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General blog posts and Google Analytics statistics

I’ve been publishing my blog for a couple of years now and thought it would be interesting to share some of the statistics that have been collected about it. My blog in mainly guides and tips for using Asterisk/FreePBX/A2Billing and also some general VOIP stuff.

Sometimes I think a blog is not the best platform for documentation. It’s a bit unstructured but I like having the date articles were published as documentation soon goes out of date.

So here are some of the figures collected by Google Analytics over the past year. I’m not sure there’s any really reliable stats systems, but Google Analytics relies on the client running Javascript so it’s probably as good as it gets.


In the past 12 months there have been around 121,000 visits, with just over 75,000 from unique IP addresses. Pretty good I think for a small blog about VOIP! The traffic is growing month on month. The busiest days are weekdays, with a slight drop off at the weekends.



There are a good proportion of visitors that return to the site. with over 46,000 IP visitors returning. Some of the how-to’s are quite long and I’m sure people have to keep re-reading to figure out exactly what I meant!

traffic source


A huge proportion of the traffic comes form Google, with other search engines way down the list. This shows just how dominant Google are in the field of search.




And I guess not surprisingly most of my viewers are not using Internet Explorer. With Firefox top and Google Chrome second in the choice of browsers. However, Google Chrome has become more popular just looking at later months, rather than back over the previous year.

So my plan is to keep writing more (hopefully!) interesting posts and we’ll see what the visitor numbers look like in another year!

A2B: Setting up a trunk in A2Billing


Setting up a trunk to your call provider in A2Billing is very straightforward if you can use IP based authentication.

All you do is go to the “PROVIDERS / Trunk / Add Trunk” menu and create a new trunk. Here you will provide the protocol used to connect the trunk (SIP/IAX2) and the IP address provided by your call termination provider –

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A2B: Whitelisting IP addresses

The A2Billing VPS template (A2B100) includes several security measures to protect your server. These include –

  • Fail2ban – which blocks IP addresses that make failed SIP registration attempts to your Asterisk server
  • Denyhosts – which blocks IP addresses that make failed SSH connection attempts to your server
  • A2Billing admin whitelisting – only specified IP addresses are allowed to connect to the A2Billing admin interface

To whitelist IP addresses so that you can access the admin interface, and prevent IP addresses from accidentally getting blocked, you can run the following script, providing it with the IP address to whitelist –

[[email protected] ~]# /usr/local/bin/

Obviously change the IP address for the one you want to whitelist.

Alternatively just open a ticket in the support system asking for this to be done.

txtlocal for SMS messages

I’ve been using for a little while now for sending SMS messages. Their website is very slick and the service works really well.

So far I’ve only used the basic e-mail to SMS but there a comprehensive API so you can integrate sending SMS messages in to your application.

The price is pretty competitive but, for me at least, the most important thing is reliability. I’ve only sent around 75 SMS messages so far but there have been no problems at all, and delivery was very quick.

There are also related services such as – inbound SMS messages, short-code numbers and MMS messages.

Check them out here –

Finally have Google Sitelinks

It’s taken quite a while (my first blog post was at the end of 2007!) but over the past couple of days Google Sitelinks have started appearing next to my site in search results.

If you don’t know what Sitelinks are they’re the direct links that come up under some websites in Google search results, link this –

google sitelinks

You can’t pay for them, and you don’t request them, Google generates them automatically when it considers your site is ‘popular’ enough.

Also, according to Google Analytics the SysAdminMan Blog receives around 20,000 pageviews and 7,000 unique visitors per month.

Allowing TFTP access on a SysAdminMan Trixbox server

By default access to UDP port 69, that is used for TFTP, is blocked by iptables (firewall) on SysAdminMan VPS server. This needs opening if you want to use Endpoint Manager to configure your compatible handsets.

When allowing TFTP access we only want to allow fixed IP addresses as there is no security provided by TFTP. You will probably also want to allow NTP (network time protocol) access to allow your Asterisk server to set the correct time on the phone, so we also open port 123.

Run the following commands while logged on as root. Replacing the address ( with your own public IP address –

# iptables -I INPUT 1 -s -p udp --dport 69 -j ACCEPT

# iptables -I INPUT 1 -s -p udp --dport 123 -j ACCEPT

# service iptables save

Saving firewall rules to /etc/sysconfig/iptables:          [  OK  ]

Swype keyboard for Android

If I had to choose my favourite Android app (and I have a lot!) it would be the Swype keyboard by far. It’s not a huge benefit for typing short words but anything over a few letters and it’s totally amazing. Just slide your fingers on the keyboard in the general direction of the letters and, more often than not, it knows what word you want.

It can definitely take some getting used to, but once you’ve got the hang of it you won’t want to switch back to a normal on-screen keyboard.

There is an open beta at the moment so why not sign up and give it a go –

Monit: Disk space monitoring

One thing you definitely don’t want to happen to your server is for it to run out of disk space, especially the root partition.

There are lots of pieces of open source monitoring software, a popular one being monit.

Below is a quick guide to installing monit and generating alert e-mails for disk space and cpu/memory usage. The installation was done on a SysAdminMan VPS running CentOS 5.5

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