---
title: "iPhone Mirroring Hangs on 'Connecting…' — AWDL Data Stall (27.0 Beta)"
domain: troubleshooting
category: macos
tags: [macos, iphone-mirroring, continuity, awdl, rapport, quic, tailscale, mullvad, beta, channel-validation, aimesh, quicktime, usb]
status: published
created: 2026-06-09
updated: 2026-06-14
---

# iPhone Mirroring Hangs on 'Connecting…' — AWDL Data Stall (27.0 Beta)

## Update 2026‑06‑14 — root cause refined (and what is *not* the cause)

> Re‑investigated end‑to‑end on the **same OS seed** (build `26A5353q`, unchanged). The original "AWDL data stall / nothing local was wrong" call was close but mis‑attributed the secondary causes. Corrected understanding below — **practical outcome is unchanged: no user‑side fix, wait for a new seed.**

**Refined root cause — the AWDL _bulk‑data_ path can't hold a 5 GHz channel.**
Pulled the iPhone's own logs over USB (`sudo log collect --device --last 8m --output ~/Desktop/x.logarchive`). The kernel Wi‑Fi driver (`AppleBCMWLAN`, `wlan0:com.apple.p2p.awdl0`) shows, over 8 min on infra channel 36:
- `isValidChannel … not match … channel 36 band 0x10` — **238×** (vs 32 passes): AWDL rejects the channel for the P2P group.
- `Disable Steering on Timeout` — **159×**: can't steer to a better channel.
- `isInfraRealtimePacketThresholdAllowed allowed:0` — **169/451**: bulk realtime packets blocked ~37 % of the time.

Net: the Mac's `awdl0` carries **~90 B/s** (control keepalive only; real video is hundreds of KB/s–MB/s). The feed is **starved, not corrupted** — "missing icons" = frame data that never arrived (zero decode/`kVT` errors logged).

**What is NOT the cause (each tested and ruled out):**
- **Tailscale is not a hard RF blocker.** With accept‑routes on but **no exit node**, mirroring connects. Tailscale only *intermittently* breaks the **control plane** (QUIC endpoint binding → "Connection Interrupted"); with Tailscale **off** the session establishes but the **bulk video still starves**. So the old "disable Tailscale" step lets you *connect* but does **not** fix the video. (Mechanism is control‑plane endpoint flapping, not the RF‑layer block the original note implied.)
- **Not congestion.** Router `chanim_stats` on ch36 = **90 % idle, 86 % txop, 3 % obss**; Mac link −39 dBm / −94 dBm noise. Pristine.
- **Not the channel number — the whole UNII‑1 block is AWDL‑hostile on this seed.** ch36 → starved feed (~90 B/s, glitchy). **ch44** (same 36–48 block) → **worse**: times out before media starts (`Failed to find endpoint`, `MediaContinuityKit.TaskTimeoutError`, 0 B/s). Both fail → the validator rejects the entire UNII‑1 block, not just primary 36.
- **ch149 (UNII‑3) untested.** It's the iPhone's preferred AWDL anchor and a *different* block, so it's the one channel that might work — but it's busier and the AiMesh controller resists pinning it (see infra notes). Deferred as not worth the disruption for a beta bug.

**Wired workaround (works today, no AWDL):**
iPhone Mirroring is **wireless‑only — there is no USB transport** (confirmed: cable connected throughout, every attempt still used `awdl0`). For a wired view of the screen:
> **QuickTime Player → File → New Movie Recording → ⌄ next to record → select the iPhone** = full‑rate USB‑C screen mirror (view + record). Does **not** give remote control (tap/type) — that's unique to iPhone Mirroring.

**Infra notes (RT‑AX82U, AiMesh controller):**
- Router SSH is on **port 1025** (not 22); creds in Ansible vault (`router_username` / `router_password`).
- The 5 GHz channel is **AiMesh‑coordinated** and **resists CLI changes** — `wl chanspec` / nvram `wl1_chanspec` get re‑asserted by `acsd2` + AiMesh within seconds, even after `restart_wireless`. Only setting Control Channel to an **explicit value in the Web UI** holds mesh‑wide. Left "Auto" → acsd2 picks **36** (the cleanest channel).
- Any channel change triggers a **mesh re‑sync (~1 min) that drops all Wi‑Fi**; during it MajorAir falls back to the iPhone's **USB Personal Hotspot** (`en7` / `172.20.10.x`) and won't auto‑rejoin home Wi‑Fi while the hotspot feeds it internet (manual Wi‑Fi‑menu join needed).
- **Current state: 5 GHz on ch44/80** (same clean UNII‑1 spectrum as 36; left here to avoid another re‑sync — the Deck streams identically on 44).

**Revisit checklist — when a new iOS/macOS seed ships:**
1. Confirm the seed changed: `sw_vers` BuildVersion ≠ `26A5353q` (both Mac and iPhone).
2. Tailscale **off**; iPhone on home Wi‑Fi, near the Mac, **Personal Hotspot off**.
3. Open iPhone Mirroring.
4. Measure `awdl0` RX over a few seconds — **target hundreds of KB/s** (real video), not ~90 B/s.
5. Pull the iPhone log (`log collect --device`) and check `isValidChannel` now **passes** for the infra channel.
6. If still starved → no user fix; re‑file Feedback Assistant and keep waiting.

