THE MYTH OF THE: Blank Push in macOS

[mhegge]

Doesn't work, never has. Change my mind.

[rhooper]

I have never seen any logs for it so does that mean it is not working?

[mm2270]

It might depend on what it is that we're expecting to happen when the feature is used. So, what exactly do you expect to see happen when invoked that isn't happening?

[isThisThing0n]

I thought it forced a check in via MDM. Just a empty payload but would refresh any pending commands. I often run it after cancelling failed commands as a matter of process rather than based on any solid evidence it actually did anything.

[mm2270]

Yeah, that's what it's supposed to do as I understand it, but I'll be honest, I can't actually say I have any hard evidence that it does that, so I don't have a way to counter anyone's thinking here. Maybe someone at Jamf can enlighten us on its proper use. It should cause any pending commands to kick in, but I'm not sure.

[utkec]

The blank push management command for computers (and mobile devices) sends a blank push notification to the device prompting it to check in with Apple Push Notification service (APNs). The feature can be useful to test if a device is having issues communicating with Jamf Pro or APNs.

[mm2270]

Thanks for the quick reply to this thread @casey.utke! So, by checking in with APNs, does this mean any type of pending MDM commands (assuming there even are any) would kick in? In most cases it's rare to have too many pending commands unless there is some kind of communication issue between the device, APNs and the Jamf server. But assuming there are any, and communication is working as expected, would it, or should it cause them to take place?

[utkec]

I would assume so as if the blank push is successful as that means the device was able to talk to Jamf Pro and APNs in which case the pending commands should also be able to go. That being said there is the possibility something else could be causing the pending commands.

[Naren]

I'm intrested to know what is the exact command that sent to device from jamf when we click on blank push?

[bradtchapman]

It would be more useful if the blank push actually gave real-time feedback in the console.

[isThisThing0n]

It’s a layer of abstraction that we may never fully understand!

[mhegge]

@bradtchapman Exactly!

[elsmith]

I'm with @bradtchapman on that one... it could at least put an entry in the log so you know if it worked or not. I usually want to run it when I see a bunch of pending or failed commands, but the fact that it doesn't show up in logs or tell you it's successful/failed in any way makes it pretty worthless to us.

[thetfordb]

run this in terminal and you'll see the activity from a blank push.

log stream --predicate 'process="mdmclient"'

[user-bmLAgfrTvn]

If it does cause an Inventory Check - I wonder why there is a specific management command for Inventory Check for devices.
And also asks the question: why isn't there a similar command for Computers?

[ShaneY]

If its not been said you can enable MDM debugging on a machine, do a blank push and see that it arrived at the machine.  This verifies that the communication channel is open and working.  It does nothing else.