It allows you to call in to your Asterisk server, get a dial tone, and then dial back out as if you were using a normal extension on your system. I use this lots to make cheap international calls from my mobile phone.
You may also wish to route your DISA calls via A2Billing. If you’ve integrated FreePBX and A2Billing as described here it’s a simple case of changing one setting on your DISA setup in FreePBX.
One of the great things about voip is that you can make international calls at local rates. Combine that with Asterisk/FreePBX and you’ve got the ability to make cheap international phone calls using your mobile phone.
To do this we’re going to setup DISA (Direct Inward System Access). This will enable us to ring our Asterisk server, get a dial tone and then dial back out again.
Then I will show you how you can combine this with callbacks if that works out cheaper for you.
Installing the modules
First we need to install the DISA (if it’s not installed already) and Callback modules. See part 5 for more information about installing FreePBX modules.
Now we can make calls to regular telephone number via our trunk we want to setup a DID (Direct Inward Dial) number so that we can receive calls from people dialing a regular phone number.
For this example I’m going to use a US number from IPKall who will provide a (free) US based telephone number. However, they are only able to do this due to a peculiarity in the law in certain states so I wouldn’t rely on the numbers being available in the future. Perfect for testing though!
I’ve been playing with OpenVPN for the past couple of weeks and I’m pretty impressed. OpenVPN allows you to create a private network between 2 computers. These could be 2 servers or a client and a server. A few of the reasons for wanting to do this are –
bypassing your ISPs traffic shaping
making your traffic appear to originate from a different country
encrypting your laptop traffic over an insecure link – such as a coffee shop wifi connection
anonymous web surfing
bypassing a countries web access controls
Setup and configuration of the server component can be fairly complicated depending how you want to manage the certificates and networking on there. It’s possible to install it on Linux or Windows although I’ve only tested it on Linux. Running the server on Linux you also need to configure iptables to translate your private ‘vpn’ ip address to an external ip address on the vpn server.
If you have your website, e-mail system, etc. running on your own VPS or dedicated server it’s good to know when that server is unavailable so you can contact your server provider asap.
The best way to do this is use an external monitoring company. I’ve been using Hyperspin for a couple of months now and it’s been working great.
You can pick what services/ports on your server to monitor (SMTP, HTTP, HTTPS, etc.) and you can chose how to be alerted when they are not available. Obviously you need to make sure that you’re alerted via an out of band method (in other words don’t rely on an e-mail to an e-mail account on your VPS to know that your VPS is down!)
The Hyperspin website isn’t very pretty but overall their system is reliable and easy to use.
Spent a little while trying to get WinPE2 (Vista) to boot via PXE from a linux server and thought it could be useful to someone. We already had our Red Hat stuff booting from there and it seemed like a good idea to keep it in one place!
Some of the stuff could be useful for booting via PXE from a Windows box too
Windows XP was used for WAIK stuff
Fedora Core 6 was used for PXE Server
Both running on VMWare Server along with a blank VMWare machine as the PXE client
* Note – there’s a bug in RHEL5 that’s stop’s the tftpd.remap file working. Not sure how many versions this affects