diff --git a/docker/Dockerfile b/docker/Dockerfile
index 62a703a..e9d0b3f 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -8,5 +8,6 @@ RUN apk --no-cache add tini
 ENTRYPOINT ["/sbin/tini", "-g", "--"]
 CMD ["godns"]
 
+COPY etc/godns.conf /etc/godns.conf
 COPY godns /usr/local/bin/godns
 RUN chmod +x /usr/local/bin/godns
diff --git a/docker/Dockerfile.arm b/docker/Dockerfile.arm
index 901c304..9c4a359 100644
--- a/docker/Dockerfile.arm
+++ b/docker/Dockerfile.arm
@@ -10,5 +10,6 @@ RUN apk --no-cache add tini
 ENTRYPOINT ["/sbin/tini", "-g", "--"]
 CMD ["godns"]
 
+COPY etc/godns.conf /etc/godns.conf
 COPY godns-arm /usr/local/bin/godns
 RUN chmod +x /usr/local/bin/godns
diff --git a/docker/Dockerfile.arm64 b/docker/Dockerfile.arm64
index 64ff089..63cbe8e 100644
--- a/docker/Dockerfile.arm64
+++ b/docker/Dockerfile.arm64
@@ -10,5 +10,6 @@ RUN apk --no-cache add tini
 ENTRYPOINT ["/sbin/tini", "-g", "--"]
 CMD ["godns"]
 
+COPY etc/godns.conf /etc/godns.conf
 COPY godns-arm64 /usr/local/bin/godns
 RUN chmod +x /usr/local/bin/godns
diff --git a/etc/godns.conf b/etc/godns.conf
index 5bd363a..a94be7a 100644
--- a/etc/godns.conf
+++ b/etc/godns.conf
@@ -16,7 +16,6 @@ port = 53
 # Semicolon separate multiple files.
 server-list-file = "./etc/apple.china.conf;./etc/google.china.conf"
 resolv-file = "/etc/resolv.conf"
-dns-over-https = "https://cloudflare-dns.com/dns-query"
 timeout = 5  # 5 seconds
 # The concurrency interval request upstream recursive server
 # Match the PR15, https://github.com/kenshinx/godns/pull/15
diff --git a/hosts_redis.go b/hosts_redis.go
index 79c57f2..09edae9 100644
--- a/hosts_redis.go
+++ b/hosts_redis.go
@@ -48,7 +48,13 @@ func NewRedisProvider(rc *redis.Client, key string) HostProvider {
 					continue
 				}
 
+				rh.mu.RLock()
 				rh.hosts[recordName] = string(b)
+				rh.mu.RUnlock()
+			} else if msg.Channel == "godns:remove_record" {
+				rh.mu.RLock()
+				delete(rh.hosts, string(msg.Message))
+				rh.mu.RUnlock()
 			} else if msg.Channel == keyspaceEvent {
 				rh.Refresh()
 			}
diff --git a/resolver.go b/resolver.go
index b3a095f..1fbace8 100644
--- a/resolver.go
+++ b/resolver.go
@@ -36,8 +36,8 @@ type Resolver struct {
 	domain_server *suffixTreeNode
 	config        *ResolvSettings
 
-	tcpClient *dns.Client
-	udpClient *dns.Client
+	tcpClient   *dns.Client
+	udpClient   *dns.Client
 	httpsClient *dns.Client
 }
 
@@ -73,20 +73,20 @@ func NewResolver(c ResolvSettings) *Resolver {
 	timeout := r.Timeout()
 
 	r.udpClient = &dns.Client{
-		Net: "udp",
-		ReadTimeout: timeout,
+		Net:          "udp",
+		ReadTimeout:  timeout,
 		WriteTimeout: timeout,
 	}
 
 	r.tcpClient = &dns.Client{
-		Net: "tcp",
-		ReadTimeout: timeout,
+		Net:          "tcp",
+		ReadTimeout:  timeout,
 		WriteTimeout: timeout,
 	}
 
 	r.httpsClient = &dns.Client{
-		Net: "https",
-		ReadTimeout: timeout,
+		Net:          "https",
+		ReadTimeout:  timeout,
 		WriteTimeout: timeout,
 	}
 
