If you are having an issue with a slow MySQL connection to a remote database then perhaps the following can help.

Essentially my website was taking 7-8 seconds to load and the Apache logs weren’t giving me much to go on. Using a website page test tool such as http://www.webpagetest.org I could see that the site itself was performing well but there was a 7 second server wait time.

This lead my on to the assumption that the MySQL connection was causing the issue. To test, I simply created a new database locally and updated the config files. What do you know…the website loads instantly. This confirmed my assumption.

So I set about figuring out why the MySQL connection was so slow even though the remote server was within the same network. The fix is very simple:

Edit the hosts file on the remote MySQL server:

vim /etc/hosts

Add in the following line:

xxx.xxx.xxx.xxx original.host.com original 

* xxx being the IP address

The original host being the server you are connecting from. Go back and check your website hopefully everything is back to full speed.

The main reason for adding the entry to the hosts file is due to not having reverse DNS set up. Once the entry has been added manually this will do the lookup manually rather than querying the DNS.

More useful information can be found here: http://etwiki.cpanel.net/twiki/bin/view/11_32/WHMDocs/SetupRemoteMySQL

The below bash script, when executed, will check the % of disk space usuage of the complete filesystem and email a specified email address if more than 80% full.

Pre-req – create fs_report.log inside /var/log/

i.e.

 
touch /var/log/fs_report.log 

Create a new bash script:

 
vim /path/to/script/diskspace.sh 

Replace the email address or modify the disk space below as needed:

#!/bin/bash
#
#Extract % use for the filesystem
#Send email warning to if the raid is 80% or more full
#Include Folder/File sizes of the filesystem directory contents
#
df -h | awk '{ print $5 }' | cut -d'%' -f1 | while read usep; do
if [ $usep -ge 80 ]; then
echo "***$(hostname) is $usep% FULL at $(date)" > /var/log/fs_report.log
echo "***Please remove unnecessary data from $(hostname)" >> /var/log/fs_report.log
echo "***Detailed Folder/File size for BackupServer content:" >> /var/log/fs_report.log
df -h >> /var/log/fs_report.log
mail -s "WARNING-bksvr2 $usep% FULL" backup@mydomain.com < /var/log/fs_report.log -- -f "backup@mydomain.com"
fi
done

*Make sure to make the script executable:

chmod +x diskspace.sh

To automate this script add a cron job to run it on a regular basis:

0 8 * * * /path/to/script/diskspace.sh

The above cron job will run the script at 8am everyday.

This is a must have for any Smoothwall Express Setup. This mod gives you full control of your interfaces including mutliple IP addresses, ports and mac control:

The mod gives ultimate control with the following:

1. Specify origin source IP/Network
2. Specify the origin/destination ports to be open for your specific IP/Network

e.g. Open access for the IP 222.111.55.333 on port 57 to your IP xxx.xxx.xxx.xxx on port 22

To install the mod simply run the following from commandline:

wget http://storage.googleapis.com/google-code-archive-downloads/v2/code.google.com/stans-smoothwall3mods/fullfirewall-3.3.3.1-Express-3.0-i386.run
sh ./fullfirewall-3.3.3.1-Express-3.0-i386.run 

**NOTE: Smoothwall Express 3.0 should be up to and including update 9 – Maintenance > Updates.

Log back into the Smoothwall GUI and you will now see the Full Firewall Control interface.

For further reading take a look at the smoothwall community here

*This tutorial assumes that you already have Smoothwall Express installed on your hardware of choice.

With BT Infinity becoming evermore available we decided to setup and test smoothwall as our Firewall of choice. After quite a bit of head scratching we were able to get things up and running.

Once you have Smoothwall up and running access the web interface (https and port 441 – http://x.x.x.x:441) and navigate to Network > Interfaces:

Here, simply select the PPPoE as the ‘Connection method:” and save. Now navigate to Network > ppp:

Here we enter a Profile name, BT username and password and the authentication method. Above is an example of the settings we used for our BT Infinity test line.

Now navigate to Control > Home and click connect. If everything has been entered correctly you should have a Firewall protected BT Infinity line. Enjoy.

Few things to note:

• Cat 5 from white modem to smoothwall red interface
• Cat 5 from green interface into your switch or machine
• Firewall > Outgoing > Make sure 80, 443 etc. are open so you can access the outside world from behind the Firewall.

Very simple but useful command to find files over e.g. 1000kb and output to a log file:

find ./ -type f -size +1000k >> size.log