diff --git a/build/scripts/Complement.Dockerfile b/build/scripts/Complement.Dockerfile
index 55b381ba5..401695abf 100644
--- a/build/scripts/Complement.Dockerfile
+++ b/build/scripts/Complement.Dockerfile
@@ -12,10 +12,14 @@ COPY . .
 RUN go build ./cmd/dendrite-monolith-server
 RUN go build ./cmd/generate-keys
 RUN go build ./cmd/generate-config
-RUN ./generate-config --ci > dendrite.yaml
-RUN ./generate-keys --private-key matrix_key.pem --tls-cert server.crt --tls-key server.key
+RUN ./generate-keys --private-key matrix_key.pem
 
 ENV SERVER_NAME=localhost
 EXPOSE 8008 8448
 
-CMD sed -i "s/server_name: localhost/server_name: ${SERVER_NAME}/g" dendrite.yaml && ./dendrite-monolith-server --tls-cert server.crt --tls-key server.key --config dendrite.yaml
+# At runtime, generate TLS cert based on the CA now mounted at /ca
+# At runtime, replace the SERVER_NAME with what we are told
+CMD ./generate-keys --server $SERVER_NAME --tls-cert server.crt --tls-key server.key --tls-authority-cert /ca/ca.crt --tls-authority-key /ca/ca.key && \
+ ./generate-config -server $SERVER_NAME --ci > dendrite.yaml && \
+ cp /ca/ca.crt /usr/local/share/ca-certificates/ && update-ca-certificates && \
+ ./dendrite-monolith-server --tls-cert server.crt --tls-key server.key --config dendrite.yaml
diff --git a/cmd/generate-config/main.go b/cmd/generate-config/main.go
index a79470d83..60729672e 100644
--- a/cmd/generate-config/main.go
+++ b/cmd/generate-config/main.go
@@ -83,7 +83,7 @@ func main() {
 	if *defaultsForCI {
 		cfg.AppServiceAPI.DisableTLSValidation = true
 		cfg.ClientAPI.RateLimiting.Enabled = false
-		cfg.FederationAPI.DisableTLSValidation = true
+		cfg.FederationAPI.DisableTLSValidation = false
 		// don't hit matrix.org when running tests!!!
 		cfg.FederationAPI.KeyPerspectives = config.KeyPerspectives{}
 		cfg.MSCs.MSCs = []string{"msc2836", "msc2946", "msc2444", "msc2753"}
diff --git a/cmd/generate-keys/main.go b/cmd/generate-keys/main.go
index 743109f13..bddf219dc 100644
--- a/cmd/generate-keys/main.go
+++ b/cmd/generate-keys/main.go
@@ -32,9 +32,12 @@ Arguments:
 `
 
 var (
-	tlsCertFile    = flag.String("tls-cert", "", "An X509 certificate file to generate for use for TLS")
-	tlsKeyFile     = flag.String("tls-key", "", "An RSA private key file to generate for use for TLS")
-	privateKeyFile = flag.String("private-key", "", "An Ed25519 private key to generate for use for object signing")
+	tlsCertFile       = flag.String("tls-cert", "", "An X509 certificate file to generate for use for TLS")
+	tlsKeyFile        = flag.String("tls-key", "", "An RSA private key file to generate for use for TLS")
+	privateKeyFile    = flag.String("private-key", "", "An Ed25519 private key to generate for use for object signing")
+	authorityCertFile = flag.String("tls-authority-cert", "", "Optional: Create TLS certificate/keys based on this CA authority. Useful for integration testing.")
+	authorityKeyFile  = flag.String("tls-authority-key", "", "Optional: Create TLS certificate/keys based on this CA authority. Useful for integration testing.")
+	serverName        = flag.String("server", "", "Optional: Create TLS certificate/keys with this domain name set. Useful for integration testing.")
 )
 
 func main() {
@@ -54,8 +57,15 @@ func main() {
 		if *tlsCertFile == "" || *tlsKeyFile == "" {
 			log.Fatal("Zero or both of --tls-key and --tls-cert must be supplied")
 		}
-		if err := test.NewTLSKey(*tlsKeyFile, *tlsCertFile); err != nil {
-			panic(err)
+		if *authorityCertFile == "" && *authorityKeyFile == "" {
+			if err := test.NewTLSKey(*tlsKeyFile, *tlsCertFile); err != nil {
+				panic(err)
+			}
+		} else {
+			// generate the TLS cert/key based on the authority given.
+			if err := test.NewTLSKeyWithAuthority(*serverName, *tlsKeyFile, *tlsCertFile, *authorityKeyFile, *authorityCertFile); err != nil {
+				panic(err)
+			}
 		}
 		fmt.Printf("Created TLS cert file:    %s\n", *tlsCertFile)
 		fmt.Printf("Created TLS key file:     %s\n", *tlsKeyFile)
diff --git a/internal/test/config.go b/internal/test/config.go
index bb2f8a4c6..4fb6a946c 100644
--- a/internal/test/config.go
+++ b/internal/test/config.go
@@ -20,6 +20,7 @@ import (
 	"crypto/x509"
 	"encoding/base64"
 	"encoding/pem"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"math/big"
@@ -158,11 +159,10 @@ func NewMatrixKey(matrixKeyPath string) (err error) {
 
