diff --git a/src/bin/local.rs b/src/bin/local.rs
index 25e11a01..9a4734db 100644
--- a/src/bin/local.rs
+++ b/src/bin/local.rs
@@ -151,7 +151,7 @@ fn main() {
         app = clap_app!(@app (app)
             (@arg LOCAL_DNS_ADDR: --("local-dns-addr") +takes_value required_if("PROTOCOL", "dns") {validator::validate_local_dns_addr} "Specify the address of local DNS server, send queries directly")
             (@arg REMOTE_DNS_ADDR: --("remote-dns-addr") +takes_value required_if("PROTOCOL", "dns") {validator::validate_address} "Specify the address of remote DNS server, send queries through shadowsocks' tunnel")
-            (@arg DNS_LOCAL_ADDR: --("dns-addr") +takes_value {validator::validate_server_addr} "DNS address, listen to this address if specified")
+            (@arg DNS_LOCAL_ADDR: --("dns-addr") +takes_value requires_all(&["LOCAL_DNS_ADDR", "REMOTE_DNS_ADDR"]) {validator::validate_server_addr} "DNS address, listen to this address if specified")
         );
     }
 
diff --git a/src/config.rs b/src/config.rs
index 47a82060..781c48fe 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1640,17 +1640,7 @@ impl Config {
     /// Check if DNS Relay is enabled
     #[cfg(feature = "local-dns")]
     pub(crate) fn is_local_dns_relay(&self) -> bool {
-        if self.config_type == ConfigType::DnsLocal || self.local_dns_addr.is_some() {
-            return true;
-        }
-
-        cfg_if! {
-            if #[cfg(target_os = "android")] {
-                self.local_dns_path.is_some()
-            } else {
-                false
-            }
-        }
+        self.config_type == ConfigType::DnsLocal || self.dns_bind_addr.is_some()
     }
 }
 
diff --git a/src/relay/dnsrelay/mod.rs b/src/relay/dnsrelay/mod.rs
index 1dbe3707..4a05754c 100644
--- a/src/relay/dnsrelay/mod.rs
+++ b/src/relay/dnsrelay/mod.rs
@@ -194,6 +194,7 @@ impl<Remote: upstream::Upstream> DnsRelay<Remote> {
         let acl = self.context.acl();
         let local = self.context.local_dns();
         let remote = &self.remote_upstream;
+
         // Start querying name servers
         debug!(
             "attempting lookup of {:?} {} with ns {:?} and {:?}",
@@ -355,14 +356,14 @@ async fn run_udp<Remote: upstream::Upstream + Send + Sync + 'static>(
             }
         };
 
-        debug!("received src: {}, query: {:?}", src, request);
+        trace!("DNS query from {}, {:?}", src, request);
 
         let relay = relay.clone();
         let tx = tx.clone();
 
         tokio::spawn(async move {
             let message = relay.resolve(request).await;
-            debug!("DNS src: {}, final response: {:?}", src, message);
+            trace!("DNS response to {}, {:?}", src, message);
 
             match message.to_vec() {
                 Err(err) => {