For 2023 - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.
Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!
I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Web Application Deployment module A163
Network Configuration and Security
Exercises, examples and other material relating to training module A163. This topic is presented on public courses Deploying LAMP - Linux, Apache, MySQL, Perl/PHP
, Linux Administration
, Deploying Java Applications on Linux / Unix
, Linux bootcamp
If you're running a network server, you need to configure your network. This module shows you how to do so under Linux, and to test that connection.
Related technical and longer articlesFirewall fundamentals - Linux
|Articles and tips on this subject||updated|
|4134||Setting up your MacBook Air as a mobile broadband router|
This blog tells you how to:
1. How to connect to Mobile Broadband using Huawei e156a and the latest Mac OSX software
2. How to set up Internet sharing via a mobile (3G) dongle to a local WiFi network
Upgrading a computer and / or an operating system gives improved performance and extra features, right? ...
|11||A bolt of lightning on Multicasting|
When I learnt about TCP/IP, Multicasting was a bit of a footnote in the appendix. I can appreciate that for broadcast / streaming applications it could have its use but ... in my day-to-day stuff I didn't expect to see it used "in anger". Then today I was watching a customer rebuilding 26 machines ...
|3448||Checking all the systems on a subnet, using Expect and Tk|
There are times that we want to check the connectivity of all the systems on our subnet - to see which machines are present, and which are not. Pinging them one at a time is a bit slow, but pinging them all at once in a simple script sets up too many connections and the script is likely to fall over. ...
|2489||Parallel Pinging, using Python Threads or Expect spawn lists|
Ping is a very useful command to use within scripts for checking the presence (or absence) of a live system on our network, or indeed on the Internet. However, there are subtle differences in the format of its report on different operating system flavors, so any code that you write that needs to analyse ...
|332||Looking up IP addresses|
Browsers, mail clients, ftp and ssh and telnet clients and the rest are for ever converting fully qualified names such as www.sheepbingo.co.uk into IP addresses such as 184.108.40.206. How can you do such a lookup manually?
Firstly, there are numerous web sites out there that will help you - I'm not ...
|2052||How was my web site compromised?|
It looks to me as if this car has left the road and come to a sudden halt against the building, with the result that both have been somewhat damaged. But why did it happen? Was there a mechanical failure such as brakes or tyres? Did the driver fall asleep at the wheel or something distract him? ...
|1904||Ruby, Perl, Linux, MySQL - some training notes|
We have just come to the end of a solid 12 days of training ... and we are just getting ready for the next week, with delegates arriving this evening. There's a lot going on behind the scenes, even over this weekend, with the hotel to be prepared as well as the training course. (Picture - our clean ...
|1712||As different as night and tyres|
I was going to say "as different as night and day" - but they're really too similar! You'll be reading this forum post on our new server, and I'm already seeing a dramatic improvement in performance - partly related to the heavy load on the previous server, partly because the previous server wasn't ...
|1666||Slow boot and terminal start on Linux boxes|
Now this was a mystery. I had two Linux boxes which booted perfectly when used inhouse, but very slowly indeed (10 minutes plus) when in use on a customer site. Very awkward really - we would test out the systems in Melksham and find them fine, but then they would fail in Bristol. Even calling up ...
|1408||Wireless hotel tips - FTP and Skype connections failing|
I'm on line this week through a Spectrum interactive account, who's web site tells me that they have won a contract to supply BAA at Heathrow Terminal 5 and that they have an exclusive 7 year deal at Travelodge, where I have been staying. It's not all been a bed of roses - quite apart from a major loss ...
|1073||Heartbeat script in Perl|
Scenario ... an Apache httpd web server is distributing requests around between a number of Apache Tomcat instances on different computers (perhaps using mod_rewrite to allocate the requests). If a Tomcat instance become unavailable (i.e. if the host running it is taken offline) then it's to be removed ...
|506||What are DHCP and DNS?|
Are they the same thing? Absolutely not, though both relate to resolving addresses on a network.
You can use DHCP (Dynamic Host Configuration Protocol) when you connect your client computer onto a network that it's not been pre-configured for. All computers on an IP network need to know:
a) an available ...
|511||Domain Forwarding - 2 ways of doing it|
It's always seemed to be a real hassle to move domains and DNS service from one ISP to another, and I think that's partly because the ISP that you're leaving might not want to loose business, and partly because of necessary security checks to avoid domains being stolen. But it's lead us to some interesting ...
|37||Security and Safety|
"We no longer offer that facility for [security / safety] reasons".
How many times have I been told or read that in the last few years? Am I getting to be too much of a cynic to think that the truth is more often along the lines of "it doesn't make commercial sense to provide that any more" or "it's ...
Examples from our training material
|hosts|| Archived /etc/hosts file|
Some modules are available for download
as a sample of our material or under an Open Training Notes License
for free download from [here]
Topics covered in this module
IP addressing and DNS naming.
Putting your Linux system on a network.
Testing with ping.
Using outgoing services.
If you are looking for a complete course and not just a information on a single subject, visit our Listing and schedule
Well House Consultants specialise in training courses in
Linux and LAMP
. We run
throughout the UK (and beyond for longer courses), and
at our training centre in Melksham, Wiltshire, England.
It's surprisingly cost effective to come on our public courses -
even if you live in a different
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We have a technical library of over 700 books on the subjects on which we teach.
These books are available for reference at our training centre.