webui: ethernet status and configuration

Status overview gains a Speed column reading ietf-interfaces:speed +
ethernet/duplex.  Interface detail page surfaces PHY type, PMD type,
supported and advertised PMDs.

Configure > Interfaces gains a per-row Ethernet panel: auto-negotiation
toggle, advertised PMDs picker, duplex tri-state, mdi-x tri-state.  Each
has a reset-to-YANG-default button.  Backend writes leaf-by-leaf via
PATCH+DELETE since a single PUT silently drops the duplex leaf.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

src/webui/internal/handlers/configure_interfaces.go

@@ -116,6 +116,13 @@ type cfgIfaceRow struct {
 	// from the WiFi interface page without bouncing to Configure >
 	// Hardware. Nil when the wifi/radio reference is empty or unknown.
 	PortRadio *ifaceRadioMirror
+	// MDIXState renders the *bool ethernet/mdi-x as a template-friendly
+	// string: "" = absent (Auto-MDIX), "true" / "false" = explicit force.
+	MDIXState     string
+	EthAutoneg    bool     // current candidate value; defaults to YANG default (true)
+	EthDuplex     string   // "" / "full" / "half"
+	EthAdvertised []string // identityref leaf-list, empty = advertise all
+	EthSupported  []string // identityref leaf-list from operational data
 }
 
 // ifaceRadioMirror is the subset of wifi-radio fields we expose on the
@@ -262,6 +269,10 @@ func (h *ConfigureInterfacesHandler) Overview(w http.ResponseWriter, r *http.Req
 			"wifi-sec-mode":      descOr(mgr, ifPath+"/infix-interfaces:wifi/access-point/security/mode", "Security mode. Open is unencrypted (insecure). For AP: wpa2-wpa3-personal is recommended for compatibility + security."),
 			"wifi-secret":        descOr(mgr, ifPath+"/infix-interfaces:wifi/access-point/security/secret", "Pre-shared key reference — a symmetric key in the keystore. 8–63 characters per the WPA spec."),
 			"wifi-hidden":        descOr(mgr, ifPath+"/infix-interfaces:wifi/access-point/hidden", "Hide the SSID from broadcast beacons. Minimal security benefit and may cause compatibility issues with some clients."),
+			"eth-autoneg":     descOr(mgr, ifPath+"/ieee802-ethernet-interface:ethernet/auto-negotiation/enable", "Enable IEEE 802.3 auto-negotiation.  When off, the link must come up via parallel detection or the forced PMD picked below."),
+			"eth-advertised":  descOr(mgr, ifPath+"/ieee802-ethernet-interface:ethernet/auto-negotiation/infix-ethernet-interface:advertised-pmd-types", "Restrict auto-negotiation to advertise only these PMD types.  Leave empty to advertise every mode the PHY supports."),
+			"eth-duplex":      descOr(mgr, ifPath+"/ieee802-ethernet-interface:ethernet/duplex", "Force half- or full-duplex.  Leave on Auto to let auto-negotiation pick.  Modern PMDs are full-duplex only."),
+			"eth-mdix":        descOr(mgr, ifPath+"/ieee802-ethernet-interface:ethernet/infix-ethernet-interface:mdi-x", "Force the copper MDI/MDI-X crossover pinout.  Leave on Auto-MDIX (default) for any link that negotiates.  Force MDI/MDI-X only when negotiation is disabled and the two ends must use opposite values."),
 		}
 		if data.Desc["ipv6-slaac"] == "" {
 			data.Desc["ipv6-slaac"] = "SLAAC (Stateless Address Autoconfiguration, RFC 4862) " +
@@ -440,7 +451,7 @@ func (h *ConfigureInterfacesHandler) Overview(w http.ResponseWriter, r *http.Req
 	}
 	sort.Strings(data.WizardAvailableRadios)
 
