Re-boot requires an Encryption password.

[Android Central Question]

My phone occasionally dies and re-boots itself. If it just restarted that would be fine but it sits waiting for an encryption password. The problem is if it happens while in my pocket or while I'm asleep. I can be unavailable for several hours.

For work it's important I'm contactable 24x7. If my phone fails that's OK if it restarts and I'm only unavailable for 5-10 minutes. I can't afford to be offline for hours.

Is there any way to get the encryption software to sound an alarm so I know the phone is down?

Alternatively I'll need to remove encryption, which is a real pain as I need to do a system reset/

 

[belodion]

You don’t want to try to fix the rebooting?

 

[B. Diddy]

Welcome to Android Central! When you say the phone is dying, do you mean you're letting the battery drop to zero, or that it seems to unexpectedly power down on its own earlier than that?

If you're letting it drop to zero, then try not to -- that's bad for the battery's overall lifespan, and you'll notice significant deterioration in as little as 6 months or so. If it's unexpectedly powering down before that, then that could be a sign the battery's already failing, or it could mean a problem with the firmware or motherboard. Considering that the phone is very important for your business, I'd either reconsider your charging habits (i.e., bring a powerbank with you) or bring the phone to a repair shop to figure out why it's dying (if it's powering off prematurely).

 

[Ron MacRae]

No I don't want to spend time debugging the problem, I've no clue what that is, and no the battery is not empty. In fact it sometimes happens while the charger is on, while I'm asleep.
When the phone fails. I want it to restart. End of story.
Either by waking me so I can type in the pin or, even better, by not waiting for a pin.

 

[Mooncatt]

I agree with the others about trying to get to the root cause of the unexpected reboots. In the mean time, go into your phone's settings, then to the security settings. Look to see if you have anything related to startup. In my case, I have a "Secure startup" option that sets whether or not I need to enter my PIN after a reboot. That doesn't require a factory reset or anything like that.

 

[Rukbat]

No, there's no alarm for either the lock screen or encryption.

Does the phone "go offline" wen it's locked? If not, just lock it before putting it in your pocket.

If it does, try something like Proximity Service. That will keep the phone from locking while it's in your pocket (if the screen is facing your leg).

But if it still reboots randomly, there's nothing you can do for it except boot notification - the carrier tone you get when the phone boots. Fixing the reboot problem is probably your best solution.

 

[B. Diddy]

When the phone fails. I want it to restart. End of story.

I understand why you might not want to spend time figuring out the problem, but be aware that this might eventually lead to the phone failing completely, and possibly some time soon. If that happens and you didn't back up or sync your important data, it'll be gone. You already mentioned how important the phone is for work, so we felt this would be a worth mentioning.

The fact that this happens when the battery isn't empty increases the suspicion that the battery might be failing.

 

[Mooncatt]

The fact that this happens when the battery isn't empty increases the suspicion that the battery might be failing.

I would almost suspect this (would need some more info to be conclusive), but Ron also said this happened while plugged in and he was sleeping. So unless it was a defective cable or charger preventing a supply of power, I would almost rule out a battery problem. But again, he would have to do some leg work for us to help narrow it down more.

 

[B. Diddy]

Ah yes, good point. Almost more worrisome, though, since it might point towards a motherboard problem.

 

[Ron MacRae]

This is an intermittent problem. 3 or 4 times in the last 6 months. The reason it's a problem is that it caused me to miss a vital appointment because the alarm didn't go off as the phone was waiting for a pin. I don't know if it's a software or hardware issue. It always happens while the phone is locked, possibly because the phone spends 95% of it's time locked. The phone attempts to restart but can't because of the requirement for the encryption pin. The problem is that I don't know it's restarted and it stays down for several hours until I notice. As far as I can see the only solution to this problem is to remove encryption, which seems to require a hard reset. This seems to me to be bad design. I should have the option to be informed if the phone is looking for a pin.

 

[hallux]

The problem is that in order to access the "user" section of the phone the encryption needs to be unlocked, this requires the PIN. Until that is entered your personalizations and app data are inaccessible.

One popular troubleshooting step is to clear the cache partition. I don't see what device you have to provide direct guidance, generally you need to boot to recovery (however that's done for your device) and navigate to wipe the cache partition. Be careful, this is also a spot where you can wipe the device if you misstep.

 

[methodman89]

Is your phone rooted? Was it given to you by your employer with them setting it up?

 

[Mooncatt]

As far as I can see the only solution to this problem is to remove encryption, which seems to require a hard reset. This seems to me to be bad design. I should have the option to be informed if the phone is looking for a pin.

Did you try my suggestion in my initial reply (post #5 ) to check your security settings?

 

[Ron MacRae]

I can't find any option like "Secure startup". Anyway that's not what I want. I'd like my phone to stay secure, in case Iose it.
If it just started and locked immediately that would be fine, or if it made an alarm so I knew it was re-booting and wanted a password that would be fine too. It's the fact it sits quietly in an unusable state, in my pocket or on the bedside cabinet, for several hours that is the problem.
My phone is an HTC U11+, I bought it direct from HTC, I've not messed with it in any way, other than install a few Apps. While I'm a mainframe computer engineer by trade I'm not sufficiently clued up on the Android OS to want to do anything non-standard.
IMO this is bad program design. If the OS falls over and wants to restart it should. Having it properly restart is not a security exposure provided it stays locked. I'd like to report this to google as a design fault but can't find how to.

 

[hallux]

Hmm, Nougat changed the boot process such that entering the PIN was no longer required in order for core functions to work. I actually just tested, my Pixel 2 XL on Pie DOES receive phone calls after it's been rebooted but before the PIN has been entered. However - the ring is not my chosen ringtone and could be easily missed. This is called "direct boot", apparently this also allows alarms but if the alarm tone is in your secure storage it'll be some generic tone.

I wonder if this capability is selectable by the device manufacturer?

Here was the first link I found about this - https://www.androidauthority.com/community/threads/no-more-pre-or-in-built-encryption.30651/
Here's the AC article on this - https://www.androidcentral.com/android-70-what-direct-boot

 

[Ron MacRae]

Hallux, Thanks for the links but I I'm already on Android 8. The links talk about what happens once Android is fully booted but doesn't mention encryption, which I believe interrupts the boot process.

 

[hallux]

Actually, DirectBoot bypasses the need to unlock encryption for core apps to function, reread the links. It was specifically designed BECAUSE of encryption. You may not get caller ID or alarms (those would be in the encrypted user space) but you can still get calls with a very basic ringtone. As I noted - I tested this on my Pixel 2 XL (which IS encrypted).

 

[Ron MacRae]

Hallux, I tried that. I powered off my phone, powered it on, and left it at the encryption password screen. All calls go direct to voicemail. nothing on the phone.

 

[hallux]

Then maybe HTC isn't supporting that properly.

 

[Ron MacRae]

I've done a factory reset, which deleted all my apps & data, but I still get prompted for an encryption password at boot time. How do I get rid of encryption? Are there levels of reset?