chore(dns)!: remove DNS server

Signed-off-by: Charly Molter <charly.molter@konghq.com> chore(dns): remove global DNS view Now that we don't run the DNS server we don't need to have vips not overlapping between mesh. This removes this feature which greatly improves scalability when using multi-mesh Signed-off-by: Charly Molter <charly.molter@konghq.com> Fix chnages Signed-off-by: Charly Molter <charly.molter@konghq.com>
kumahq · Apr 26, 2022 · e047ece · e047ece
1 parent 3f0433c
commit e047ece
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Showing 29 changed files with 165 additions and 1,228 deletions.
diff --git a/UPGRADE.md b/UPGRADE.md
@@ -8,6 +8,8 @@ does not have any particular instructions.
 
 ## Upcoming release
 
+The `control-plane` no longer hosts a builtin DNS server. You should always rely on the embedded DNS in the dataplane proxy and VIPs can't be used without transparent proxy.
+
 ## Upgrade to `1.6.x`
 
 ### Helm

diff --git a/app/kuma-cp/cmd/run.go b/app/kuma-cp/cmd/run.go
@@ -14,7 +14,6 @@ import (
 	"github.com/kumahq/kuma/pkg/core/bootstrap"
 	"github.com/kumahq/kuma/pkg/defaults"
 	"github.com/kumahq/kuma/pkg/diagnostics"
-	"github.com/kumahq/kuma/pkg/dns"
 	dp_server "github.com/kumahq/kuma/pkg/dp-server"
 	"github.com/kumahq/kuma/pkg/gc"
 	"github.com/kumahq/kuma/pkg/hds"
@@ -88,10 +87,6 @@ func newRunCmdWithOpts(opts kuma_cmd.RunCmdOpts) *cobra.Command {
 				runLog.Error(err, "unable to set up Monitoring Assignment server")
 				return err
 			}
-			if err := dns.Setup(rt); err != nil {
-				runLog.Error(err, "unable to set up DNS")
-				return err
-			}
 			if err := xds.Setup(rt); err != nil {
 				runLog.Error(err, "unable to set up XDS")
 				return err

diff --git a/pkg/api-server/config_ws_test.go b/pkg/api-server/config_ws_test.go
@@ -98,7 +98,6 @@ var _ = Describe("Config WS", func() {
 		  "dnsServer": {
 			"CIDR": "240.0.0.0/4",
 			"domain": "mesh",
-			"port": 5653,
 			"serviceVipEnabled": true
 		  },
 		  "dpServer": {

diff --git a/pkg/config/dns-server/config.go b/pkg/config/dns-server/config.go
@@ -11,8 +11,6 @@ import (
 type DNSServerConfig struct {
 	// The domain that the server will resolve the services for
 	Domain string `yaml:"domain" envconfig:"kuma_dns_server_domain"`
-	// Port on which the server is exposed
-	Port uint32 `yaml:"port" envconfig:"kuma_dns_server_port"`
 	// CIDR used to allocate virtual IPs from
 	CIDR string `yaml:"CIDR" envconfig:"kuma_dns_server_cidr"`
 	// ServiceVipEnabled will create a service "<kuma.io/service>.mesh" dns entry for every service.
@@ -23,9 +21,6 @@ func (g *DNSServerConfig) Sanitize() {
 }
 
 func (g *DNSServerConfig) Validate() error {
-	if g.Port > 65535 {
-		return errors.New("Port must be in the range [0, 65535]")
-	}
 	_, _, err := net.ParseCIDR(g.CIDR)
 	if err != nil {
 		return errors.New("Must provide a valid CIDR")
@@ -39,7 +34,6 @@ func DefaultDNSServerConfig() *DNSServerConfig {
 	return &DNSServerConfig{
 		ServiceVipEnabled: true,
 		Domain:            "mesh",
-		Port:              5653,
 		CIDR:              "240.0.0.0/4",
 	}
 }
diff --git a/pkg/config/loader_test.go b/pkg/config/loader_test.go
@@ -210,7 +210,6 @@ var _ = Describe("Config loader", func() {
 			Expect(cfg.Diagnostics.DebugEndpoints).To(BeTrue())
 
 			Expect(cfg.DNSServer.Domain).To(Equal("test-domain"))
-			Expect(cfg.DNSServer.Port).To(Equal(uint32(15653)))
 			Expect(cfg.DNSServer.CIDR).To(Equal("127.1.0.0/16"))
 			Expect(cfg.DNSServer.ServiceVipEnabled).To(BeFalse())
 
@@ -411,7 +410,6 @@ multizone:
       maxMsgSize: 2
 dnsServer:
   domain: test-domain
-  port: 15653
   CIDR: 127.1.0.0/16
   serviceVipEnabled: false
 defaults:
@@ -568,7 +566,6 @@ experimental:
 				"KUMA_API_SERVER_CORS_ALLOWED_DOMAINS":                                                     "https://kuma,https://someapi",
 				"KUMA_GUI_SERVER_API_SERVER_URL":                                                           "http://localhost:1234",
 				"KUMA_DNS_SERVER_DOMAIN":                                                                   "test-domain",
-				"KUMA_DNS_SERVER_PORT":                                                                     "15653",
 				"KUMA_DNS_SERVER_CIDR":                                                                     "127.1.0.0/16",
 				"KUMA_DNS_SERVER_SERVICE_VIP_ENABLED":                                                      "false",
 				"KUMA_MODE":                                                                                "zone",

diff --git a/pkg/core/bootstrap/bootstrap.go b/pkg/core/bootstrap/bootstrap.go
@@ -36,7 +36,6 @@ import (
 	runtime_reports "github.com/kumahq/kuma/pkg/core/runtime/reports"
 	secret_cipher "github.com/kumahq/kuma/pkg/core/secrets/cipher"
 	secret_manager "github.com/kumahq/kuma/pkg/core/secrets/manager"
-	"github.com/kumahq/kuma/pkg/dns/resolver"
 	"github.com/kumahq/kuma/pkg/dp-server/server"
 	"github.com/kumahq/kuma/pkg/envoy/admin"
 	"github.com/kumahq/kuma/pkg/envoy/admin/access"
@@ -83,7 +82,6 @@ func buildRuntime(appCtx context.Context, cfg kuma_cp.Config) (core_runtime.Runt
 	}))
 
 	initializeConfigManager(builder)
-	initializeDNSResolver(cfg, builder)
 
 	builder.WithResourceValidators(core_runtime.ResourceValidators{
 		Dataplane: dataplane.NewMembershipValidator(),
@@ -445,10 +443,6 @@ func initializeResourceManager(cfg kuma_cp.Config, builder *core_runtime.Builder
 	return nil
 }
 
-func initializeDNSResolver(cfg kuma_cp.Config, builder *core_runtime.Builder) {
-	builder.WithDNSResolver(resolver.NewDNSResolver(cfg.DNSServer.Domain))
-}
-
 func initializeConfigManager(builder *core_runtime.Builder) {
 	builder.WithConfigManager(config_manager.NewConfigManager(builder.ConfigStore()))
 }

diff --git a/pkg/core/runtime/builder.go b/pkg/core/runtime/builder.go
@@ -20,7 +20,6 @@ import (
 	core_store "github.com/kumahq/kuma/pkg/core/resources/store"
 	"github.com/kumahq/kuma/pkg/core/runtime/component"
 	"github.com/kumahq/kuma/pkg/core/secrets/store"
-	"github.com/kumahq/kuma/pkg/dns/resolver"
 	dp_server "github.com/kumahq/kuma/pkg/dp-server/server"
 	"github.com/kumahq/kuma/pkg/envoy/admin"
 	"github.com/kumahq/kuma/pkg/events"
@@ -40,7 +39,6 @@ type BuilderContext interface {
 	Config() kuma_cp.Config
 	DataSourceLoader() datasource.Loader
 	Extensions() context.Context
-	DNSResolver() resolver.DNSResolver
 	ConfigManager() config_manager.ConfigManager
 	LeaderInfo() component.LeaderInfo
 	Metrics() metrics.Metrics
@@ -69,7 +67,6 @@ type Builder struct {
 	cam            core_ca.Managers
 	dsl            datasource.Loader
 	ext            context.Context
-	dns            resolver.DNSResolver
 	configm        config_manager.ConfigManager
 	leadInfo       component.LeaderInfo
 	lif            lookup.LookupIPFunc
@@ -162,11 +159,6 @@ func (b *Builder) WithExtension(key interface{}, value interface{}) *Builder {
 	return b
 }
 
-func (b *Builder) WithDNSResolver(dns resolver.DNSResolver) *Builder {
-	b.dns = dns
-	return b
-}
-
 func (b *Builder) WithConfigManager(configm config_manager.ConfigManager) *Builder {
 	b.configm = configm
 	return b
@@ -261,9 +253,6 @@ func (b *Builder) Build() (Runtime, error) {
 	if b.ext == nil {
 		return nil, errors.Errorf("Extensions have been misconfigured")
 	}
-	if b.dns == nil {
-		return nil, errors.Errorf("DNS has been misconfigured")
-	}
 	if b.leadInfo == nil {
 		return nil, errors.Errorf("LeaderInfo has not been configured")
 	}
@@ -314,7 +303,6 @@ func (b *Builder) Build() (Runtime, error) {
 			cam:            b.cam,
 			dsl:            b.dsl,
 			ext:            b.ext,
-			dns:            b.dns,
 			configm:        b.configm,
 			leadInfo:       b.leadInfo,
 			lif:            b.lif,
@@ -366,9 +354,6 @@ func (b *Builder) DataSourceLoader() datasource.Loader {
 func (b *Builder) Extensions() context.Context {
 	return b.ext
 }
-func (b *Builder) DNSResolver() resolver.DNSResolver {
-	return b.dns
-}
 func (b *Builder) ConfigManager() config_manager.ConfigManager {
 	return b.configm
 }

diff --git a/pkg/core/runtime/component/component.go b/pkg/core/runtime/component/component.go
@@ -33,6 +33,18 @@ func (f ComponentFunc) Start(stop <-chan struct{}) error {
 	return f(stop)
 }
 
+var _ Component = LeaderComponentFunc(nil)
+
+type LeaderComponentFunc func(<-chan struct{}) error
+
+func (f LeaderComponentFunc) NeedLeaderElection() bool {
+	return true
+}
+
+func (f LeaderComponentFunc) Start(stop <-chan struct{}) error {
+	return f(stop)
+}
+
 type Manager interface {
 
 	// Add registers a component, i.e. gRPC Server, HTTP server, reconciliation loop.

diff --git a/pkg/core/runtime/runtime.go b/pkg/core/runtime/runtime.go
@@ -19,7 +19,6 @@ import (
 	core_store "github.com/kumahq/kuma/pkg/core/resources/store"
 	"github.com/kumahq/kuma/pkg/core/runtime/component"
 	"github.com/kumahq/kuma/pkg/core/secrets/store"
-	"github.com/kumahq/kuma/pkg/dns/resolver"
 	dp_server "github.com/kumahq/kuma/pkg/dp-server/server"
 	"github.com/kumahq/kuma/pkg/envoy/admin"
 	"github.com/kumahq/kuma/pkg/envoy/admin/access"
@@ -56,7 +55,6 @@ type RuntimeContext interface {
 	ConfigStore() core_store.ResourceStore
 	CaManagers() ca.Managers
 	Extensions() context.Context
-	DNSResolver() resolver.DNSResolver
 	ConfigManager() config_manager.ConfigManager
 	LeaderInfo() component.LeaderInfo
 	LookupIP() lookup.LookupIPFunc
@@ -140,7 +138,6 @@ type runtimeContext struct {
 	cam            ca.Managers
 	dsl            datasource.Loader
 	ext            context.Context
-	dns            resolver.DNSResolver
 	configm        config_manager.ConfigManager
 	leadInfo       component.LeaderInfo
 	lif            lookup.LookupIPFunc
@@ -203,10 +200,6 @@ func (rc *runtimeContext) Extensions() context.Context {
 	return rc.ext
 }
 
-func (rc *runtimeContext) DNSResolver() resolver.DNSResolver {
-	return rc.dns
-}
-
 func (rc *runtimeContext) ConfigManager() config_manager.ConfigManager {
 	return rc.configm
 }

diff --git a/pkg/dns/components.go b/pkg/dns/components.go
diff --git a/pkg/dns/name_modifier.go b/pkg/dns/name_modifier.go
diff --git a/pkg/dns/name_modifier_test.go b/pkg/dns/name_modifier_test.go