-	data.Interfaces = h.buildRows(ifaces)
+	data.Interfaces = h.buildRows(ifaces, operWrap.Interfaces.Interface)
 	// Populate the mirrored radio editor for WiFi interface rows from
 	// the already-fetched candidate hardware tree (no extra fetch).
 	radios := indexWifiRadios(hwCand.Hardware.Component)
@@ -1143,6 +1154,124 @@ func (h *ConfigureInterfacesHandler) DeleteIPv6(w http.ResponseWriter, r *http.R
 // field it wants preserved. Changing the `bridge` field from one name
 // to another effectively moves the port — the PUT is atomic.
 // POST /configure/interfaces/{name}/bridge-port
+// SaveEthernet writes ethernet settings via a sequence of PATCH and DELETE
+// ops rather than a single PUT.  A PUT that includes every leaf in the
+// ethernet container silently drops the duplex leaf on rousette/confd
+// (verified with curl); the per-leaf approach matches what manual PATCH
+// curls land reliably.  Tri-state fields (duplex, mdi-x) DELETE on "Auto"
+// so the candidate ends with an absent leaf, which is how the YANG model
+// expresses the default.  data-missing on DELETE is swallowed for
+// idempotency.
+// POST /configure/interfaces/{name}/ethernet
+func (h *ConfigureInterfacesHandler) SaveEthernet(w http.ResponseWriter, r *http.Request) {
+	if err := r.ParseForm(); err != nil {
+		http.Error(w, "bad request", http.StatusBadRequest)
+		return
+	}
+	ctx := r.Context()
+	name := r.PathValue("name")
+	base := ifacePath(name) + "/ieee802-ethernet-interface:ethernet"
+
+	autoneg := r.FormValue("autoneg") == "on"
+	var adv []string
+	for _, v := range r.Form["advertised"] {
+		if v != "" {
+			adv = append(adv, v)
+		}
+	}
+
+	// auto-negotiation: PUT the whole container so an empty advertised list
+	// actually clears stale entries.  DELETE on an unqualified leaf-list
+	// path fails ("requires exactly one key") under RFC 8040, so omitting
+	// the leaf-list from a container PUT is the cleanest clear.  Safe here
+	// because the container only carries enable + advertised-pmd-types
+	// (negotiation-status is deviate-not-supported in Infix).
+	an := map[string]any{"enable": autoneg}
+	if len(adv) > 0 {
+		an["infix-ethernet-interface:advertised-pmd-types"] = adv
+	}
+	body := map[string]any{"ieee802-ethernet-interface:auto-negotiation": an}
+	if err := h.RC.Put(ctx, base+"/auto-negotiation", body); err != nil {
+		log.Printf("configure interfaces %s ethernet autoneg: %v", name, err)
+		renderSaveError(w, err)
+		return
+	}
+
+	// duplex: PATCH if user picked full/half, DELETE on Auto
+	if d := r.FormValue("duplex"); d != "" {
+		body := map[string]any{
+			"ieee802-ethernet-interface:ethernet": map[string]any{"duplex": d},
+		}
+		if err := h.RC.Patch(ctx, base, body); err != nil {
+			log.Printf("configure interfaces %s ethernet duplex: %v", name, err)
+			renderSaveError(w, err)
+			return
+		}
+	} else if err := h.RC.Delete(ctx, base+"/duplex"); err != nil && !restconf.IsDataMissing(err) {
+		log.Printf("configure interfaces %s ethernet duplex delete: %v", name, err)
+		renderSaveError(w, err)
+		return
+	}
+
+	// mdi-x: only valid when autoneg is off (YANG when).  On autoneg=true
+	// or user picks Auto-MDIX, DELETE so the leaf stays absent.
+	mdix := r.FormValue("mdix")
+	if !autoneg && (mdix == "true" || mdix == "false") {
+		body := map[string]any{
+			"ieee802-ethernet-interface:ethernet": map[string]any{
+				"infix-ethernet-interface:mdi-x": mdix == "true",
+			},
+		}
+		if err := h.RC.Patch(ctx, base, body); err != nil {
+			log.Printf("configure interfaces %s ethernet mdi-x: %v", name, err)
+			renderSaveError(w, err)
+			return
+		}
+	} else if err := h.RC.Delete(ctx, base+"/infix-ethernet-interface:mdi-x"); err != nil && !restconf.IsDataMissing(err) {
+		log.Printf("configure interfaces %s ethernet mdi-x delete: %v", name, err)
+		renderSaveError(w, err)
+		return
+	}
+
+	renderSavedRedirect(w, "Ethernet saved", "/configure/interfaces")
+}
+
+// ResetEthernetAdvertised clears the advertised-pmd-types leaf-list while
+// preserving auto-negotiation/enable.  Routed off the per-row reset
+// button because the generic /configure/leaf path can't DELETE a leaf-list
+// without per-entry key predicates.
+// DELETE /configure/interfaces/{name}/ethernet/advertised
+func (h *ConfigureInterfacesHandler) ResetEthernetAdvertised(w http.ResponseWriter, r *http.Request) {
+	name := r.PathValue("name")
+	base := ifacePath(name) + "/ieee802-ethernet-interface:ethernet"
+
+	var resp struct {
+		AN struct {
+			Enable *bool `json:"enable"`
+		} `json:"ieee802-ethernet-interface:auto-negotiation"`
+	}
+	enable := true // YANG default
+	if err := h.RC.Get(r.Context(), base+"/auto-negotiation", &resp); err == nil {
+		if resp.AN.Enable != nil {
+			enable = *resp.AN.Enable
+		}
+	} else if !restconf.IsNotFound(err) {
+		log.Printf("configure interfaces %s reset advertised get: %v", name, err)
+		renderSaveError(w, err)
+		return
+	}
+
+	body := map[string]any{
+		"ieee802-ethernet-interface:auto-negotiation": map[string]any{"enable": enable},
+	}
+	if err := h.RC.Put(r.Context(), base+"/auto-negotiation", body); err != nil {
+		log.Printf("configure interfaces %s reset advertised put: %v", name, err)
+		renderSaveError(w, err)
+		return
+	}
+	renderSavedRedirect(w, "Reset to default", "/configure/interfaces")
+}
+
 func (h *ConfigureInterfacesHandler) SaveBridgePort(w http.ResponseWriter, r *http.Request) {
 	if err := r.ParseForm(); err != nil {
 		http.Error(w, "bad request", http.StatusBadRequest)
@@ -1739,7 +1868,13 @@ func (h *ConfigureInterfacesHandler) fetchAllInterfaces(ctx context.Context) ([]
 
