Copy entire phone to the same device? I bought second Asus ZS570KL as backup phone since my old one starts to do... weird things. I created full backup using:

./adb backup -apk -all -obb -shared -v -f /backups/phone8.ab


And later performed 

./adb restore /backups/phone8.ab


But it only restored files. When I checked out adb logcat -b system I noticed:

04-06 22:29:45.596 10100 10256 W DefContainer: Failed to parse package at /data/cache/backup_stage/pl.m4x.sphinx_customer_android_mobile_app_v2: android.content.pm.PackageParser$PackageParserException: Failed to parse /data/cache/backup_stage/pl.m4x.sphinx_customer_android_mobile_app_v2
04-06 22:29:45.617  2214 10078 D BackupManagerService: [discarding file content]
04-06 22:29:45.624  2214 10078 I chatty  : uid=1000(system) adb-restore identical 52 lines
04-06 22:29:45.624  2214 10078 D BackupManagerService: [discarding file content]
04-06 22:29:45.625  2214 10078 I BackupManagerService: Package pl.neptis.yanosik.mobi.android not installed; requiring apk in dataset
04-06 22:29:45.625  2214 10078 D BackupManagerService: APK file; installing
04-06 22:29:45.625  2214 10078 D BackupManagerService: Installing from backup: pl.neptis.yanosik.mobi.android
04-06 22:29:49.671 10100 10256 W DefContainer: Failed to parse package at /data/cache/backup_stage/pl.neptis.yanosik.mobi.android: android.content.pm.PackageParser$PackageParserException: Failed to parse /data/cache/backup_stage/pl.neptis.yanosik.mobi.android
04-06 22:29:49.699  2214 10078 D BackupManagerService: [discarding file content]
04-06 22:29:49.805  2214 10078 I chatty  : uid=1000(system) adb-restore identical 100 lines
04-06 22:29:49.805  2214 10078 D BackupManagerService: [discarding file content]
04-06 22:29:49.805  2214 10078 I BackupManagerService: Package ru.dront78.pulsedroid not installed; requiring apk in dataset
04-06 22:29:49.805  2214 10078 D BackupManagerService: APK file; installing
04-06 22:29:49.805  2214 10078 D BackupManagerService: Installing from backup: ru.dront78.pulsedroid
04-06 22:29:49.811 10100 10256 W DefContainer: Failed to parse package at /data/cache/backup_stage/ru.dront78.pulsedroid: android.content.pm.PackageParser$PackageParserException: Failed to parse /data/cache/backup_stage/ru.dront78.pulsedroid
04-06 22:29:49.812  2214 10078 I BackupManagerService: Package ru.zdevs.zarchiver not installed; requiring apk in dataset
04-06 22:29:49.813  2214 10078 D BackupManagerService: APK file; installing
04-06 22:29:49.813  2214 10078 D BackupManagerService: Installing from backup: ru.zdevs.zarchiver
04-06 22:29:50.296 10100 10256 W DefContainer: Failed to parse package at /data/cache/backup_stage/ru.zdevs.zarchiver: android.content.pm.PackageParser$PackageParserException: Failed to parse /data/cache/backup_stage/ru.zdevs.zarchiver
04-06 22:29:50.304  2214 10078 D BackupManagerService: [discarding file content]
04-06 22:29:50.305  2214 10078 I BackupManagerService: Package simple.hexadecimal.color not installed; requiring apk in dataset
04-06 22:29:50.305  2214 10078 D BackupManagerService: APK file; installing
04-06 22:29:50.305  2214 10078 D BackupManagerService: Installing from backup: simple.hexadecimal.color
04-06 22:29:50.470 10100 10256 W DefContainer: Failed to parse package at /data/cache/backup_stage/simple.hexadecimal.color: android.content.pm.PackageParser$PackageParserException: Failed to parse /data/cache/backup_stage/simple.hexadecimal.color
04-06 22:29:50.473  2214 10078 D BackupManagerService: [discarding file content]


So it seems to crash. Google backup only seems to back up 80 of my 380 apps and definitely doesn't back up largest ones. What are my other options to perform full device mirror including all apps data, settings, credentials and everything? I'd like to have exactly mirrored 2 devices.
To manage the system and not give it root access, you neex to use a custom recovery.

A custom recovery will allow you to backup your DATA &amp; SYSTEM Partitions so thst you can restore everything easily and safely.

The most common custom recovery in my opinion is TWRP or Team Win Recovery Project, this would be the newest most common in succession from Clock Work Mod as the most common.

I searched for TWRP for your device, and i got this installation guide... . 
Zenfone 3 &amp; 3 Delux TWRP

Once you've successfully flashed TWRP you can do the device clone that you want by going to Backup and performing a full device backup to the External SD Card.

Now install TWRP on Device 2.

Place your SD Card from Device 1 with the new backup into Device 2   

Boot into TWRP on Device 2 

Go to Restore and select External SD  

Select your backup

Restore the backup.

The second device will be entirely replaced with the data from the first device excluding some stuff like IMEI number etc, depending on your TWRP Version....



Locked Bootloader ?

Asus provides an Official unlock tool for your specific device at the Asus website...

Here's a direct link... 


  Asus Unlock Tool


Reference ;
www.asus.com/Phone/ZenFone-3....