How to monitor an iPad ?

[ftiff]

Hi there,

I'm looking for ideas on how to monitor non-jailbroken iPads.

I could do a check_ping

How about video out? Have you heard of ways to monitor an HDMI port?

Any hints?

[eloyd]

The problem with monitoring an iPad is that unless you have an app running on the iPad that sends passive checks to the Nagios server, there is precious little you could monitor. If you know it's IP, you can ping it, as you said. That's about it. To get at anything else from the outside, you would need some sort of agent running on the device that would listen and respond. You said non-jailbroken iPads, so I doubt there is (or will be, under Apple's watch) such a thing.

Even if you did have an app that was running on it, it would have to be running in the background, consuming power while reporting to a Nagios server. The assumption is that you have 100% connectivity to the Nagios server and that you can update in real time. So what happens when you have no Internet connection? What if the Nagios server is on the other side of a firewall? Do you differentiate between wifi IPs and cellular IPs?

The topic can get complex pretty quickly, so I think your best sticking with a ping check to see if the device is active. Of course, it depends on what you want to monitor the iPad for.

[slansing]

Agree'd we'd need to know what direction you want to take, as Eloyd pointed out, an agent running on the system would use those precious little resources as well as power, and you'd want to make sure it stays on the same network, with the same address, otherwise you'll be setting up new hosts each time the DHCP reservation drops when it is offline. You'd also have to deal with batteries dying, and users shutting them off thus causing critical failure alerts on your host/services. We've also not tested any of our agents, passive or active, against the OS running on a standard iPad.

[ftiff]

Hmm it's very weird part of my post didn't go through..

So we're talking here about iPads used for display only, used in retail stores, embedded in furniture.
There's no human interaction of any kind.

The idea I had was to hook up an Apple Lighting to HDMI adapter, and monitor the actual HDMI signal: Is there any video passing through?

iPads are always on, always connected on the network.

[eloyd]

That might be VERY hard to do on the iPad directly. You would have more luck with some sort of device that plugs into the iPad and then have that device report back to Nagios. A Raspberry pi comes to mind, but it's gonna be tough either way.

[ftiff]

Yes a raspberry Pi would be a great idea… I wonder if some device already exists to do this, kind of a standalone sensor.
Pretty hard to find on google something using "HDMI" and "monitor" as keywords…

[eloyd]

You should talk to @tmcdonald about the Pi. He'll be presenting at Nagios World Conference on Nagios and Pis and Arduinos. You should talk to him about options!

[tmcdonald]

You should talk to @tmcdonald about the Pi. He'll be presenting at Nagios World Conference on Nagios and Pis and Arduinos. You should talk to him about options!

The talk is only about Arduino, but I do give a brief nod to the Pi.

If you literally only want to see if current is going through the HDMI cable, you can use a hall effect sensor to detect the magnetic field created by current going through a wire:

https://www.sparkfun.com/products/9312
https://www.sparkfun.com/products/11005

I have not tried either of those products but in theory they should do what (I think) you want. However, even a "blank" signal (all black) being sent through will trigger it - to detect video it would truly need to be displaying or not.