 type membership struct{ kind, master string }
 
-func (h *ConfigureInterfacesHandler) buildRows(ifaces []ifaceJSON) []cfgIfaceRow {
+func (h *ConfigureInterfacesHandler) buildRows(ifaces []ifaceJSON, oper []ifaceJSON) []cfgIfaceRow {
+	// Index operational so each row can pull supported-pmd-types — that
+	// leaf is config false, so the candidate read doesn't carry it.
+	operByName := make(map[string]*ifaceJSON, len(oper))
+	for i := range oper {
+		operByName[oper[i].Name] = &oper[i]
+	}
 	// Build a set of current bridge/lag members for fast lookup.
 	memberOf := make(map[string]membership, len(ifaces))
 	for _, iface := range ifaces {
@@ -1793,6 +1928,24 @@ func (h *ConfigureInterfacesHandler) buildRows(ifaces []ifaceJSON) []cfgIfaceRow
 				row.WifiMode = "station"
 			}
 		}
+		row.EthAutoneg = true // YANG default when no candidate value is set
+		if iface.Ethernet != nil {
+			row.EthDuplex = iface.Ethernet.Duplex
+			if iface.Ethernet.AutoNegotiation != nil {
+				row.EthAutoneg = iface.Ethernet.AutoNegotiation.Enable
+				row.EthAdvertised = iface.Ethernet.AutoNegotiation.AdvertisedPMDs
+			}
+			if iface.Ethernet.MDIX != nil {
+				if *iface.Ethernet.MDIX {
+					row.MDIXState = "true"
+				} else {
+					row.MDIXState = "false"
+				}
+			}
+		}
+		if op := operByName[iface.Name]; op != nil && op.Ethernet != nil {
+			row.EthSupported = op.Ethernet.SupportedPMDs
+		}
 		if m, ok := memberOf[iface.Name]; ok {
 			row.MemberOf = m.master
 		}

src/webui/internal/handlers/interfaces.go

@@ -8,11 +8,14 @@ import (
 	"log"
 	"math"
 	"net/http"
+	"slices"
 	"sort"
+	"strconv"
 	"strings"
 	"sync"
 
 	"infix/webui/internal/restconf"
+	"infix/webui/internal/schema"
 )
 
 // RESTCONF JSON structures for ietf-interfaces:interfaces.
@@ -31,6 +34,9 @@ type ifaceJSON struct {
 	OperStatus  string          `json:"oper-status"`
 	PhysAddress string          `json:"phys-address"`
 	IfIndex     int             `json:"if-index"`
+	// Operational link rate from ietf-interfaces (yang:gauge64 bits/s).
+	// The same-named leaf inside the ethernet container is obsolete.
+	Speed yangInt64 `json:"speed"`
 	IPv4        *ipCfg          `json:"ietf-ip:ipv4"`
 	IPv6        *ipCfg          `json:"ietf-ip:ipv6"`
 	Statistics  *ifaceStats     `json:"statistics"`
@@ -211,10 +217,16 @@ type ifaceStats struct {
 }
 
 type ethernetJSON struct {
-	Speed           string `json:"speed"`
 	Duplex          string `json:"duplex"`
+	PhyType         string `json:"phy-type"`
+	PMDType         string `json:"pmd-type"`
+	SupportedPMDs []string `json:"infix-ethernet-interface:supported-pmd-types"`
+	// *bool because the YANG model uses absent as the Auto-MDIX signal —
+	// collapsing nil and false here would lose the tri-state.
+	MDIX            *bool `json:"infix-ethernet-interface:mdi-x"`
 	AutoNegotiation *struct {
-		Enable bool `json:"enable"`
+		Enable         bool     `json:"enable"`
+		AdvertisedPMDs []string `json:"infix-ethernet-interface:advertised-pmd-types"`
 	} `json:"auto-negotiation"`
 	Statistics *struct {
 		Frame *ethFrameStats `json:"frame"`
@@ -261,6 +273,7 @@ type ifaceEntry struct {
 	PhysAddr     string
 	Addresses    []addrEntry
 	Detail       string // extra info: wifi AP, wireguard peers, etc.
+	Link         string // ethernet speed + duplex e.g. "1 Gbps full"; empty for non-ethernet
 	RxBytes      string
 	TxBytes      string
 }
@@ -276,6 +289,7 @@ type InterfacesHandler struct {
 	DetailTemplate   *template.Template
 	CountersTemplate *template.Template
 	RC               *restconf.Client
+	Schema           *schema.Cache
 }
 
 // Overview renders the interfaces page (GET /interfaces).
@@ -454,6 +468,14 @@ func makeIfaceEntry(iface ifaceJSON, fwdSet map[string]bool) ifaceEntry {
 		PhysAddr:   iface.PhysAddress,
 	}
 