 const certificateDuration = time.Hour * 24 * 365 * 10
 
-// NewTLSKey generates a new RSA TLS key and certificate and writes it to a file.
-func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
+func generateTLSTemplate(dnsNames []string) (*rsa.PrivateKey, *x509.Certificate, error) {
 	priv, err := rsa.GenerateKey(rand.Reader, 4096)
 	if err != nil {
-		return err
+		return nil, nil, err
 	}
 
 	notBefore := time.Now()
@@ -170,7 +170,7 @@ func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
 	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
 	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
 	if err != nil {
-		return err
+		return nil, nil, err
 	}
 
 	template := x509.Certificate{
@@ -180,20 +180,21 @@ func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
 		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
 		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
 		BasicConstraintsValid: true,
+		DNSNames:              dnsNames,
 	}
-	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, &priv.PublicKey, priv)
-	if err != nil {
-		return err
-	}
+	return priv, &template, nil
+}
+
+func writeCertificate(tlsCertPath string, derBytes []byte) error {
 	certOut, err := os.Create(tlsCertPath)
 	if err != nil {
 		return err
 	}
 	defer certOut.Close() // nolint: errcheck
-	if err = pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes}); err != nil {
-		return err
-	}
+	return pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+}
 
+func writePrivateKey(tlsKeyPath string, priv *rsa.PrivateKey) error {
 	keyOut, err := os.OpenFile(tlsKeyPath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
 	if err != nil {
 		return err
@@ -205,3 +206,73 @@ func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
 	})
 	return err
 }
+
+// NewTLSKey generates a new RSA TLS key and certificate and writes it to a file.
+func NewTLSKey(tlsKeyPath, tlsCertPath string) error {
+	priv, template, err := generateTLSTemplate(nil)
+	if err != nil {
+		return err
+	}
+
+	// Self-signed certificate: template == parent
+	derBytes, err := x509.CreateCertificate(rand.Reader, template, template, &priv.PublicKey, priv)
+	if err != nil {
+		return err
+	}
+
+	if err = writeCertificate(tlsCertPath, derBytes); err != nil {
+		return err
+	}
+	return writePrivateKey(tlsKeyPath, priv)
+}
+
+func NewTLSKeyWithAuthority(serverName, tlsKeyPath, tlsCertPath, authorityKeyPath, authorityCertPath string) error {
+	priv, template, err := generateTLSTemplate([]string{serverName})
+	if err != nil {
+		return err
+	}
+
+	// load the authority key
+	dat, err := ioutil.ReadFile(authorityKeyPath)
+	if err != nil {
+		return err
+	}
+	block, _ := pem.Decode([]byte(dat))
+	if block == nil || block.Type != "RSA PRIVATE KEY" {
+		return errors.New("authority .key is not a valid pem encoded rsa private key")
+	}
+	authorityPriv, err := x509.ParsePKCS1PrivateKey(block.Bytes)
+	if err != nil {
+		return err
+	}
+
+	// load the authority certificate
+	dat, err = ioutil.ReadFile(authorityCertPath)
+	if err != nil {
+		return err
+	}
+	block, _ = pem.Decode([]byte(dat))
+	if block == nil || block.Type != "CERTIFICATE" {
+		return errors.New("authority .crt is not a valid pem encoded x509 cert")
+	}
+	var caCerts []*x509.Certificate
+	caCerts, err = x509.ParseCertificates(block.Bytes)
+	if err != nil {
+		return err
+	}
+	if len(caCerts) != 1 {
+		return errors.New("authority .crt contains none or more than one cert")
+	}
+	authorityCert := caCerts[0]
+
+	// Sign the new certificate using the authority's key/cert
+	derBytes, err := x509.CreateCertificate(rand.Reader, template, authorityCert, &priv.PublicKey, authorityPriv)
+	if err != nil {
+		return err
+	}
+
+	if err = writeCertificate(tlsCertPath, derBytes); err != nil {
+		return err
+	}
+	return writePrivateKey(tlsKeyPath, priv)
+}