@@ -250,8 +250,8 @@ func (r *Resolver) resolverFor(net, nameserver string) (*dns.Client, error) {
 	} else if strings.HasSuffix(nameserver, ":853") {
 		// TODO We need to set the server name so we can confirm the TLS connection. This may require a rewrite of storing nameservers.
 		return &dns.Client{
-			Net: "tcp-tls",
-			ReadTimeout: r.Timeout(),
+			Net:          "tcp-tls",
+			ReadTimeout:  r.Timeout(),
 			WriteTimeout: r.Timeout(),
 			TLSConfig: &tls.Config{
 				ServerName: "",
diff --git a/server.go b/server.go
index 4b8fab0..18f54a2 100644
--- a/server.go
+++ b/server.go
@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/miekg/dns"
+	"os"
 )
 
 type Server struct {
@@ -16,42 +17,48 @@ type Server struct {
 }
 
 func (s *Server) Addr() string {
+	if addr := os.Getenv("SERVER_BIND"); addr != "" {
+		return addr
+	}
+
 	return net.JoinHostPort(s.host, strconv.Itoa(s.port))
 }
 
 func (s *Server) Run() {
-	Handler := NewHandler()
+	handler := NewHandler()
 
 	tcpHandler := dns.NewServeMux()
-	tcpHandler.HandleFunc(".", Handler.DoTCP)
+	tcpHandler.HandleFunc(".", handler.DoTCP)
 
 	udpHandler := dns.NewServeMux()
-	udpHandler.HandleFunc(".", Handler.DoUDP)
+	udpHandler.HandleFunc(".", handler.DoUDP)
 
-	tcpServer := &dns.Server{Addr: s.Addr(),
-		Net:          "tcp",
-		Handler:      tcpHandler,
-		ReadTimeout:  s.rTimeout,
-		WriteTimeout: s.wTimeout}
+	tcpServer := &dns.Server{
+		Addr: s.Addr(),
+		Net: "tcp",
+		Handler: tcpHandler,
+		ReadTimeout: s.rTimeout,
+		WriteTimeout: s.wTimeout,
+	}
 
-	udpServer := &dns.Server{Addr: s.Addr(),
-		Net:          "udp",
-		Handler:      udpHandler,
-		UDPSize:      65535,
-		ReadTimeout:  s.rTimeout,
-		WriteTimeout: s.wTimeout}
+	udpServer := &dns.Server{
+		Addr: s.Addr(),
+		Net: "udp",
+		Handler: udpHandler,
+		UDPSize: 65535,
+		ReadTimeout: s.rTimeout,
+		WriteTimeout: s.wTimeout,
+	}
 
 	go s.start(udpServer)
 	go s.start(tcpServer)
-
 }
 
 func (s *Server) start(ds *dns.Server) {
-
 	logger.Info("Start %s listener on %s", ds.Net, s.Addr())
+
 	err := ds.ListenAndServe()
 	if err != nil {
 		logger.Error("Start %s listener on %s failed:%s", ds.Net, s.Addr(), err.Error())
 	}
-
 }
diff --git a/settings.go b/settings.go
index dc4a2e5..dc5a673 100644
--- a/settings.go
+++ b/settings.go
@@ -7,6 +7,7 @@ import (
 	"strconv"
 
 	"github.com/BurntSushi/toml"
+	"strings"
 )
 
 var (
@@ -59,6 +60,10 @@ type MemcacheSettings struct {
 }
 
 func (s RedisSettings) Addr() string {
+	if addr := os.Getenv("REDIS_ADDR"); addr != "" {
+		return addr
+	}
+
 	return s.Host + ":" + strconv.Itoa(s.Port)
 }
 
@@ -92,10 +97,9 @@ type HostsSettings struct {
 }
 
 func init() {
-
 	var configFile string
 
-	flag.StringVar(&configFile, "c", "./etc/godns.conf", "Look for godns toml-formatting config file in this directory")
+	flag.StringVar(&configFile, "c", "/etc/godns.conf", "Look for godns toml-formatting config file in this directory")
 	flag.Parse()
 
 	if _, err := toml.DecodeFile(configFile, &settings); err != nil {
@@ -104,4 +108,12 @@ func init() {
 		os.Exit(1)
 	}
 
+	// Env overrides
+	if cacheBackend := os.Getenv("CACHE_BACKEND"); cacheBackend != "" {
+		settings.Cache.Backend = cacheBackend
+	}
+
+	if memcacheServers := os.Getenv("MEMCACHE_SERVERS"); memcacheServers != "" {
+		settings.Memcache.Servers = strings.Split(memcacheServers, ",")
+	}
 }