How do you get the current DNS servers for Android?

Question

I\'m trying to get hold of the addresses to the currently used DNS servers in my application, either I\'m connected thru Wifi or mobile. The DhcpInfo object should provide t

Answer 1

I recommend dnsjava for complex DNS use on Android. Let's see how dnsjava determines the current active DNS server for the connection. From dnsjava ResolverConfig.java:428:

/**
 * Parses the output of getprop, which is the only way to get DNS
 * info on Android. getprop might disappear in future releases, so
 * this code comes with a use-by date.
 */
private void
findAndroid() {
    // This originally looked for all lines containing .dns; but
    // http://code.google.com/p/android/issues/detail?id=2207#c73
    // indicates that net.dns* should always be the active nameservers, so
    // we use those.
    String re1 = "^\\d+(\\.\\d+){3}$";
    String re2 = "^[0-9a-f]+(:[0-9a-f]*)+:[0-9a-f]+$";
    try { 
        ArrayList lserver = new ArrayList(); 
        ArrayList lsearch = new ArrayList(); 
        String line; 
        Process p = Runtime.getRuntime().exec("getprop"); 
        InputStream in = p.getInputStream();
        InputStreamReader isr = new InputStreamReader(in);
        BufferedReader br = new BufferedReader(isr);
        while ((line = br.readLine()) != null ) { 
            StringTokenizer t = new StringTokenizer(line, ":");
            String name = t.nextToken();
            if (name.indexOf( "net.dns" ) > -1) {
                String v = t.nextToken();
                v = v.replaceAll("[ \\[\\]]", "");
                if ((v.matches(re1) || v.matches(re2)) &&
                    !lserver.contains(v))
                    lserver.add(v);
            }
        }
        configureFromLists(lserver, lsearch);
    } catch ( Exception e ) { 
        // ignore resolutely
    }
}