+	if prettyIfType(iface.Type) == ifTypeEthernet {
+		duplex := ""
+		if iface.Ethernet != nil {
+			duplex = iface.Ethernet.Duplex
+		}
+		e.Link = formatEthernetLink(uint64(iface.Speed), duplex)
+	}
+
 	if iface.Statistics != nil {
 		e.RxBytes = humanBytes(int64(iface.Statistics.InOctets))
 		e.TxBytes = humanBytes(int64(iface.Statistics.OutOctets))
@@ -520,6 +542,10 @@ type ifaceDetailData struct {
 	Speed            string
 	Duplex           string
 	AutoNeg          string
+	PhyType          string // e.g. "1000BASE-T"
+	PMDType          string // e.g. "1000BASE-T"
+	SupportedPMDs    []string // short names (what the PHY can do)
+	AdvertisedPMDs   []string // short names (what autoneg announces)
 	Addresses        []addrEntry
 	WiFiMode         string // "Access Point" or "Station"
 	WiFiSSID         string
@@ -533,6 +559,7 @@ type ifaceDetailData struct {
 	WGPeers          []wgPeerEntry
 	WiFiStations     []wifiStaEntry
 	ScanResults      []wifiScanEntry
+	Desc             map[string]string
 }
 
 type ifaceCounters struct {
@@ -632,15 +659,21 @@ func buildDetailData(r *http.Request, iface *ifaceJSON) ifaceDetailData {
 		}
 	}
 
+	if prettyIfType(iface.Type) == ifTypeEthernet {
+		d.Speed = formatEthernetLink(uint64(iface.Speed), "")
+	}
 	if iface.Ethernet != nil && prettyIfType(iface.Type) == ifTypeEthernet {
-		d.Speed = prettySpeed(iface.Ethernet.Speed)
 		d.Duplex = iface.Ethernet.Duplex
+		d.PhyType = ShortenPMD(iface.Ethernet.PhyType)
+		d.PMDType = ShortenPMD(iface.Ethernet.PMDType)
+		d.SupportedPMDs = shortenPMDs(iface.Ethernet.SupportedPMDs)
 		if iface.Ethernet.AutoNegotiation != nil {
 			if iface.Ethernet.AutoNegotiation.Enable {
 				d.AutoNeg = "on"
 			} else {
 				d.AutoNeg = "off"
 			}
+			d.AdvertisedPMDs = shortenPMDs(iface.Ethernet.AutoNegotiation.AdvertisedPMDs)
 		}
 		if iface.Ethernet.Statistics != nil && iface.Ethernet.Statistics.Frame != nil {
 			d.EthFrameStats = buildEthFrameStats(iface.Ethernet.Statistics.Frame)
@@ -745,10 +778,75 @@ func buildEthFrameStats(f *ethFrameStats) []kvEntry {
 	}
 }
 
-// prettySpeed converts YANG ethernet speed identities to display strings.
-func prettySpeed(s string) string {
-	if i := strings.LastIndex(s, ":"); i >= 0 {
-		s = s[i+1:]
+// ShortenPMD turns a PHY/PMD identityref into its IEEE shorthand,
+// e.g. "ieee802-ethernet-phy-type:pmd-type-1000BASE-T" → "1000BASE-T".
+// Exported so the configure-interfaces template can call it via funcmap.
+func ShortenPMD(s string) string {
+	s = schema.StripModulePrefix(s)
+	for _, prefix := range []string{"pmd-type-", "phy-type-"} {
+		if strings.HasPrefix(s, prefix) {
+			return s[len(prefix):]
+		}
+	}
+	return s
+}
+
+func shortenPMDs(pmds []string) []string {
+	if len(pmds) == 0 {
+		return nil
+	}
+	out := make([]string, len(pmds))
+	for i, p := range pmds {
+		out[i] = ShortenPMD(p)
+	}
+	// Sort by line rate so Supported and Advertised line up
+	// row-by-row in the comparison view — ethtool --json doesn't
+	// guarantee a consistent order between the two lists.
+	slices.SortStableFunc(out, func(a, b string) int {
+		return pmdSpeedMbps(a) - pmdSpeedMbps(b)
+	})
+	return out
+}
+
+// pmdSpeedMbps extracts the line rate in megabits per second from a short
+// PMD name like "10BASE-T", "2.5GBASE-T", or "100GBASE-CR4". Unknown
+// strings sort as 0.
+func pmdSpeedMbps(name string) int {
+	i := 0
+	for i < len(name) && (name[i] >= '0' && name[i] <= '9' || name[i] == '.') {
+		i++
+	}
+	if i == 0 {
+		return 0
+	}
+	n, err := strconv.ParseFloat(name[:i], 64)
+	if err != nil {
+		return 0
+	}
+	if i < len(name) && name[i] == 'G' {
+		n *= 1000
+	}
+	return int(n)
+}
+
+// formatEthernetLink renders the ietf-interfaces:speed (yang:gauge64 bits/s)
+// plus duplex as "1 Gbps full" / "100 Mbps half"; empty when speed is 0.
+func formatEthernetLink(bps uint64, duplex string) string {
+	if bps == 0 {
+		return ""
+	}
+	var s string
+	switch {
+	case bps >= 1_000_000_000:
+		gbps := float64(bps) / 1_000_000_000
+		s = strconv.FormatFloat(gbps, 'f', -1, 64) + " Gbps"
+	case bps >= 1_000_000:
+		s = strconv.FormatUint(bps/1_000_000, 10) + " Mbps"
+	default:
+		s = strconv.FormatUint(bps/1_000, 10) + " kbps"
+	}
+	if duplex != "" {
+		s += " " + duplex
 	}
 	return s
 }
@@ -851,6 +949,7 @@ func (h *InterfacesHandler) Detail(w http.ResponseWriter, r *http.Request) {
 
