implement basic status checking
diff --git a/Gopkg.lock b/Gopkg.lock
index 977c48a..9058ae0 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -2,6 +2,14 @@
 
 
 [[projects]]
+  branch = "master"
+  digest = "1:2af0bc306f77bef606f6f6033652f0de3cc80e77008f4da52197b4b0a6be5853"
+  name = "code.hackerspace.pl/q3k/hspki"
+  packages = ["."]
+  pruneopts = "UT"
+  revision = "624295da664fea57a1e3bd8cee639ae04f4c0ccf"
+
+[[projects]]
   digest = "1:d1665c44bd5db19aaee18d1b6233c99b0b9a986e8bccb24ef54747547a48027f"
   name = "github.com/PuerkitoBio/purell"
   packages = ["."]
@@ -358,6 +366,7 @@
   analyzer-name = "dep"
   analyzer-version = 1
   input-imports = [
+    "code.hackerspace.pl/q3k/hspki",
     "github.com/digitalocean/go-netbox/netbox",
     "github.com/digitalocean/go-netbox/netbox/client",
     "github.com/digitalocean/go-netbox/netbox/client/dcim",
diff --git a/config.proto b/config.proto
index e569fb2..f1054be 100644
--- a/config.proto
+++ b/config.proto
@@ -7,18 +7,11 @@
 
 message Switch {
     string name = 1;
-
-    enum Connector {
-        CONNECTOR_INVALID = 0;
-        CONNECTOR_M6220 = 1;
-        CONNECTOR_ARISTA = 2;
-    };
-    Connector connector = 2;
-    string address = 3;
+    string control_address = 2;
     message SwitchPort {
         string name = 1;
     };
-    repeated SwitchPort managed_port = 4;
+    repeated SwitchPort managed_port = 3;
     message Segment {
         enum Type {
             TYPE_INVALID = 0;
@@ -27,7 +20,7 @@
         Type segment_type = 1;
         int32 vlan_id = 2;
     };
-    repeated Segment available_segment = 5;
+    repeated Segment available_segment = 4;
 };
 
 message Machine {
diff --git a/graph/graph.go b/graph/graph.go
index 911924f..a5139e6 100644
--- a/graph/graph.go
+++ b/graph/graph.go
@@ -3,6 +3,7 @@
 import (
 	"context"
 	"fmt"
+	"sync"
 
 	"github.com/digitalocean/go-netbox/netbox/client"
 	"github.com/digitalocean/go-netbox/netbox/client/dcim"
@@ -41,6 +42,7 @@
 type Graph struct {
 	Switches map[string]*Switch
 	Machines map[string]*Machine
+	Mu       sync.RWMutex
 }
 
 func New() *Graph {
diff --git a/main.go b/main.go
index c538eaa..87675bc 100644
--- a/main.go
+++ b/main.go
@@ -46,6 +46,12 @@
 	config := confpb.Config{}
 	proto.UnmarshalText(string(data), &config)
 
+	stm := state.NewManager()
+	err = stm.FetchState(ctx, &config)
+	if err != nil {
+		glog.Exitf("Initial state fetch failed: %v", err)
+	}
+
 	gr := graph.New()
 	err = gr.LoadConfig(&config)
 	if err != nil {
@@ -59,8 +65,6 @@
 		glog.Exitf("Initial netbox feed failed: %v", err)
 	}
 
-	stm := state.NewManager()
-
 	sconf := ServiceConfig{
 		DebugListen: flagDebugListen,
 	}
diff --git a/proto/config/config.pb.go b/proto/config/config.pb.go
index 69aac41..e5ef9a3 100644
--- a/proto/config/config.pb.go
+++ b/proto/config/config.pb.go
@@ -20,34 +20,6 @@
 // proto package needs to be updated.
 const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 
-type Switch_Connector int32
-
-const (
-	Switch_CONNECTOR_INVALID Switch_Connector = 0
-	Switch_CONNECTOR_M6220   Switch_Connector = 1
-	Switch_CONNECTOR_ARISTA  Switch_Connector = 2
-)
-
-var Switch_Connector_name = map[int32]string{
-	0: "CONNECTOR_INVALID",
-	1: "CONNECTOR_M6220",
-	2: "CONNECTOR_ARISTA",
-}
-
-var Switch_Connector_value = map[string]int32{
-	"CONNECTOR_INVALID": 0,
-	"CONNECTOR_M6220":   1,
-	"CONNECTOR_ARISTA":  2,
-}
-
-func (x Switch_Connector) String() string {
-	return proto.EnumName(Switch_Connector_name, int32(x))
-}
-
-func (Switch_Connector) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_3eaf2c85e69e9ea4, []int{1, 0}
-}
-
 type Switch_Segment_Type int32
 