---

## Symptom
iPhone Mirroring on the Mac sits on **"Connecting…"** forever and never shows the iPhone screen.
- Mac: **macOS 27.0 dev beta** (build 26A5353q), MajorAir
- iPhone: **Major16Pro / iPhone17,1, iOS 27.0 dev beta**, same Apple ID (maj.linux@gmail.com)

## Root cause (conclusion)
A **bug in the iPhone Mirroring beta** (both devices on the `.0` developer seeds). The connection
authenticates, the AWDL peer-to-peer link comes up, the TLS handshake starts — then **bidirectional
data stalls ~2 seconds in** and the link is torn down. Deterministic, reproduces every attempt.
**Nothing in the local configuration was wrong.** Filed via Feedback Assistant; expected to clear in
a future seed.

Two *real but secondary* network-layer issues were found and fixed along the way (see below) — they
can block mirroring independently, but were not the cause of the final 2-second stall.

## The smoking gun (unified log)
Per connection attempt the sequence is always:
```
rapportd: Session start … linkType "AWDL", error "NoError"      # link negotiated OK
iPhone Mirroring: Installing verify block for 1 authorized peer key(s)
boringssl: TLS client read_server_hello                          # iPhone DID respond
quic: path over awdl0 received event established / promoted to primary
nw_flow_connected: Transport protocol connected (socket)
… flow:connect_stalled @2.003s                                  # stalls exactly ~2s in
quic_conn_log_summary: Connection attempts: 6, RETRY received: no, PTOs: 5   # packets sent, zero ACKs
[C1.1.1 … awdl0 … failed socket-flow (unsatisfied (No network route))]      # link dropped (symptom, not cause)
```
The connection is pinned to AWDL (`allowed subtypes: wifi_awdl, prohibit fallback`), so once the
AWDL data path stalls there is no fallback and it fails. "No network route" is the *result* of the
teardown, not the trigger. The trigger is that after the initial handshake packets, **sustained
QUIC traffic over AWDL gets no ACKs** (PTOs).

## Investigation path (what was ruled out)
- **Discovery / proximity** — healthy throughout. BLE + Bonjour resolve the iPhone; `rapportd`
  sees it with good RSSI, same iCloud (`DF < MyiCloud >`), `WiFiP2P`.
- **Tailscale (full-tunnel)** — with Tailscale connected, the attempt died at "No network route"
  *before* even reaching AWDL. Cause: `RouteAll: true` (accept-routes / a `::/0` advertised route)
  installs **IPv6 default routes via `utun`** (`default → fe80::%utun0..3`) that black-hole the
  IPv6 path AWDL needs. **`tailscale down` is NOT enough** — it only sets `WantRunning=false`; the
  macOS VPN *configuration* (`scutil --nc list` showed it still `Connected`) and the system
  extension keep reasserting the routes across reboots. Must disable in **System Settings → VPN**.
- **Mullvad** — `mullvad-daemon` running; **"Local network sharing" was set to `block`**, which
  blocks LAN/AWDL/multicast. Changed to **`allow`** (`mullvad lan set allow`). Kill-switch was off.
- **macOS firewall** — off. No Little Snitch/LuLu app installed.
- **Lockdown Mode** — off (iPhone).
- **OS-version mismatch** — ruled out; both Mac and iPhone on 27.0 dev beta.
- **Device trust / re-pairing** — there is **no local pairing record on the Mac** to reset.
  `rapportd` lists the iPhone as **"PairedSys Conjectured"** = trust is *derived from the shared
  Apple ID*, not a manual pairing. Forgetting the Mac on the iPhone does not force re-setup; the
  Mac just re-derives the association from iCloud and reconnects. (App containers
  `~/Library/Containers/com.apple.ScreenContinuity` and the rapport stores held no device record;
  the "1 authorized peer key" lives in the protected system keychain.)
- **Reboots / airplane-mode toggle / Mac-side AWDL + rapportd reset** — no change.

## Secondary issues found & fixed (do these regardless)
1. **Mullvad** — set **Local network sharing = allow** (done). Required for any LAN/AWDL feature.
2. **Tailscale** — do not run **full-tunnel / accept a `::/0` route** while mirroring; it installs
   IPv6 default routes via `utun` that kill the local link. Toggle the VPN off in System Settings
   (not just `tailscale down`) if it ever needs to be fully out of the path.
3. **Orphaned Little Snitch network extension** — the app was uninstalled but its
   `at.obdev.littlesnitch.networkextension` is still `[activated enabled]`
   (`systemextensionsctl list`). Remove via **System Settings → General → Login Items &
   Extensions → Network Extensions**. A zombie filter extension with no app behind it can
   black-hole traffic.

## Status / next steps
- **No user-side fix.** Filed in Feedback Assistant.
- Debug capture saved: `~/Desktop/iPhoneMirroring-debug-20260609-0026.txt` (summary + log narrative).
  For a full report, trigger a sysdiagnose (**⌃⌥⇧⌘ + .**) right after reproducing and attach it.
- VPNs restored after session: Tailscale back up; Mullvad left disconnected with LAN sharing = allow.

## Useful diagnostic commands (for next time)
```bash
# Connection narrative
log show --last 10m --style compact --predicate \
  '(subsystem == "com.apple.MediaContinuityKit") OR (process == "iPhone Mirroring")' | tail -60
# rapport / AWDL negotiation
log show --last 5m --style compact --predicate 'process == "rapportd"' | grep -iE "AWDL|Pair|Session"
# VPN config really on? (CLI "down" lies)
scutil --nc list ; scutil --nc status "Tailscale"
# IPv6 default routes hijacked by utun?
netstat -rn -f inet6 | awk '$1=="default"{print}'
# Active system extensions (filters/VPNs)
systemextensionsctl list
# Mullvad LAN sharing
mullvad lan get
```

## Related
- `macos-mirrored-notification-alert-loop.md` (other Continuity issue)
- Hosts/VPN context: MajorTwin project doc (Tailscale tailnet, 100.x addresses)