 	data := buildDetailData(r, iface)
 	data.PageData = newPageData(r, "interfaces", "Interface "+name)
+	data.Desc = h.fieldDescriptions()
 
 	tmplName := "iface-detail.html"
 	if r.Header.Get("HX-Request") == "true" {
@@ -862,6 +961,28 @@ func (h *InterfacesHandler) Detail(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+// fieldDescriptions returns YANG-sourced hover descriptions for the rows
+// rendered on the interface-detail page. The keys correspond to the
+// field-info template invocations in iface-detail.html.
+func (h *InterfacesHandler) fieldDescriptions() map[string]string {
+	mgr := h.Schema.Manager()
+	if mgr == nil {
+		return nil
+	}
+	ifPath := "/ietf-interfaces:interfaces/interface"
+	ethPath := ifPath + "/ieee802-ethernet-interface:ethernet"
+	return map[string]string{
+		"mtu":        schema.DescriptionOf(mgr, ifPath+"/ietf-ip:ipv4/mtu"),
+		"speed":      schema.DescriptionOf(mgr, ifPath+"/speed"),
+		"duplex":     schema.DescriptionOf(mgr, ethPath+"/duplex"),
+		"autoneg":    schema.DescriptionOf(mgr, ethPath+"/auto-negotiation/enable"),
+		"phy-type":   schema.DescriptionOf(mgr, ethPath+"/phy-type"),
+		"pmd-type":   schema.DescriptionOf(mgr, ethPath+"/pmd-type"),
+		"supported":  schema.DescriptionOf(mgr, ethPath+"/infix-ethernet-interface:supported-pmd-types"),
+		"advertised": schema.DescriptionOf(mgr, ethPath+"/auto-negotiation/infix-ethernet-interface:advertised-pmd-types"),
+	}
+}
+
 // Counters renders the counters fragment for htmx polling (GET /interfaces/{name}/counters).
 func (h *InterfacesHandler) Counters(w http.ResponseWriter, r *http.Request) {
 	name := r.PathValue("name")

src/webui/internal/restconf/errors.go

@@ -19,6 +19,15 @@ func IsNotFound(err error) bool {
 	return errors.As(err, &e) && e.StatusCode == http.StatusNotFound
 }
 
+// IsDataMissing reports whether err is a RESTCONF "data-missing" tag error
+// (RFC 8040 §7.6.2). Returned by DELETE on a leaf that is already absent.
+// Useful when the caller is explicitly trying to reach an "absent" state
+// and treats already-absent the same as just-deleted.
+func IsDataMissing(err error) bool {
+	var e *Error
+	return errors.As(err, &e) && e.Tag == "data-missing"
+}
+
 // AuthError is returned when RESTCONF rejects credentials (401/403).
 type AuthError struct {
 	Code int

src/webui/internal/server/server.go

@@ -130,7 +130,8 @@ func New(
 		return nil, err
 	}
 	ifFuncs := template.FuncMap{
-		"add": func(a, b int) int { return a + b },
+		"shortPMD": handlers.ShortenPMD,
+		"add":      func(a, b int) int { return a + b },
 		"deref": func(v any) any {
 			switch p := v.(type) {
 			case *bool:
@@ -217,6 +218,7 @@ func New(
 		DetailTemplate:   ifDetailTmpl,
 		CountersTemplate: ifCountersTmpl,
 		RC:               rc,
+		Schema:           schemaCache,
 	}
 
 	sys := &handlers.SystemHandler{
@@ -342,6 +344,8 @@ func New(
 	mux.HandleFunc("POST /configure/interfaces/{name}/ipv6/dhcp/settings",           cfgIf.SaveIPv6DHCPSettings)
 	mux.HandleFunc("POST /configure/interfaces/{name}/ipv6/dhcp/options",            cfgIf.AddIPv6DHCPOption)
 	mux.HandleFunc("DELETE /configure/interfaces/{name}/ipv6/dhcp/options/{id}",     cfgIf.DeleteIPv6DHCPOption)
+	mux.HandleFunc("POST /configure/interfaces/{name}/ethernet",                cfgIf.SaveEthernet)
+	mux.HandleFunc("DELETE /configure/interfaces/{name}/ethernet/advertised",   cfgIf.ResetEthernetAdvertised)
 	mux.HandleFunc("POST /configure/interfaces/{name}/bridge-port",      cfgIf.SaveBridgePort)
 	mux.HandleFunc("DELETE /configure/interfaces/{name}/bridge-port",    cfgIf.DeleteBridgePort)
 	mux.HandleFunc("POST /configure/interfaces/{name}/wifi",             cfgIf.SaveWifi)

src/webui/static/css/style.css

@@ -1398,6 +1398,33 @@ details[open].nav-group-top > summary.nav-group-summary-top::before {
 .eth-stats dt { color: var(--fg-muted); font-family: var(--font-mono); }
 .eth-stats dd { text-align: right; font-family: var(--font-mono); font-weight: 600; }
 
