CustomNetworkModule.java

package com.yourapp;

import com.facebook.react.modules.network.OkHttpClientFactory;
import com.facebook.react.modules.network.ReactCookieJarContainer;

import okhttp3.OkHttpClient;

public class CustomNetworkModule implements OkHttpClientFactory {
    @Override
    public OkHttpClient createNewNetworkModuleClient() {
        return new OkHttpClient.Builder()
                .dns(new CustomDNS())
                .cookieJar(new ReactCookieJarContainer())
                .build();
    }
}