 const (
@@ -122,10 +94,9 @@
 
 type Switch struct {
 	Name                 string               `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`
-	Connector            Switch_Connector     `protobuf:"varint,2,opt,name=connector,proto3,enum=Switch_Connector" json:"connector,omitempty"`
-	Address              string               `protobuf:"bytes,3,opt,name=address,proto3" json:"address,omitempty"`
-	ManagedPort          []*Switch_SwitchPort `protobuf:"bytes,4,rep,name=managed_port,json=managedPort,proto3" json:"managed_port,omitempty"`
-	AvailableSegment     []*Switch_Segment    `protobuf:"bytes,5,rep,name=available_segment,json=availableSegment,proto3" json:"available_segment,omitempty"`
+	ControlAddress       string               `protobuf:"bytes,2,opt,name=control_address,json=controlAddress,proto3" json:"control_address,omitempty"`
+	ManagedPort          []*Switch_SwitchPort `protobuf:"bytes,3,rep,name=managed_port,json=managedPort,proto3" json:"managed_port,omitempty"`
+	AvailableSegment     []*Switch_Segment    `protobuf:"bytes,4,rep,name=available_segment,json=availableSegment,proto3" json:"available_segment,omitempty"`
 	XXX_NoUnkeyedLiteral struct{}             `json:"-"`
 	XXX_unrecognized     []byte               `json:"-"`
 	XXX_sizecache        int32                `json:"-"`
@@ -163,16 +134,9 @@
 	return ""
 }
 
-func (m *Switch) GetConnector() Switch_Connector {
+func (m *Switch) GetControlAddress() string {
 	if m != nil {
-		return m.Connector
-	}
-	return Switch_CONNECTOR_INVALID
-}
-
-func (m *Switch) GetAddress() string {
-	if m != nil {
-		return m.Address
+		return m.ControlAddress
 	}
 	return ""
 }
@@ -364,7 +328,6 @@
 }
 
 func init() {
-	proto.RegisterEnum("Switch_Connector", Switch_Connector_name, Switch_Connector_value)
 	proto.RegisterEnum("Switch_Segment_Type", Switch_Segment_Type_name, Switch_Segment_Type_value)
 	proto.RegisterType((*Config)(nil), "Config")
 	proto.RegisterType((*Switch)(nil), "Switch")
@@ -377,30 +340,26 @@
 func init() { proto.RegisterFile("config.proto", fileDescriptor_3eaf2c85e69e9ea4) }
 