+/* Side-by-side comparison of supported vs advertised PMDs on iface-detail.
+   Equal-width columns keep the lists visually parallel even when one side
+   is empty (no auto-negotiation, or no module data yet). */
+.pmd-compare {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 1rem;
+}
+.pmd-col-head {
+  font-size: 0.7rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.06em;
+  color: var(--fg-muted);
+  margin-bottom: 0.3rem;
+}
+.pmd-list {
+  list-style: none;
+  padding: 0;
+  margin: 0;
+  font-family: var(--font-mono);
+  font-size: 0.85rem;
+}
+.pmd-list li {
+  padding: 0.1rem 0;
+}
+
 .iface-detail-header { margin-bottom: 1.5rem; border-bottom: 1px solid var(--border); padding-bottom: 1rem; }
 .iface-detail-header h2 { font-size: 1.5rem; font-weight: 600; color: var(--fg); }
 .back-link { display: inline-flex; align-items: center; margin-bottom: 0.5rem; font-size: 0.9rem; }
@@ -1547,6 +1574,69 @@ details.fw-hint[open] summary::before { transform: rotate(90deg); }
 }
 .fw-checkbox-row input[type="checkbox"] { accent-color: var(--primary); cursor: pointer; }
 
+/* Multi-select dropdown built on <details> + checkboxes so the summary
+   row looks like a native <select> trigger and the body holds the
+   checkbox list.  Native <select multiple size="1"> never renders as
+   a dropdown, hence the substitute. */
+.cfg-multi {
+  position: relative;
+  display: inline-block;
+  min-width: 14rem;
+}
+.cfg-multi-summary {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0.4rem 0.6rem;
+  background: var(--surface);
+  color: var(--fg);
+  border: 1px solid var(--border);
+  border-radius: var(--radius);
+  font-size: 0.875rem;
+  cursor: pointer;
+  list-style: none;
+  user-select: none;
+}
+.cfg-multi-summary::-webkit-details-marker { display: none; }
+.cfg-multi-summary::after {
+  content: '\25BE';
+  margin-left: 0.5rem;
+  color: var(--fg-muted);
+  transition: transform 0.15s;
+}
+details[open] > .cfg-multi-summary::after { transform: rotate(180deg); }
+details[open] > .cfg-multi-summary {
+  border-color: var(--primary);
+  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
+}
+.cfg-multi-body {
+  position: absolute;
+  top: 100%;
+  left: 0;
+  right: 0;
+  margin-top: 0.25rem;
+  background: var(--surface);
+  border: 1px solid var(--border);
+  border-radius: var(--radius);
+  padding: 0.5rem 0.75rem;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
+  z-index: 10;
+  max-height: 20rem;
+  overflow-y: auto;
+  display: flex;
+  flex-direction: column;
+  gap: 0.35rem;
+}
+.cfg-multi-item {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  font-size: 0.875rem;
+  white-space: nowrap;
+  cursor: pointer;
+}
+.cfg-multi-item input[type="checkbox"] { accent-color: var(--primary); cursor: pointer; }
+
 .fw-result {
   display: flex;
   align-items: center;

src/webui/static/js/app.js

@@ -93,8 +93,58 @@
     fwUploadInit(root);
     initRestoreCheckbox(root);
     initYangTree(root);
+    initMultiDropdown(root);
   }
 
+  // The <details>-based multi-select dropdown needs JS to behave like a
+  // real <select>: refresh the summary text when checkboxes change, and
+  // close when the user clicks outside the widget.
+  function initMultiDropdown(root) {
+    var scope = root || document;
+    scope.querySelectorAll('.cfg-multi:not([data-init])').forEach(function (det) {
+      det.dataset.init = 'true';
+      var summary = det.querySelector('.cfg-multi-summary');
+      var body = det.querySelector('.cfg-multi-body');
+      if (!summary || !body) return;
+
+      var allBox = body.querySelector('input[data-multi-all]');
+      var itemBoxes = body.querySelectorAll('input[type="checkbox"]:not([data-multi-all])');
+
+      function refreshSummary() {
+        var labels = [];
+        itemBoxes.forEach(function (cb) {
+          if (!cb.checked) return;
+          var lab = cb.closest('label');
+          labels.push(lab ? lab.textContent.trim() : cb.value);
+        });
+        summary.textContent = labels.length ? labels.join(', ') : '(All)';
+      }
+      body.addEventListener('change', function (evt) {
+        if (evt.target === allBox && allBox.checked) {
+          // (All) was just checked — clear specific selections.
+          itemBoxes.forEach(function (cb) { cb.checked = false; });
+        } else if (evt.target !== allBox && evt.target.checked && allBox) {
+          // A specific PMD was checked — uncheck (All).
+          allBox.checked = false;
+        } else if (evt.target !== allBox && allBox) {
+          // A specific PMD was unchecked — if none remain, re-check (All).
+          var anyChecked = false;
+          itemBoxes.forEach(function (cb) { if (cb.checked) anyChecked = true; });
+          if (!anyChecked) allBox.checked = true;
+        }
+        refreshSummary();
+      });
+    });
+  }
+
+  // Close any open .cfg-multi when the user clicks outside it.  Single
+  // top-level listener — cheaper than per-widget bindings.
+  document.addEventListener('click', function (evt) {
+    document.querySelectorAll('.cfg-multi[open]').forEach(function (det) {
+      if (!det.contains(evt.target)) det.removeAttribute('open');
+    });
+  });
+
   function initYangTree(scope) {
     var root = scope || document;
     // Stop <details> from toggling when clicking interactive elements inside <summary>.

src/webui/templates/pages/configure-interfaces.html

@@ -485,6 +485,102 @@
               {{end}}{{/* IsLagPort */}}
 
 
+              {{/* ── Ethernet ────────────────────────────────────────── */}}
+              {{if eq .TypeSlug "ethernet"}}
+              {{$ep := printf "%s/ieee802-ethernet-interface:ethernet" $ip}}
+              <div style="margin-top:1rem">
+                <h4 class="cfg-section-head">Ethernet</h4>
+                <form hx-post="/configure/interfaces/{{.Name}}/ethernet" hx-swap="none">
+                  <table class="info-table">
+                    <tr>
+                      <th>Auto-negotiation{{template "field-info" (index $d "eth-autoneg")}}</th>
+                      <td><label><input type="checkbox" name="autoneg" {{if .EthAutoneg}}checked{{end}}> Enabled</label></td>
+                      <td class="cfg-reset-col">
+                        <button type="button" class="btn btn-secondary btn-sm" title="Reset to YANG default"
+                                hx-delete="/configure/leaf?path={{$ep}}/auto-negotiation/enable&redirect=/configure/interfaces"
+                                hx-swap="none"
+                                hx-confirm="Reset auto-negotiation to its YANG default?">{{template "icon-reset"}}</button>
+                      </td>
+                    </tr>
+
+                    <tr>
+                      <th>Advertised speeds{{template "field-info" (index $d "eth-advertised")}}</th>
+                      <td>
+                        {{if .EthSupported}}
+                        {{$advertised := .EthAdvertised}}
+                        <details class="cfg-multi">
+                          <summary class="cfg-multi-summary">
+                            {{if $advertised}}
+                              {{range $i, $v := $advertised}}{{if $i}}, {{end}}{{shortPMD $v}}{{end}}
+                            {{else}}(All){{end}}
+                          </summary>
+                          <div class="cfg-multi-body">
+                            <label class="cfg-multi-item cfg-multi-all">
+                              <input type="checkbox" data-multi-all {{if not $advertised}}checked{{end}}>
+                              (All)
+                            </label>
+                            {{range .EthSupported}}
+                            {{$cur := .}}
+                            {{$selected := false}}
+                            {{range $advertised}}{{if eq . $cur}}{{$selected = true}}{{end}}{{end}}
+                            <label class="cfg-multi-item">
+                              <input type="checkbox" name="advertised" value="{{.}}" {{if $selected}}checked{{end}}>
+                              {{shortPMD .}}
+                            </label>
+                            {{end}}
+                          </div>
+                        </details>
+                        {{else}}
+                        <span class="text-muted">No supported-PMD data from device.</span>
+                        {{end}}
+                      </td>
+                      <td class="cfg-reset-col">
+                        <button type="button" class="btn btn-secondary btn-sm" title="Reset to YANG default"
+                                hx-delete="/configure/interfaces/{{.Name}}/ethernet/advertised"
+                                hx-swap="none"
+                                hx-confirm="Reset advertised speeds to its YANG default?">{{template "icon-reset"}}</button>
+                      </td>
+                    </tr>
+
+                    <tr>
+                      <th>Duplex{{template "field-info" (index $d "eth-duplex")}}</th>
+                      <td>
+                        <label><input type="radio" name="duplex" value="" {{if eq .EthDuplex ""}}checked{{end}}> Auto</label>
+                        <label style="margin-left:1em"><input type="radio" name="duplex" value="full" {{if eq .EthDuplex "full"}}checked{{end}}> Full</label>
+                        <label style="margin-left:1em"><input type="radio" name="duplex" value="half" {{if eq .EthDuplex "half"}}checked{{end}}> Half</label>
+                      </td>
+                      <td class="cfg-reset-col">
+                        <button type="button" class="btn btn-secondary btn-sm" title="Reset to YANG default"
+                                hx-delete="/configure/leaf?path={{$ep}}/duplex&redirect=/configure/interfaces"
+                                hx-swap="none"
+                                hx-confirm="Reset duplex to its YANG default?">{{template "icon-reset"}}</button>
+                      </td>
+                    </tr>
+
+                    <tr>
+                      <th>MDI-X{{template "field-info" (index $d "eth-mdix")}}</th>
+                      <td>
+                        <label><input type="radio" name="mdix" value="" {{if eq .MDIXState ""}}checked{{end}}> Auto-MDIX</label>
+                        <label style="margin-left:1em"><input type="radio" name="mdix" value="false" {{if eq .MDIXState "false"}}checked{{end}}> Force MDI</label>
+                        <label style="margin-left:1em"><input type="radio" name="mdix" value="true" {{if eq .MDIXState "true"}}checked{{end}}> Force MDI-X</label>
+                      </td>
+                      <td class="cfg-reset-col">
+                        <button type="button" class="btn btn-secondary btn-sm" title="Reset to YANG default"
+                                hx-delete="/configure/leaf?path={{$ep}}/infix-ethernet-interface:mdi-x&redirect=/configure/interfaces"
+                                hx-swap="none"
+                                hx-confirm="Reset MDI-X to its YANG default?">{{template "icon-reset"}}</button>
+                      </td>
+                    </tr>
+                  </table>
+                  <div class="cfg-card-footer">
+                    <button class="btn btn-primary" type="submit">Save</button>
+                    <span class="cfg-save-status"></span>
+                  </div>
+                </form>
+              </div>
+              {{end}}{{/* TypeSlug ethernet */}}
+
+
               {{/* ── WiFi interface editor ───────────────────────────── */}}
               {{/* Radio + PSK pickers mirror the Add-Interface wizard
                    pattern: each picker has Edit / + New buttons that

