How to edit /etc/hosts file in Android Studio emulator running in nougat?

Anyone know how to edit /etc/hosts file inside an android studio emulator running in nougat? I will be editing it so I can use my virtual host in my local web server. I tried editing it through terminal using adb however, it is returning Read-only file system. Tried also using chmod but still it fails.

Update: I also tried pulling and pushing files using adb $ ./adb -s emulator-5554 push ~/Desktop/hosts /system/etc/hosts

adb: error: failed to copy '/Users/Christian/Desktop/hosts' to '/system/etc/hosts': couldn't create file: Read-only file system


Solution 1:

1) android-sdk-macosx/tools/emulator -avd <avdname> -writable-system
2) ./adb root
3) ./adb remount
4) ./adb push <local>/hosts /etc/hosts

Android file host can be

/etc/hosts <--- This worked for me
/etc/system/hosts
/system/etc/hosts

Check

1) ./adb shell
2) cat /etc/hosts
3) ping customsite.com

Solution 2:

Step by Step

  1. Don’t Create the AVD with a Google Play image.
  2. Use for example Google APIs Intel x86 Atom System Image.
  3. Start the emulator with the following command…

    emulator.exe –avd <avd name> -writable-system
    

For example:

    C:\Users\ilyas.mamun\AppData\Local\Android\Sdk\emulator>emulator.exe -avd Pixel_API_25 -writable-system

    emulator: WARNING: System image is writable
    HAX is working and emulator runs in fast virt mode.
    audio: Failed to create voice `goldfish_audio_in'
    qemu-system-i386.exe: warning: opening audio input failed
    audio: Failed to create voice `adc'
  1. Root and Remount the AVD like the followings…

    C:\Users\ilyas.mamun\AppData\Local\Android\Sdk\platform-tools>adb root
    
    C:\Users\ilyas.mamun\AppData\Local\Android\Sdk\platform-tools>adb remount
    remount succeeded
    
    C:\Users\ilyas.mamun\AppData\Local\Android\Sdk\platform-tools>adb shell
    eneric_x86:/ # cd system
    generic_x86:/system # cd etc
    generic_x86:/system/etc # cat hosts
    127.0.0.1       localhost
    ::1             ip6-localhost
    
    generic_x86:/system/etc # echo "192.168.1.120   ilyasmamun.blogspot.com" >> hosts
    generic_x86:/system/etc # cat hosts
    
    127.0.0.1       localhost
    ::1             ip6-localhost
    192.168.1.120     ilyasmamun.blogspot.com
    generic_x86:/system/etc #
    

Solution 3:

Here is how i was able to do it working on OSX. After reading a bunch of different instruction nothing seemd to work for me untill someone mentioned that you have a very narrow window for copying the file from your disk to the emulated device or it becomes read-only again

  1. Start your emulator.
  2. In your terminal find the folder "platform-tools" for your devices
  3. Prepare the hosts file you want to copy to your device (in my case i put it on desktop)
  4. String together a bunch of commands to copy the file quickly. This is what worked for me ./adb root && ./adb -s emulator-5554 remount && ./adb -s emulator-5554 push ~/Desktop/hosts /system/etc/hosts 'emulator-5554' is the name of my device which you can find by typing ./adb devices

after that the terminal responded with

restarting adbd as root remount succeeded [100%] /system/etc/hosts

you can veryfy the copy was successfull by ./adb shell and then cat /system/etc/hosts

I was then able to connect to my virtual hosts from the emulated device

Just to be complete here is how my hosts file looked like 10.0.2.2 my-virtual-host

I hope this helps someone as i spet quite some time trying to figure this out.

Solution 4:

I was able to edit the /etc/hosts file by launching the emulator with -writable-system and remounting the emulator using adb remount. After that the hosts file inside the emulator is editable. I tried pushing/replacing the file and succeeded.

Solution 5:

Below are the steps I followed on my Windows machine on Windows Terminal: Run the following command to know your AVDs:

emulator -list-avds

enter image description here

Run the following command to open the emulator for writable mode:

emulator -avd Pixel_XL_API_29 -writable-system -no-snapshot-load

Replace Pixel_XL_API_29 with your AVD name.

enter image description here

Ignore the warnings there.

In a new Terminal tab run the following commands:

  • adb root
  • adb shell avbctl disable-verification
  • adb reboot

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Wait for your emulator to reboot. It can take upto 1 minute.

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When the emulator is rebooted, run the following commands:

  • adb root
  • adb remount

You will get a remount succeeded message after that:

enter image description here

Now is the time to push our host file from Windows machine to Android's emulator

adb push D:\hosts /system/etc/

D:\hosts is the location of the hosts file present at the D drive of my Windows machine. /system/etc/ is the location in Android's emulator where we want to copy that file.

After successfull operation you will see a message like this: enter image description here

To verify that the hosts file has been pushed you can run the following commands:

  • adb shell
  • cd system
  • cd etc
  • cat hosts

You will see the contents of hosts file in the Terminal:

enter image description here