We have been looking at the Nagios monitoring solution for the last few weeks and wanted to add some way of sending SMS alerts out to phones for critical events that require immediate notification. Nagios is a polling process that pulls the status at regular intervals so have a critical failure between pools could be a problem. We looked at adding an interface to use the Twillo SMS product but wanted to ensure we could use the 5250 interface for normal configuration and processing. Twillo is also a costed service so we felt that adding that cost might put some people off the monitoring solution .
We had seen that most phone providers have a web based interface to allow free messages to be sent to phones and after some digging we found that there is a list of the email addresses that can be used to send SMS text via email. In our case the provider we use for our phones is bell.ca so the email address we need to send to would be email@example.com. There are many others available and a quick google search will provide you with a list.
We already have an email process built into our HA4i product, this was to form the basis of a new application that would allow the SMS message to be built and sent out via a configured email server (see our previous post about setting up relaying on our internal server might be interesting if like us, you need to relay mail from an internal server). We have built a number of new interfaces to allow address book maintenance and provider maintenance etc via 5250 which will hopefully make it easy to use. The original email functions had to be altered slightly to function with SMS (we changed the headers slightly just for SMS) but overall everything bolted together nicely and we now have the ability to send SMS messages from our IBM i for free! (we have an unlimited text plan thankfully)
We still have a long way to go before it will be ready for integration into our other products but we feel we have now the base to build upon. Next stage is to build the local monitoring processes so they can react to critical problems and send out the notifications to SMS targets or email targets plus feed the status back to Nagios.