Could not connect to React Native development server on Android

Question

When I run react-native run-android, it gives me the following error:

Could not connect to development server

Answer 1

Starting with Android 9.0 (API level 28), cleartext support is disabled by default. we can use android:usesCleartextTraffic="true" this will work but this is not recommended solution. For Permanent and recommended Solution is below:

Step 1 : create a file in android folder app/src/debug/res/xml/network_security_config.xml

Step 2 : add this to network_security_config.xml

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
  <!-- deny cleartext traffic for React Native packager ips in release -->
  <domain-config cleartextTrafficPermitted="true">
   <domain includeSubdomains="true">localhost</domain>
   <domain includeSubdomains="true">10.0.2.2</domain>
   <domain includeSubdomains="true">10.0.3.2</domain>
  </domain-config>
</network-security-config>

Step 3 : Apply the config to your AndroidManifest.xml

<application
 android:networkSecurityConfig="@xml/network_security_config">
</application>

Answer 2

Make sure NPM server is running. Else run it again. It will solve the issue.

Answer 3

For me i have uninstalled a package that i recently installed and the project ran again on my physical device using the following command "npm uninstall recentPackageName" hope this helps :)

Answer 4

In my case, running on a Macbook, i had to turn off my firewall, thus allowing incoming connections from my android. RN v0.61.5

Answer 5

We faced this issue, In order to fix this, solution is dead simple is below.

1. Cancel the current process of“react-native run-android” by CTRL + C or CMD + C
2. Close metro bundler window command line which opened automatically.
3. Run the command again, “react-native run-android”.

Basically this error tells that your current build got failed due to reasons like Code issue or dependency issue.

Click here for more details

Answer 6

Found the issue with Android X device.

For Android API 28 and above

In network_security_config.xml with cleartextTrafficPermitted="true"

<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
  <domain-config cleartextTrafficPermitted="true">
    ....
  </domain-config>
</network-security-config>

Then, reload JS