Next, you configure iNag's settings on the iPhone. iNag's settings are pretty straightforward. It needs the full URL to the inag.php file, the value for either $ROkey or $RWkey, and the user name and password you'll be using to log into Nagios with iNag, as in the screenshot to the right:
: I highly recommend that you only use HTTPS to talk to Nagios, whether with iNag, or a "regular" Web browser. Depending on how your system is set up, Nagios can give an attacker a wealth of information about what's on your network, what services you're running on your network, and a logical map of your network. While there is encryption support in SNMPv3, there are a lot of platforms out there, such as switches, most printers, wireless access points, routers, and Windows that do support SNMPv3. Many of the Nagios plugins don't encrypt their data either. If you're connecting to Nagios via an unencrypted connection, and someone manages to tap into that, you could give that person a ton of information you'd rather they not have.
Once you've got the setup done (it took me about five minutes), start iNag and go. This brings me to what is my major annoyance with the application: when you first start iNag, the initial screen is not necessarily what your Nagios server sees. To see the current data, you have to hit the refresh button, and it's annoying. If I start iNag, it is a reasonable assumption that as part of that, I want it to talk to my Nagios server, and not make me hit "refresh/reload" just to get initial data. This pattern repeats throughout the application, and it just adds a thin layer of annoyance to things. However, once you hit refresh, you see a nice tactical display that gives you the overall status of what Nagios is monitoring at a glance, as shown to the right.
I scrolled down a bit to show the services more clearly. What's cut off are the number of Ok hosts. However, the overall display is clear. You can see the status of both hosts and servers. (In Nagios-speak, a host is a device on the network, and services run on a device). If you tap on the "Warning" section in Services, you're taken to a display that more clearly tells you what the problem(s) are: