error_log.vim:

if did_filetype()	" filetype already set..
	finish		" ..don't do these checks
endif


au BufRead,BufNewFile *.error.log set filetype=error_log
au BufRead,BufNewFile *.access.log set filetype=error_log

Finally you need syntax script itself, ~/.vim/syntax/error_log.vim:

" Vim syntax file
" Language:    error_log
" Maintainer:  Ruslan Osmanov <rrosmanov at gmail dot com>
" Last Change: Thu Sep  1 15:30:52 MSD 2011
" Version:     1.0

if version < 600
  syntax clear
elseif exists("b:current_syntax")
  finish
endif

" Always ignore case
syn case ignore

" General keywords which don't fall into other categories
syn keyword error_logKeyword 			error warning notice 

" Special values
syn keyword error_logSpecial         	referer client

" Strings (single- and double-quote)
syn region error_logString           start=+"+  skip=+\\\\\|\\"+  end=+"+
syn region error_logString           start=+'+  skip=+\\\\\|\\'+  end=+'+

" Numbers and hexidecimal values
syn match error_logNumber            "-\=\<[0-9]*\>"
syn match error_logNumber            "-\=\<[0-9]*\.[0-9]*\>"
syn match error_logNumber            "-\=\<[0-9][0-9]*e[+-]\=[0-9]*\>"
syn match error_logNumber            "-\=\<[0-9]*\.[0-9]*e[+-]\=[0-9]*\>"
syn match error_logNumber            "\<0x[abcdefABCDEF0-9]*\>"

" IP addresses
syn match error_logIP            	"-\=\<[0-9]*\.[0-9]*\.[0-9]*\.[0-9]*\>"

syn region error_logOperator         start="referrer\:" end="" contains=ALL

" URI
syn match error_logURI            	"http\:\/\/[^ ]*"

" Date 
syn match error_logDate 			"\[[0-9]*\/[a-zA-Z]\{3\}\/\d\{4\}:\d\{2\}:\d\{2\}:\d\{2\} +\d\{4\}\]"
syn match error_logDate				"\[[a-zA-Z]\{3\} [a-zA-Z]\{3\} \d\{2\} \d\{2\}:\d\{2\}:\d\{2\} \d\{4\}\]"

" Domain
syn match error_logDomain            "\(www\.\)\?[a-z0-9\-\_]*\.\(ru\|com\|by\|uz\|ua\|kz\|su\|net\|org\)"

" Define the default highlighting.
" For version 5.7 and earlier: only when not done already
" For version 5.8 and later: only when an item doesn't have highlighting yet
if version >= 508 || !exists("did_error_log_syn_inits")
	if version < 508
		let did_error_log_syn_inits = 1
		command -nargs=+ HiLink hi link <args>
	else
		command -nargs=+ HiLink hi def link <args>
	endif

	HiLink error_logKeyword         Statement
	HiLink error_logIP				Type
	HiLink error_logSpecial  	    Special
	HiLink error_logString          String
	HiLink error_logNumber          Number
	HiLink error_logDate			Comment 
	HiLink error_logURI				Underlined 
	HiLink error_logDomain			Underlined 

	delcommand HiLink
endif

let b:current_syntax = "error_log"
" vim:sw=4: