diff --git a/go/config/config.go b/go/config/config.go
index 3c1ad4c80..170375e2a 100644
--- a/go/config/config.go
+++ b/go/config/config.go
@@ -255,6 +255,8 @@ type Configuration struct {
 	GraphitePollSeconds                        int               // Graphite writes interval. 0 disables.
 	URLPrefix                                  string            // URL prefix to run orchestrator on non-root web path, e.g. /orchestrator to put it behind nginx.
 	DiscoveryIgnoreReplicaHostnameFilters      []string          // Regexp filters to apply to prevent auto-discovering new replicas. Usage: unreachable servers due to firewalls, applications which trigger binlog dumps
+	DiscoveryIgnoreMasterHostnameFilters       []string          // Regexp filters to apply to prevent auto-discovering a master. Usage: pointing your master temporarily to replicate seom data from external host
+	DiscoveryIgnoreHostnameFilters             []string          // Regexp filters to apply to prevent discovering instances of any kind
 	ConsulAddress                              string            // Address where Consul HTTP api is found. Example: 127.0.0.1:8500
 	ConsulAclToken                             string            // ACL token used to write to Consul KV
 	ConsulCrossDataCenterDistribution          bool              // should orchestrator automatically auto-deduce all consul DCs and write KVs in all DCs
diff --git a/go/inst/analysis_test.go b/go/inst/analysis_test.go
new file mode 100644
index 000000000..9ad5d7dbf
--- /dev/null
+++ b/go/inst/analysis_test.go
@@ -0,0 +1,49 @@
+/*
+   Copyright 2014 Outbrain Inc.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package inst
+
+import (
+	"github.com/github/orchestrator/go/config"
+	"github.com/openark/golib/log"
+	// test "github.com/openark/golib/tests"
+	"testing"
+)
+
+func init() {
+	config.Config.HostnameResolveMethod = "none"
+	config.MarkConfigurationLoaded()
+	log.SetLevel(log.ERROR)
+}
+
+func TestGetAnalysisInstanceType(t *testing.T) {
+	// {
+	// 	analysis := &ReplicationAnalysis{}
+	// 	test.S(t).ExpectEquals(string(analysis.GetAnalysisInstanceType()), "intermediate-master")
+	// }
+	// {
+	// 	analysis := &ReplicationAnalysis{IsMaster: true}
+	// 	test.S(t).ExpectEquals(string(analysis.GetAnalysisInstanceType()), "master")
+	// }
+	// {
+	// 	analysis := &ReplicationAnalysis{IsCoMaster: true}
+	// 	test.S(t).ExpectEquals(string(analysis.GetAnalysisInstanceType()), "co-master")
+	// }
+	// {
+	// 	analysis := &ReplicationAnalysis{IsMaster: true, IsCoMaster: true}
+	// 	test.S(t).ExpectEquals(string(analysis.GetAnalysisInstanceType()), "co-master")
+	// }
+}
diff --git a/go/inst/instance_dao.go b/go/inst/instance_dao.go
index afc35451f..c65a1a793 100644
--- a/go/inst/instance_dao.go
+++ b/go/inst/instance_dao.go
@@ -1827,6 +1827,16 @@ func InjectUnseenMasters() error {
 	operations := 0
 	for _, masterKey := range unseenMasterKeys {
 		masterKey := masterKey
+
+		if RegexpMatchPatterns(masterKey.StringCode(), config.Config.DiscoveryIgnoreMasterHostnameFilters) {
+			log.Debugf("InjectUnseenMasters: skipping discovery of %+v because it matches DiscoveryIgnoreMasterHostnameFilters", masterKey)
+			continue
+		}
+		if RegexpMatchPatterns(masterKey.StringCode(), config.Config.DiscoveryIgnoreHostnameFilters) {
+			log.Debugf("InjectUnseenMasters: skipping discovery of %+v because it matches DiscoveryIgnoreHostnameFilters", masterKey)
+			continue
+		}
+
 		clusterName := masterKey.StringCode()
 		// minimal details:
 		instance := Instance{Key: masterKey, Version: "Unknown", ClusterName: clusterName}
diff --git a/go/logic/orchestrator.go b/go/logic/orchestrator.go
index 54578df72..5a01f9698 100644
--- a/go/logic/orchestrator.go
+++ b/go/logic/orchestrator.go
@@ -190,6 +190,11 @@ func DiscoverInstance(instanceKey inst.InstanceKey) {
 		log.Debugf("discoverInstance: skipping discovery of %+v because it is set to be forgotten", instanceKey)
 		return
 	}
+	if inst.RegexpMatchPatterns(instanceKey.StringCode(), config.Config.DiscoveryIgnoreHostnameFilters) {
+		log.Debugf("discoverInstance: skipping discovery of %+v because it matches DiscoveryIgnoreHostnameFilters", instanceKey)
+		return
+	}
+
 	// create stopwatch entries
 	latency := stopwatch.NewNamedStopwatch()
 	latency.AddMany([]string{
@@ -289,7 +294,9 @@ func DiscoverInstance(instanceKey inst.InstanceKey) {
 	}
 	// Investigate master:
 	if instance.MasterKey.IsValid() {
-		discoveryQueue.Push(instance.MasterKey)
+		if !inst.RegexpMatchPatterns(instance.MasterKey.StringCode(), config.Config.DiscoveryIgnoreMasterHostnameFilters) {
+			discoveryQueue.Push(instance.MasterKey)
+		}
 	}
 }