diff --git a/common/cert/cert.go b/common/cert/cert.go
index f8e826e2..274ef55e 100644
--- a/common/cert/cert.go
+++ b/common/cert/cert.go
@@ -152,9 +152,11 @@ func (c *Config) NewTLSConfigForHost(hostname string) *tls.Config {
 }
 
 func (c *Config) GetOrCreateCert(hostname string, ips ...net.IP) (*tls.Certificate, error) {
+	var leaf *x509.Certificate
 	tlsCertificate, ok := c.certsStorage.Get(hostname)
 	if ok {
-		if _, err := tlsCertificate.Leaf.Verify(x509.VerifyOptions{
+		leaf = tlsCertificate.Leaf
+		if _, err := leaf.Verify(x509.VerifyOptions{
 			DNSName: hostname,
 			Roots:   c.roots,
 		}); err == nil {
@@ -163,28 +165,40 @@ func (c *Config) GetOrCreateCert(hostname string, ips ...net.IP) (*tls.Certifica
 	}
 
 	var (
-		key      = hostname
-		topHost  = hostname
-		dnsNames []string
+		key          = hostname
+		topHost      = hostname
+		wildcardHost = "*." + hostname
+		dnsNames     []string
 	)
 
 	if ip := net.ParseIP(hostname); ip != nil {
 		ips = append(ips, ip)
 	} else {
-		parts := strings.Split(topHost, ".")
+		parts := strings.Split(hostname, ".")
 		l := len(parts)
 
-		if l >= 2 {
-			for i := l - 2; i >= 0; i-- {
-				topHost = strings.Join(parts[i:], ".")
-				dnsNames = append(dnsNames, topHost, "*."+topHost)
-			}
-
-			topHost = strings.Join(parts[l-2:], ".")
-			key = "+." + topHost
-		} else {
-			dnsNames = append(dnsNames, topHost)
+		if leaf != nil {
+			dnsNames = append(dnsNames, leaf.DNSNames...)
 		}
+
+		if l > 2 {
+			topIndex := l - 2
+			topHost = strings.Join(parts[topIndex:], ".")
+
+			for i := topIndex; i > 0; i-- {
+				wildcardHost = "*." + strings.Join(parts[i:], ".")
+
+				if i == topIndex && (len(dnsNames) == 0 || dnsNames[0] != topHost) {
+					dnsNames = append(dnsNames, topHost, wildcardHost)
+				} else if !hasDnsNames(dnsNames, wildcardHost) {
+					dnsNames = append(dnsNames, wildcardHost)
+				}
+			}
+		} else {
+			dnsNames = append(dnsNames, topHost, wildcardHost)
+		}
+
+		key = "+." + topHost
 	}
 
 	serial := atomic.AddInt64(&currentSerialNumber, 1)
@@ -279,3 +293,12 @@ func GenerateAndSave(caPath string, caKeyPath string) error {
 
 	return nil
 }
+
+func hasDnsNames(dnsNames []string, hostname string) bool {
+	for _, name := range dnsNames {
+		if name == hostname {
+			return true
+		}
+	}
+	return false
+}
diff --git a/common/cert/cert_test.go b/common/cert/cert_test.go
index de8202d9..c237c588 100644
--- a/common/cert/cert_test.go
+++ b/common/cert/cert_test.go
@@ -24,13 +24,13 @@ func TestCert(t *testing.T) {
 	c.SetValidity(20 * time.Hour)
 	c.SetOrganization("Test Organization")
 
-	conf := c.NewTLSConfigForHost("abc.example.org")
+	conf := c.NewTLSConfigForHost("example.org")
 	assert.Equal(t, []string{"http/1.1"}, conf.NextProtos)
 	assert.True(t, conf.InsecureSkipVerify)
 