 var fileDescriptor_3eaf2c85e69e9ea4 = []byte{
-	// 394 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x74, 0x92, 0xc1, 0x6e, 0x9b, 0x40,
-	0x10, 0x86, 0x8b, 0x4d, 0xa0, 0x8c, 0x49, 0x82, 0xb7, 0xa9, 0xba, 0xe2, 0x52, 0xc4, 0xa5, 0x3e,
-	0xd1, 0x88, 0xaa, 0xed, 0xa5, 0x17, 0x44, 0x73, 0x40, 0x0a, 0x24, 0xda, 0xa0, 0x48, 0x3d, 0xa1,
-	0x0d, 0x6c, 0x1d, 0x54, 0xb3, 0x20, 0x40, 0xae, 0x7c, 0xef, 0x23, 0xf6, 0x81, 0x2a, 0x2f, 0x8b,
-	0xa9, 0x5c, 0xf7, 0x04, 0xff, 0x3f, 0xdf, 0xcc, 0xc0, 0xcc, 0x80, 0x99, 0xd7, 0xfc, 0x7b, 0xb9,
-	0xf6, 0x9a, 0xb6, 0xee, 0x6b, 0x37, 0x06, 0x2d, 0x14, 0x1a, 0xbd, 0x05, 0xad, 0xfb, 0x59, 0xf6,
-	0xf9, 0x33, 0x56, 0x9c, 0xf9, 0x6a, 0xe1, 0xeb, 0xde, 0x83, 0x90, 0x44, 0xda, 0xc8, 0x05, 0xbd,
-	0xa2, 0xf9, 0x73, 0xc9, 0x19, 0x9e, 0x09, 0xe2, 0xa5, 0x17, 0x0f, 0x9a, 0x8c, 0x01, 0xf7, 0xf7,
-	0x1c, 0xb4, 0x21, 0x0d, 0x21, 0x50, 0x39, 0xad, 0x18, 0x56, 0x1c, 0x65, 0x65, 0x10, 0xf1, 0x8e,
-	0xde, 0x83, 0x91, 0xd7, 0x9c, 0xb3, 0xbc, 0xaf, 0x5b, 0x3c, 0x73, 0x94, 0xd5, 0x85, 0xbf, 0x94,
-	0x6d, 0xbc, 0x70, 0x0c, 0x90, 0x89, 0x41, 0x18, 0x74, 0x5a, 0x14, 0x2d, 0xeb, 0x3a, 0x3c, 0x17,
-	0x75, 0x46, 0x89, 0x3e, 0x82, 0x59, 0x51, 0x4e, 0xd7, 0xac, 0xc8, 0x9a, 0xba, 0xed, 0xb1, 0x2a,
-	0x3e, 0x09, 0x8d, 0xd5, 0x86, 0xc7, 0x7d, 0xdd, 0xf6, 0x64, 0x21, 0xb9, 0xbd, 0x40, 0x5f, 0x60,
-	0x49, 0xb7, 0xb4, 0xdc, 0xd0, 0xa7, 0x0d, 0xcb, 0x3a, 0xb6, 0xae, 0x18, 0xef, 0xf1, 0x99, 0xc8,
-	0xbd, 0x3c, 0xe4, 0x0e, 0x36, 0xb1, 0x0e, 0xa4, 0x74, 0x6c, 0x07, 0x60, 0x2a, 0x7c, 0xea, 0x0f,
-	0xed, 0x5f, 0x0a, 0xe8, 0x92, 0x46, 0x9f, 0xc1, 0x94, 0x1d, 0xb2, 0x7e, 0xd7, 0x0c, 0xdc, 0x85,
-	0x7f, 0x75, 0xd4, 0xc6, 0x4b, 0x77, 0x0d, 0x23, 0x0b, 0x49, 0xee, 0x05, 0x7a, 0x03, 0xfa, 0x76,
-	0x43, 0x79, 0x56, 0x16, 0x62, 0x48, 0x67, 0x44, 0xdb, 0xcb, 0xa8, 0x70, 0xdf, 0x81, 0x2a, 0x00,
-	0x0b, 0xcc, 0xf4, 0xdb, 0xfd, 0x4d, 0x16, 0x25, 0x8f, 0xc1, 0x6d, 0xf4, 0xd5, 0x7a, 0x81, 0xce,
-	0xc1, 0x10, 0xce, 0xe3, 0x6d, 0x90, 0x58, 0x8a, 0x1b, 0x83, 0x71, 0x98, 0x27, 0x7a, 0x0d, 0xcb,
-	0xf0, 0x2e, 0x49, 0x6e, 0xc2, 0xf4, 0x8e, 0xfc, 0x95, 0xf2, 0x0a, 0x2e, 0x27, 0x3b, 0xfe, 0xe4,
-	0xfb, 0xd7, 0x96, 0x82, 0xae, 0xc0, 0x9a, 0xcc, 0x80, 0x44, 0x0f, 0x69, 0x60, 0xcd, 0xdc, 0x1f,
-	0xa0, 0xcb, 0x55, 0x9f, 0x5c, 0xeb, 0xf5, 0xd1, 0x2e, 0x86, 0xf3, 0x38, 0x1f, 0xcf, 0xc3, 0xfb,
