Merge pull request #16347 from jfrazelle/revert-ulp

Revert "Make daemon to start with no userlandproxy by default"

daemon/config_unix.go

@@ -74,7 +74,7 @@ func (config *Config) InstallFlags(cmd *flag.FlagSet, usageFn func(string) strin
 	cmd.Var(opts.NewIPOpt(&config.Bridge.DefaultGatewayIPv6, ""), []string{"-default-gateway-v6"}, usageFn("Container default gateway IPv6 address"))
 	cmd.BoolVar(&config.Bridge.InterContainerCommunication, []string{"#icc", "-icc"}, true, usageFn("Enable inter-container communication"))
 	cmd.Var(opts.NewIPOpt(&config.Bridge.DefaultIP, "0.0.0.0"), []string{"#ip", "-ip"}, usageFn("Default IP when binding container ports"))
-	cmd.BoolVar(&config.Bridge.EnableUserlandProxy, []string{"-userland-proxy"}, false, usageFn("Use userland proxy for loopback traffic"))
+	cmd.BoolVar(&config.Bridge.EnableUserlandProxy, []string{"-userland-proxy"}, true, usageFn("Use userland proxy for loopback traffic"))
 	cmd.BoolVar(&config.EnableCors, []string{"#api-enable-cors", "#-api-enable-cors"}, false, usageFn("Enable CORS headers in the remote API, this is deprecated by --api-cors-header"))
 	cmd.StringVar(&config.CorsHeaders, []string{"-api-cors-header"}, "", usageFn("Set CORS headers in the remote API"))
 

docs/articles/networking.md

@@ -471,7 +471,7 @@ editing this setting.
 > container. In such conflicting situation, Docker created iptables rules will
 > take precedence and route to the container.
 
-The `--userland-proxy` parameter, false by default, provides a userland
+The `--userland-proxy` parameter, true by default, provides a userland
 implementation for inter-container and outside-to-container communication. When
 disabled, Docker uses both an additional `MASQUERADE` iptable rule and the
 `net.ipv4.route_localnet` kernel parameter which allow the host machine to

docs/reference/commandline/daemon.md

@@ -56,7 +56,7 @@ weight=1
       --tlscert="~/.docker/cert.pem"         Path to TLS certificate file
       --tlskey="~/.docker/key.pem"           Path to TLS key file
       --tlsverify=false                      Use TLS and verify the remote
-      --userland-proxy=false                  Use userland proxy for loopback traffic
+      --userland-proxy=true                  Use userland proxy for loopback traffic
 
 Options with [] may be specified multiple times.
 

hack/make/.integration-daemon-start

@@ -14,7 +14,7 @@ exec 41>&1 42>&2
 
 export DOCKER_GRAPHDRIVER=${DOCKER_GRAPHDRIVER:-vfs}
 export DOCKER_EXECDRIVER=${DOCKER_EXECDRIVER:-native}
-export DOCKER_USERLANDPROXY=${DOCKER_USERLANDPROXY:-false}
+export DOCKER_USERLANDPROXY=${DOCKER_USERLANDPROXY:-true}
 
 # example usage: DOCKER_STORAGE_OPTS="dm.basesize=20G,dm.loopdatasize=200G"
 storage_params=""

integration-cli/docker_cli_daemon_test.go

@@ -860,6 +860,7 @@ func (s *DockerDaemonSuite) TestDaemonIP(c *check.C) {
 	out, err := d.Cmd("run", "-d", "-p", "8000:8000", "busybox", "top")
 	c.Assert(err, check.NotNil,
 		check.Commentf("Running a container must fail with an invalid --ip option"))
+	c.Assert(strings.Contains(out, "Error starting userland proxy"), check.Equals, true)
 
 	ifName := "dummy"
 	out, err = createInterface(c, "dummy", ifName, ipStr)

integration-cli/docker_utils.go

@@ -69,7 +69,7 @@ func NewDaemon(c *check.C) *Daemon {
 		c.Fatalf("Could not create %s/graph directory", daemonFolder)
 	}
 
-	userlandProxy := false
+	userlandProxy := true
 	if env := os.Getenv("DOCKER_USERLANDPROXY"); env != "" {
 		if val, err := strconv.ParseBool(env); err != nil {
 			userlandProxy = val

man/docker.1.md

@@ -162,7 +162,7 @@ unix://[/path/to/socket] to use.
   Default is false.
 
 **--userland-proxy**=*true*|*false*
-    Rely on a userland proxy implementation for inter-container and outside-to-container loopback communications. Default is false.
+    Rely on a userland proxy implementation for inter-container and outside-to-container loopback communications. Default is true.
 
 **-v**, **--version**=*true*|*false*
   Print version information and quit. Default is false.