 	// Test generating a certificate
 	clientHello := &tls.ClientHelloInfo{
-		ServerName: "abc.example.org",
+		ServerName: "example.org",
 	}
 	tlsCert, err := conf.GetCertificate(clientHello)
 	assert.Nil(t, err)
@@ -41,22 +41,41 @@ func TestCert(t *testing.T) {
 	assert.Equal(t, "example.org", x509c.Subject.CommonName)
 	assert.Nil(t, x509c.VerifyHostname("example.org"))
 	assert.Nil(t, x509c.VerifyHostname("abc.example.org"))
-	assert.Nil(t, x509c.VerifyHostname("efg.abc.example.org"))
 	assert.Equal(t, []string{"Test Organization"}, x509c.Subject.Organization)
 	assert.NotNil(t, x509c.SubjectKeyId)
 	assert.True(t, x509c.BasicConstraintsValid)
 	assert.True(t, x509c.KeyUsage&x509.KeyUsageKeyEncipherment == x509.KeyUsageKeyEncipherment)
 	assert.True(t, x509c.KeyUsage&x509.KeyUsageDigitalSignature == x509.KeyUsageDigitalSignature)
 	assert.Equal(t, []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}, x509c.ExtKeyUsage)
-	assert.Equal(t, []string{"example.org", "*.example.org", "abc.example.org", "*.abc.example.org"}, x509c.DNSNames)
+	assert.Equal(t, []string{"example.org", "*.example.org"}, x509c.DNSNames)
 	assert.True(t, x509c.NotBefore.Before(time.Now().Add(-2*time.Hour)))
 	assert.True(t, x509c.NotAfter.After(time.Now().Add(2*time.Hour)))
 
 	// Check that certificate is cached
-	tlsCert2, err := c.GetOrCreateCert("example.org")
+	tlsCert2, err := c.GetOrCreateCert("abc.example.org")
 	assert.Nil(t, err)
 	assert.True(t, tlsCert == tlsCert2)
 
+	// Check that certificate is new
+	_, _ = c.GetOrCreateCert("a.b.c.d.e.f.g.h.i.j.example.org")
+	tlsCert3, err := c.GetOrCreateCert("m.k.l.example.org")
+	x509c = tlsCert3.Leaf
+	assert.Nil(t, err)
+	assert.False(t, tlsCert == tlsCert3)
+	assert.Equal(t, []string{"example.org", "*.example.org", "*.j.example.org", "*.i.j.example.org", "*.h.i.j.example.org", "*.g.h.i.j.example.org", "*.f.g.h.i.j.example.org", "*.e.f.g.h.i.j.example.org", "*.d.e.f.g.h.i.j.example.org", "*.c.d.e.f.g.h.i.j.example.org", "*.b.c.d.e.f.g.h.i.j.example.org", "*.l.example.org", "*.k.l.example.org"}, x509c.DNSNames)
+
+	// Check that certificate is cached
+	tlsCert4, err := c.GetOrCreateCert("xyz.example.org")
+	x509c = tlsCert4.Leaf
+	assert.Nil(t, err)
+	assert.True(t, tlsCert3 == tlsCert4)
+	assert.Nil(t, x509c.VerifyHostname("example.org"))
+	assert.Nil(t, x509c.VerifyHostname("jkf.example.org"))
+	assert.Nil(t, x509c.VerifyHostname("n.j.example.org"))
+	assert.Nil(t, x509c.VerifyHostname("c.i.j.example.org"))
+	assert.Nil(t, x509c.VerifyHostname("m.l.example.org"))
+	assert.Error(t, x509c.VerifyHostname("m.l.jkf.example.org"))
+
 	// Check the certificate for an IP
 	tlsCertForIP, err := c.GetOrCreateCert("192.168.0.1")
 	x509c = tlsCertForIP.Leaf
@@ -64,6 +83,7 @@ func TestCert(t *testing.T) {
 	assert.Equal(t, 1, len(x509c.IPAddresses))
 	assert.True(t, net.ParseIP("192.168.0.1").Equal(x509c.IPAddresses[0]))
 
+	// Check that certificate is cached
 	tlsCertForIP2, err := c.GetOrCreateCert("192.168.0.1")
 	x509c = tlsCertForIP2.Leaf
 	assert.Nil(t, err)