-	0x67, 0x0d, 0xb6, 0x0d, 0xea, 0xff, 0x46, 0xf8, 0xa4, 0x89, 0xcb, 0xfc, 0xf0, 0x27, 0x00, 0x00,
-	0xff, 0xff, 0x30, 0x75, 0x6a, 0x03, 0xa9, 0x02, 0x00, 0x00,
+	// 335 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x74, 0x52, 0x41, 0x4f, 0xc2, 0x30,
+	0x14, 0x76, 0x30, 0x37, 0x79, 0x0c, 0x98, 0x8d, 0x89, 0xcb, 0x2e, 0x92, 0x5d, 0xe0, 0xb4, 0x18,
+	0x8c, 0xf1, 0xe2, 0x85, 0xa8, 0x07, 0x12, 0x20, 0xa4, 0x12, 0x12, 0x4f, 0x4b, 0xd9, 0x2a, 0x2c,
+	0x6e, 0xed, 0xb2, 0x35, 0x18, 0xee, 0xfe, 0x53, 0xff, 0x88, 0xa1, 0x2d, 0x98, 0x20, 0x9e, 0xda,
+	0xef, 0x7b, 0xdf, 0xeb, 0x7b, 0xef, 0x7b, 0x05, 0x27, 0xe6, 0xec, 0x3d, 0x5d, 0x85, 0x45, 0xc9,
+	0x05, 0x0f, 0x26, 0x60, 0x3d, 0x49, 0x8c, 0x6e, 0xc0, 0xaa, 0x3e, 0x53, 0x11, 0xaf, 0x3d, 0xa3,
+	0x5b, 0xef, 0x37, 0x07, 0x76, 0xf8, 0x2a, 0x21, 0xd6, 0x34, 0x0a, 0xc0, 0xce, 0x49, 0xbc, 0x4e,
+	0x19, 0xf5, 0x6a, 0x52, 0x71, 0x11, 0x4e, 0x14, 0xc6, 0xfb, 0x40, 0xf0, 0x5d, 0x03, 0x4b, 0xa5,
+	0x21, 0x04, 0x26, 0x23, 0x39, 0xf5, 0x8c, 0xae, 0xd1, 0x6f, 0x60, 0x79, 0x47, 0x3d, 0xe8, 0xc4,
+	0x9c, 0x89, 0x92, 0x67, 0x11, 0x49, 0x92, 0x92, 0x56, 0x95, 0x57, 0x93, 0xe1, 0xb6, 0xa6, 0x87,
+	0x8a, 0x45, 0xf7, 0xe0, 0xe4, 0x84, 0x91, 0x15, 0x4d, 0xa2, 0x82, 0x97, 0xc2, 0xab, 0xcb, 0x82,
+	0x48, 0xb7, 0xa4, 0x8f, 0x19, 0x2f, 0x05, 0x6e, 0x6a, 0xdd, 0x0e, 0xa0, 0x47, 0xb8, 0x24, 0x1b,
+	0x92, 0x66, 0x64, 0x99, 0xd1, 0xa8, 0xa2, 0xab, 0x9c, 0x32, 0xe1, 0x99, 0x32, 0xb7, 0x73, 0xc8,
+	0x55, 0x34, 0x76, 0x0f, 0x4a, 0xcd, 0xf8, 0x5d, 0x80, 0xdf, 0x87, 0x4f, 0xf5, 0xef, 0x7f, 0x19,
+	0x60, 0x6b, 0x35, 0x7a, 0x00, 0x47, 0x57, 0x88, 0xc4, 0xb6, 0x50, 0xba, 0xf6, 0xe0, 0xea, 0xa8,
+	0x4c, 0x38, 0xdf, 0x16, 0x14, 0x37, 0xb5, 0x72, 0x07, 0xd0, 0x35, 0xd8, 0x9b, 0x8c, 0xb0, 0x28,
+	0x4d, 0xe4, 0xf0, 0xe7, 0xd8, 0xda, 0xc1, 0x51, 0x12, 0xf4, 0xc0, 0x94, 0x02, 0x17, 0x9c, 0xf9,
+	0xdb, 0xec, 0x25, 0x1a, 0x4d, 0x17, 0xc3, 0xf1, 0xe8, 0xd9, 0x3d, 0x43, 0x2d, 0x68, 0x48, 0x66,
+	0x31, 0x1e, 0x4e, 0x5d, 0x23, 0xf8, 0x00, 0x5b, 0x3b, 0x7f, 0xd2, 0xe5, 0xdb, 0x23, 0xf3, 0xd4,
+	0xb6, 0x5a, 0xfb, 0x6d, 0x85, 0x7f, 0x7c, 0xf3, 0x7d, 0x30, 0xff, 0x9b, 0x79, 0x69, 0xc9, 0x8f,
+	0x72, 0xf7, 0x13, 0x00, 0x00, 0xff, 0xff, 0x58, 0xe3, 0x1a, 0xb1, 0x38, 0x02, 0x00, 0x00,
 }
diff --git a/service.go b/service.go
index 916299c..03fd218 100644
--- a/service.go
+++ b/service.go
@@ -14,6 +14,8 @@
 
