Posts Tagged ‘php server’

Rsync slow data (bandwidth limit) transferring on productive Linux / *BSD servers to 2nd

Thursday, March 7th, 2013

If amount of Unique users on website has increased dramatically and Apache + PHP server starts to get user load higher than 50% in times of most users site activity then it is time to move to think of migrating data on more powerful Server hardware.

Moving few thousands of Gigabytes of PHP, JS, PNG, JPG images and plain text files data from a productive host to another puts an extra burden on hard disk Input / Output (I/O) operations, thus risking to put extraordinary server load and make websites on server inaccessible. The normal way I copy data on less busy servers is create  .tar.gz archive of data from one server and transfer with sftp or scp. In this situation, doing so however puts too much load on server and thus is risking to stone the server and make it inaccessible to users. A solution to problem is to use rsync instead, synchronizing data between the servers by instructing it to transfer data from one hard disk to another via network using a maximum read/write bandwidth.

rsync command argument specifying a maximum bandwidth is --bwlimit=KBPS

To transfer data between two servers specifyinga maximum transfer bandwidth of 10MB per second you have to pass 2MBytes as it is in megabytes (2*1024Kb) = 2048.

Hence to make the transfer while logged to current productive server via SSH to host server with IP XXX.XXX.XXX.XXX I used:
w:~# cd /home/sites
w:/home/sites# /usr/bin/rsync --bwlimit=2048 -avz -e ssh . root@XXX.XXX.XXX.XXX:/home/sites/

The arguments to above rsync command are clear enough (-e ssh) – tells to use ssh as data transfer protocol, (root@) – specifies to connect to second server with root user and (:/home/sites/) – tells rsync to transfer to remote server to same directory (/home/sites/) like from which copying.

Bear in mind that, in order this method to work, rsync has to be installed both on the server from which data is transferred and to second one to where data is transferred.
Since rsync is available in Linux as well as has port in FreeBSD / NetBSD / OpenBSD ports tree, same way to transfer "web data" while upgrading BSD OS host to another is possible.

How to get rid of “PHP Warning: PHP Startup: Unable to load dynamic library ‘/usr/lib/php5/20090626/suhosin.so'” on Debian GNU / Linux

Tuesday, October 25th, 2011

PHP-warning-how-to-fix-warnings-and-errors-php-logo

After a recent new Debian Squeeze Apache+PHP server install and moving a website from another server host running on CentOS 5.7 Linux server, some of the PHP scripts running via crontab started displaying the following annoying PHP Warnings :

debian:~# php /home/website/www/cron/update.php

PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib/php5/20090626/suhosin.so' – /usr/lib/php5/20090626/suhosin.so: cannot open shared object file: No such file or directory in Unknown on line 0

Obviously the error revealed that PHP cli is not happy that, I've previously removes the suhosin php5-suhosin module from the system.
I wouldn't have removed php5-suhosin if sometimes it doesn't produced some odd experiences with the Apache webserver.
To fix the PHP Warning, I used first grep to see, where exactly the suhosin module gets included in debian's php.ini config files. debian:~# cd /etc/php5
debian:/etc/php5# grep -rli suhosin *
apache2/conf.d/suhosin.ini
cgi/conf.d/suhosin.ini
cli/conf.d/suhosin.ini
conf.d/suhosin.ini

Yeah that's right Debian has three php.ini php config files. One for the php cli/usr/bin/php, another for the Apache webserver loaded php library/usr/lib/apache2/modules/libphp5.so and one for Apache's cgi module/usr/lib/apache2/modules/mod_fcgid.so .

I was too lazy to edit all the above found declarations trying to include the suhosin module in PHP, hence I remembered that probably all this obsolete suhosin module declaration are still present because probably the php5-suhosin package is still not purged from the system.

A quick check with dpkg , further strenthened my assumption as the php5-suhosin module was still hanging around as an (rc – remove candidate);

debian:~# dpkg -l |grep -i suhosin
rc php5-suhosin 0.9.32.1-1 advanced protection module for php5

Hence to remove the obsolete package config and directories completely out of the system and hence solve the PHP Warning I used dpkg –purge, like so:

debian:~# dpkg --purge php5-suhosin
(Reading database ... 76048 files and directories currently installed.)
Removing php5-suhosin ...
Purging configuration files for php5-suhosin ...
Processing triggers for libapache2-mod-php5 ...
Reloading web server config: apache2.

Further on to make sure the PHP Warning is solved I did the cron php script another go and it produced no longer errors:

debian:~# php /home/website/www/cron/update.php
debian:~#