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Last active April 17, 2024 03:40
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Set the NTP server of your android device
tags
Android
Android Things

Set the NTP server of your android device

Just use this command to set a server address to automatically sync your device time. ( ͡° ͜ʖ ͡°)✧

$ adb shell settings put global ntp_server <new-ntp-server>

Background

I have a Raspberry Pi 3 with Android Things installed on it. But the time is never synchronized...

After googling it, I found this piece of code in NtpTrustedTime.java

public class NtpTrustedTime implements TrustedTime {
    ...
    public static synchronized NtpTrustedTime getInstance(Context context) {
        if (sSingleton == null) {
            final Resources res = context.getResources();
            final ContentResolver resolver = context.getContentResolver();
            final String defaultServer = res.getString(
                    com.android.internal.R.string.config_ntpServer);
            final long defaultTimeout = res.getInteger(
                    com.android.internal.R.integer.config_ntpTimeout);
            final String secureServer = Settings.Global.getString(
                    resolver, Settings.Global.NTP_SERVER);
            final long timeout = Settings.Global.getLong(
                    resolver, Settings.Global.NTP_TIMEOUT, defaultTimeout);
            final String server = secureServer != null ? secureServer : defaultServer;
            sSingleton = new NtpTrustedTime(server, timeout);
            sContext = context;
        }
        return sSingleton;
    }
}

It shows that android tring to get NTP server from:

  1. Settings.Global.NTP_SERVER first

  2. Then com.android.internal.R.string.config_ntpServer

And the NTP server of my Android Things is time.android.com, that's why it dose not work (I'm in China...).


Fortunately, it is easy to set settings via adb:

$ adb shell settings put global ntp_server asia.pool.ntp.org

# test
$ adb shell settings get global ntp_server 
> asia.pool.ntp.org

🎉 CHEERS

@ipcjs
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ipcjs commented Dec 1, 2022

time.windows.com is a good choice in China.

@don-dolarson
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don-dolarson commented May 26, 2023

Thank you for this thread.

There is no existing ntp_server setting in LineageOS 20 but can easily be created just by pushing the "put global ntp_server domain" command through adb.

Setting is preserved between reboots and my router logs can confirm that NTP address changed from time.android.com to the chosen NTP server. GPS automatically connects to time.xtracloud.net (Cloudflare) in this ROM.

@wodeguaiguai
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wodeguaiguai commented Jul 21, 2023

Failed to execute this command, my devices is android 12 colorOS, it seems no write permisson

➜ /Users/guaio >adb shell settings put global ntp_server ntp.aliyun.com

Exception occurred while executing 'put':
java.lang.SecurityException: Permission denial: writing to settings requires:android.permission.WRITE_SECURE_SETTINGS
	at com.android.providers.settings.SettingsProvider.enforceWritePermission(SettingsProvider.java:2640)
	at com.android.providers.settings.SettingsProvider.mutateGlobalSetting(SettingsProvider.java:1632)
	at com.android.providers.settings.SettingsProvider.insertGlobalSetting(SettingsProvider.java:1586)
	at com.android.providers.settings.SettingsProvider.call(SettingsProvider.java:588)
	at android.content.ContentProvider.call(ContentProvider.java:2473)
	at android.content.ContentProvider$Transport.call(ContentProvider.java:521)
	at com.android.providers.settings.SettingsService$MyShellCommand.putForUser(SettingsService.java:382)
	at com.android.providers.settings.SettingsService$MyShellCommand.onCommand(SettingsService.java:278)
	at com.android.modules.utils.BasicShellCommandHandler.exec(BasicShellCommandHandler.java:97)
	at android.os.ShellCommand.exec(ShellCommand.java:38)
	at com.android.providers.settings.SettingsService.onShellCommand(SettingsService.java:50)
	at android.os.Binder.shellCommand(Binder.java:970)
	at android.os.Binder.onTransact(Binder.java:854)
	at android.os.Binder.execTransactInternal(Binder.java:1226)
	at android.os.Binder.execTransact(Binder.java:1163)

@qianbinbin
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Thanks for the information. I've tried several servers, cn.ntp.org.cn is the fastest one in China.

@albertopasqualetto
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In my device if I first of all do adb shell settings get global ntp_server, it returns null.

@costaht
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costaht commented Jan 10, 2024

For those trying to connect to your TV, I used adb connect 192.168.1.65:5555 to connect to my tv via LAN. Once you run that command you're gonna have to click Accept on the pop-up that is shown on your tv screen.
adb devices should show your TV as active, then you can run the commands above.

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