 	"code.hackerspace.pl/q3k/topo/graph"
 	"code.hackerspace.pl/q3k/topo/state"
+
+	pb "code.hackerspace.pl/q3k/topo/proto/control"
 )
 
 type ServiceConfig struct {
@@ -34,9 +36,6 @@
 	}
 }
 
-type TopologyStatus struct {
-}
-
 const topologyFragment = `
   <script src="/assets/viz.js"></script>
   <script>
@@ -59,58 +58,179 @@
   <div id="graph" style="text-align: center;"></div>
 `
 
+const switchportsFragment = `
+    <style type="text/css">
+		.table td,th {
+			background-color: #eee;
+			padding: 0.2em 0.4em 0.2em 0.4em;
+		}
+		.table th {
+			background-color: #c0c0c0;
+		}
+		.table {
+			background-color: #fff;
+			border-spacing: 0.2em;
+			margin-left: auto;
+			margin-right: auto;
+		}
+	</style>
+	<div>
+	<table class="table">
+		<tr>
+      		<th>Switch</th>
+      		<th>Port</th>
+			<th>Link State</th>
+			<th>Port Mode</th>
+			<th>MTU</th>
+			<th>Sync Status</th>
+		</tr>
+		{{range .Ports }}
+		{{ if .Managed }}
+		<tr>
+		{{ else }}
+		<tr style="opacity: 0.5">
+		{{ end}}
+			<td style="text-align: right;">{{ .Switch }}</td>
+			<td>{{ .Name }}</td>
+			{{ if eq .State "DOWN" }}
+			<td style="background-color: #ff3030;">{{ .State }}</td>
+			{{ else }}
+			<td>{{ .State }}</td>
+			{{ end }}
+			<td>{{ .Mode }}</td>
+			<td>{{ .MTU }}</td>
+			{{ if .Managed }}
+			<td style="background-color: #30ff30;">OK</td>
+			{{ else }}
+			<td><i>Unmanaged</i></td>
+			{{ end }}
+		</tr>
+		{{end}}
+	</table>
+	</div>
+`
+
 func (s *Service) Run() {
 	assets := packr.NewBox("./assets")
 	http.Handle("/assets/", http.StripPrefix("/assets/", http.FileServer(assets)))
-
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		http.Redirect(w, r, "/debug/status", http.StatusSeeOther)
 	})
+	http.HandleFunc("/debug/graphviz", s.httpHandleGraphviz)
 
