Sometimes it is necessary to have all files in a folder to be created with the same group and permissions. This is most useful where multiple users have access to a shared folder, and all those users need to be able to access any files created there. Firstly all the users should be members of... Read More >>

For the past year I've been working on a Mac Mini, but it didn't really work for me, so I've moved back to my trusty Linux box which is a much better place to run the open source software that I use. One of the things that I do like about the Mac is the... Read More >>

At the moment about 90% of our SPAM is coming from India and China (The Russians seem to be on holiday). Of the Indian SPAM, the majority originates from airtelbroadband.in Like many ISPs Airtelbroadband don't seem  to care that they are being used to send spam. Sometimes our only recourse is to reject all emails... Read More >>

Find is a really useful tool. I must use it many times every day. Here are some useful examples: Finding all files matching find all directories in current folder $ find . -type d find all files: $ find . -type f Find all .php files $ find . -type f -name "*.php" Find all... Read More >>

Do you ever find that your server performance has suddenly taken a nose dive ? One of the most common causes of this is a brute force attack on your web server. You can quickly determine if this is the case by using top or ps. It is often caused by a small number of... Read More >>

We use Spamassin and Amavis to keep control of spam being sent to our users. These use blacklist services to help determine if a message is a spam. The blacklists keep a list of servers that are known to regularly send SPAM. If the sending server gives a positive match on a black list it... Read More >>

If you have a problem logging into WHM as root, and get the following message: The login is invalid This could be because brute force protection is enabled and you are being blocked by the server. You can disable it as root from the command line as follows:  Get the process id's of any cphilkd... Read More >>

Sometimes you need to block a server that is repeatedly probing your server, trying to brute-force crack authentication details. As a quick short-term fix, the easiest way to block them is simply to block them with the firewall: iptables -I INPUT -s 1.2.3.4 -j DROP Using DROP rather than REJECT will give them delays, causing... Read More >>

Once you have it running postfix rarely needs any needs much looking after. This means that when you do get an issue, you may be a bit rusty about what to do to fix things. Here are a few pointers to a few commands that can help. We are running debian 7.6 (wheezy) on our... Read More >>