src/webui/templates/pages/iface-detail.html

@@ -27,10 +27,26 @@
         <td><span class="status-dot {{if .StatusUp}}status-up{{else}}status-down{{end}}"></span>{{.Status}}</td>
       </tr>
       {{if .PhysAddr}}<tr><th>MAC Address</th><td>{{.PhysAddr}}</td></tr>{{end}}
-      {{if .MTU}}<tr><th>MTU</th><td>{{.MTU}}</td></tr>{{end}}
-      {{if .Speed}}<tr><th>Speed</th><td>{{.Speed}}</td></tr>{{end}}
-      {{if .Duplex}}<tr><th>Duplex</th><td>{{.Duplex}}</td></tr>{{end}}
-      {{if .AutoNeg}}<tr><th>Auto-negotiation</th><td>{{.AutoNeg}}</td></tr>{{end}}
+      {{if .MTU}}<tr><th>MTU{{template "field-info" (index .Desc "mtu")}}</th><td>{{.MTU}}</td></tr>{{end}}
+      {{if .Speed}}<tr><th>Speed{{template "field-info" (index .Desc "speed")}}</th><td>{{.Speed}}</td></tr>{{end}}
+      {{if .Duplex}}<tr><th>Duplex{{template "field-info" (index .Desc "duplex")}}</th><td>{{.Duplex}}</td></tr>{{end}}
+      {{if .AutoNeg}}<tr><th>Auto-negotiation{{template "field-info" (index .Desc "autoneg")}}</th><td>{{.AutoNeg}}</td></tr>{{end}}
+      {{if .PhyType}}<tr><th>PHY type{{template "field-info" (index .Desc "phy-type")}}</th><td>{{.PhyType}}</td></tr>{{end}}
+      {{if .PMDType}}<tr><th>PMD type{{template "field-info" (index .Desc "pmd-type")}}</th><td>{{.PMDType}}</td></tr>{{end}}
+      {{if or .SupportedPMDs .AdvertisedPMDs}}
+      <tr><th>Link modes</th><td>
+        <div class="pmd-compare">
+          <div class="pmd-col">
+            <div class="pmd-col-head">Supported{{template "field-info" (index .Desc "supported")}}</div>
+            <ul class="pmd-list">{{range .SupportedPMDs}}<li>{{.}}</li>{{end}}</ul>
+          </div>
+          <div class="pmd-col">
+            <div class="pmd-col-head">Advertised{{template "field-info" (index .Desc "advertised")}}</div>
+            <ul class="pmd-list">{{range .AdvertisedPMDs}}<li>{{.}}</li>{{end}}</ul>
+          </div>
+        </div>
+      </td></tr>
+      {{end}}
       {{if .WiFiMode}}<tr><th>Mode</th><td>{{.WiFiMode}}</td></tr>{{end}}
       {{if .WiFiSSID}}<tr><th>SSID</th><td>{{.WiFiSSID}}</td></tr>{{end}}
       {{if .WiFiSignal}}<tr><th>Signal</th><td>{{.WiFiSignal}}</td></tr>{{end}}

src/webui/templates/pages/interfaces.html

@@ -19,6 +19,7 @@
         <th class="iface-name">Name</th>
         <th>Type</th>
         <th>Status</th>
+        <th>Speed</th>
         <th>MAC</th>
         <th>Data</th>
       </tr>
@@ -31,6 +32,7 @@
         <td class="iface-name{{if .IsMember}} iface-member-name{{end}}"><a href="/interfaces/{{.Name}}" hx-get="/interfaces/{{.Name}}" hx-target="#content" hx-push-url="true">{{.Name}}</a></td>
         <td>{{.Type}}</td>
         <td><span class="iface-status {{if .StatusUp}}iface-up{{else}}iface-down{{end}}"></span>{{.Status}}</td>
+        <td>{{.Link}}</td>
         <td>{{.PhysAddr}}</td>
         <td>{{range $i, $a := .Addresses}}{{if $i}}<br>{{end}}{{$a.Address}}{{if $a.Origin}} <span class="addr-origin">({{$a.Origin}})</span>{{end}}{{end}}{{if and .Addresses .Detail}}<br>{{end}}{{if .Detail}}<span class="data-detail">{{.Detail}}</span>{{end}}</td>
       </tr>