-	http.HandleFunc("/debug/graphviz", func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprintf(w, "graph G {\n")
-		fmt.Fprintf(w, "  ranksep = 2\n")
-		fmt.Fprintf(w, "  splines = polyline\n")
-		fmt.Fprintf(w, "  rankdir = LR\n")
-		for _, machine := range s.gr.Machines {
-			portNames := []string{}
-			for _, port := range machine.Ports {
-				name := fmt.Sprintf("<%s> %s", port.Name, port.Name)
-				portNames = append(portNames, name)
-			}
-			ports := strings.Join(portNames, "|")
-			fmt.Fprintf(w, "  %s [shape=record label=\"{ %s | { %s }}\"]\n", machine.Name, machine.Name, ports)
-		}
-		for _, sw := range s.gr.Switches {
-			portNames := []string{}
-			portsOrdered := []*graph.SwitchPort{}
-			for _, port := range sw.Ports {
-				portsOrdered = append(portsOrdered, port)
-			}
-			sort.Slice(portsOrdered, func(i, j int) bool {
-				return sortorder.NaturalLess(portsOrdered[i].Name, portsOrdered[j].Name)
-			})
-			for _, port := range portsOrdered {
-				name := fmt.Sprintf("<%s> %s", port.Name, port.Name)
-				portNames = append(portNames, name)
-			}
-			ports := strings.Join(portNames, "|")
-			fmt.Fprintf(w, "  %s [shape=record label=\"{{ %s } | %s}\"]\n", sw.Name, ports, sw.Name)
-		}
-		for _, machine := range s.gr.Machines {
-			for _, port := range machine.Ports {
-				if port.OtherEnd == nil {
-					continue
-				}
-				fmt.Fprintf(w, "  %s:%q:e -- %s:%q:w\n", machine.Name, port.Name, port.OtherEnd.Switch.Name, port.OtherEnd.Name)
-			}
-		}
-		fmt.Fprintf(w, "}\n")
-	})
-
+	statusz.AddStatusPart("Switch Ports", switchportsFragment, s.statusHandleSwitchports)
 	statusz.AddStatusPart("Topology", topologyFragment, func(ctx context.Context) interface{} {
-		return &TopologyStatus{}
+		return nil
 	})
 	glog.Infof("Debug listening on %s....", s.config.DebugListen)
 	http.ListenAndServe(s.config.DebugListen, nil)
 }
+
+func (s *Service) statusHandleSwitchports(ctx context.Context) interface{} {
+	managedPorts := make(map[string]bool)
+	s.gr.Mu.RLock()
+	for _, sw := range s.gr.Switches {
+		for _, port := range sw.Ports {
+			managedPorts[sw.Name+"|"+port.Name] = true
+		}
+	}
+	s.gr.Mu.RUnlock()
+
+	s.stm.Mu.RLock()
+	defer s.stm.Mu.RUnlock()
+
+	res := struct {
+		Ports []*struct {
+			Switch  string
+			Name    string
+			State   string
+			Mode    string
+			Managed bool
+			MTU     string
+		}
+	}{}
+	for _, sw := range s.stm.Switches {
+		for _, po := range sw.Ports {
+			state := "INVALID"
+			switch po.Proto.LinkState {
+			case pb.SwitchPort_LINKSTATE_DOWN:
+				state = "DOWN"
+			case pb.SwitchPort_LINKSTATE_UP:
+				state = "UP"
+			}
+			mode := "INVALID"
+			switch po.Proto.PortMode {
+			case pb.SwitchPort_PORTMODE_SWITCHPORT_UNTAGGED:
+				mode = fmt.Sprintf("UNTAGGED (%d)", po.Proto.VlanNative)
+			case pb.SwitchPort_PORTMODE_SWITCHPORT_TAGGED:
+				mode = fmt.Sprintf("TAGGED (%v)", po.Proto.VlanTagged)
+			case pb.SwitchPort_PORTMODE_SWITCHPORT_GENERIC:
+				mode = "GENERIC"
+			case pb.SwitchPort_PORTMODE_ROUTED:
+				mode = "ROUTED"
+			case pb.SwitchPort_PORTMODE_MANGLED:
+				mode = "MANGLED"
+			}
+
+			managed := managedPorts[sw.Name+"|"+po.Proto.Name]
+			res.Ports = append(res.Ports, &struct {
+				Switch  string
+				Name    string
+				State   string
+				Mode    string
+				Managed bool
+				MTU     string
+			}{
+				Switch:  sw.Name,
+				Name:    po.Proto.Name,
+				State:   state,
+				Mode:    mode,
+				Managed: managed,
+				MTU:     fmt.Sprintf("%d", po.Proto.Mtu),
+			})
+		}
+	}
+
+	return res
+}
+
+func (s *Service) httpHandleGraphviz(w http.ResponseWriter, r *http.Request) {
+	fmt.Fprintf(w, "graph G {\n")
+	fmt.Fprintf(w, "  ranksep = 2\n")
+	fmt.Fprintf(w, "  splines = polyline\n")
+	fmt.Fprintf(w, "  rankdir = LR\n")
+	for _, machine := range s.gr.Machines {
+		portNames := []string{}
+		for _, port := range machine.Ports {
+			name := fmt.Sprintf("<%s> %s", port.Name, port.Name)
+			portNames = append(portNames, name)
+		}
+		ports := strings.Join(portNames, "|")
+		fmt.Fprintf(w, "  %s [shape=record label=\"{ %s | { %s }}\"]\n", machine.Name, machine.Name, ports)
+	}
+	for _, sw := range s.gr.Switches {
+		portNames := []string{}
+		portsOrdered := []*graph.SwitchPort{}
+		for _, port := range sw.Ports {
+			portsOrdered = append(portsOrdered, port)
+		}
+		sort.Slice(portsOrdered, func(i, j int) bool {
+			return sortorder.NaturalLess(portsOrdered[i].Name, portsOrdered[j].Name)
+		})
+		for _, port := range portsOrdered {
+			name := fmt.Sprintf("<%s> %s", port.Name, port.Name)
+			portNames = append(portNames, name)
+		}
+		ports := strings.Join(portNames, "|")
+		fmt.Fprintf(w, "  %s [shape=record label=\"{{ %s } | %s}\"]\n", sw.Name, ports, sw.Name)
+	}
+	for _, machine := range s.gr.Machines {
+		for _, port := range machine.Ports {
+			if port.OtherEnd == nil {
+				continue
+			}
+			fmt.Fprintf(w, "  %s:%q:e -- %s:%q:w\n", machine.Name, port.Name, port.OtherEnd.Switch.Name, port.OtherEnd.Name)
+		}
+	}
+	fmt.Fprintf(w, "}\n")
+}
diff --git a/state/state.go b/state/state.go
index 5f7cc56..e9ccce6 100644
--- a/state/state.go
+++ b/state/state.go
@@ -1,7 +1,16 @@
 package state
 
 import (
+	"context"
+	"fmt"
+	"sync"
+
+	"google.golang.org/grpc"
+
+	cpb "code.hackerspace.pl/q3k/topo/proto/config"
 	pb "code.hackerspace.pl/q3k/topo/proto/control"
+
+	"code.hackerspace.pl/q3k/hspki"
 )
 
 type SwitchportState struct {
@@ -11,14 +20,57 @@
 type SwitchState struct {
 	Name  string
 	Ports []*SwitchportState
+	Stub  pb.SwitchControlClient
+}
+
+func (s *SwitchState) Fetch(ctx context.Context) error {
+	req := pb.GetPortsRequest{}
+	res, err := s.Stub.GetPorts(ctx, &req)
+	if err != nil {
+		return fmt.Errorf("GetPorts: %v", err)
+	}
+	s.Ports = make([]*SwitchportState, len(res.Ports))
+	for i, port := range res.Ports {
+		s.Ports[i] = &SwitchportState{port}
+	}
+	return nil
 }
 
 type StateManager struct {
 	Switches map[string]*SwitchState
+	Conns    map[string]*grpc.ClientConn
+	Mu       sync.RWMutex
 }
 
 func NewManager() *StateManager {
 	return &StateManager{
 		Switches: make(map[string]*SwitchState),
+		Conns:    make(map[string]*grpc.ClientConn),
 	}
 }
+
+func (s *StateManager) FetchState(ctx context.Context, conf *cpb.Config) error {
+	s.Mu.Lock()
+	defer s.Mu.Unlock()
+	for _, sw := range conf.Switch {
+		conn, ok := s.Conns[sw.ControlAddress]
+		if !ok {
+			var err error
+			conn, err = grpc.Dial(sw.ControlAddress, hspki.WithClientHSPKI())
+			if err != nil {
+				return fmt.Errorf("when connecting to switch %s: %v", sw.Name, err)
+			}
+			s.Conns[sw.ControlAddress] = conn
+		}
+
+		s.Switches[sw.Name] = &SwitchState{
+			Name: sw.Name,
+			Stub: pb.NewSwitchControlClient(conn),
+		}
+		err := s.Switches[sw.Name].Fetch(ctx)
+		if err != nil {
+			return fmt.Errorf("%q.Fetch: %v", sw.Name, err)
+		}
+	}
+	return nil
+}