Peplink: WAN flapping / failover not sticking

Always name the mode you configured: local outbound failover ≠ SpeedFusion Hot Failover ≠ Bonding ≠ Smoothing. Peplink SpeedFusion is bonding and/or Hot Failover and/or Smoothing and/or local outbound failover as configured — never conflate those modes. A driveway demo that “fails over” on weighted outbound priority is not the same product as a peer-backed Hot Failover or Bonding tunnel.

Related: Peplink multi-WAN guide · umrt-software /peplink/ · Starlink / Peplink dropouts · Starlink offline

Symptom → first bucket

Match what you see before you flash firmware or buy another SIM. Most “Peplink is broken” tickets on RVs land in power, RF/sky, SIM/auth, or mode truth — not a magic firmware revision.

• Disconnect every 1–5 minutes, LEDs blink WAN — start with WAN Health Check flaps or brownout power under load.
• Zoom / Teams die when cell drops; browsing recovers — local outbound-only failover, or SpeedFusion Hot Failover with a missing / unhealthy peer.
• Speed test fat, apps jittery — Bonding across Starlink + cell with latency mismatch (Mbps look good; interactive apps hurt).
• Second SIM idle forever — outbound priority policy, SIM auth, or a plan that blocks / throttles routers.
• InControl offline, LAN still up — upstream WAN dead or device reboot loop (often power / brownout again).
• UI says Bonding, no aggregate — no SpeedFusion peer, Care / feature pack missing on that SKU, or wrong profile.
• Starlink “connected,” Peplink marks WAN down — Ethernet handoff, PoE brownout, or a brittle health-check target.

Decision tree (do in order)

Work top-down. Changing SpeedFusion profiles before you prove power and RF is how driveway “fixes” die on the first mountain pass.

1) Power (most RV “mystery flaps”)

Measure voltage under load — A/C start, inverter surge, microwave kick-on. A bank that reads “fine” at idle can sag hard enough to reset cellular modems and flap WAN Health Checks. That looks like an ISP failure; it is a 12V problem.

• Router + cellular modem must ride the same chassis fused DC. Do not park the modem or antenna amp on a cigarette-lighter socket or a shared noisy tap while the chassis feed “looks clean.”
• Starlink PoE injector on its own fused path — brownout-aware. Do not share that feed with router / modem DC.
• Fuse labeled; conductors sized for path length. Exact amps: measure on site — we will not invent a single magical number for every coach.
• If dropouts line up with inverter events, meter the house bank under that same load before you chase RF. Related: 12V battery not charging · inverter / shore-power faults.

2) RF / sky (before touching Peplink policy)

Peplink cannot invent RF. A perfect Bonding profile on a null outdoor cell path still fails. Confirm sky and outdoor cell before you rewrite outbound rules.

• Outdoor cell usable on that carrier at the exterior antenna location? If the outside world is a dead zone, see weBoost install guide only for weak-but-present signal — weBoost will not invent coverage from zero (AGC manages gain; we don’t “tune gain”).
• Starlink clear sky? Trees and eaves win — Starlink RV guide · Starlink offline.
• Antenna isolation: cellular, Starlink routing, and weBoost outdoor antennas crowded on one roof corner create “firmware” tickets that are RF geometry.

3) SIM / modem auth

• Router-legal plan — many phone plans block or throttle routers. Bars with a plan block still look “up” and still flap Health Checks.
• Both modems registered; APN correct; trays labeled and seated after vibration (travel days loosen trays).
• Dual-SIM ≠ double speed. Treat the second SIM as insurance and map fill, not automatic aggregate Mbps unless you actually configured Bonding with a peer.

4) Mode truth (name it)

Open the config and write down exactly what is running. Say the mode out loud. Peplink SpeedFusion modes are bonding and/or Hot Failover and/or Smoothing, and many coaches only run local outbound failover with no SpeedFusion tunnel at all.

• Local outbound priority / weighted balance — no SpeedFusion tunnel; sessions may drop on handoff. Fine for browsing; brutal for Zoom if the primary dies mid-call.
• SpeedFusion Hot Failover — needs a peer (another Peplink, FusionHub, or SpeedFusion Connect) plus a healthy secondary. Without the peer / license path, the UI label lies.
• Bonding — peer required. Starlink + cell can hurt interactive apps even when Mbps look good (latency mismatch). Never expect automatic 2×.
• Smoothing — redundant copies across paths; burns more metered data. Useful for jitter-sensitive apps when you accept the data cost.

Entry chassis (BR1 Mini, some BR2 / Micro, B One class) may need PrimeCare / feature pack before SpeedFusion modes unlock — verify invoice / SKU before you assume Bonding is “broken.”

5) WAN Health Checks

• One brittle health-check IP = false flaps when that target blocks ICMP / HTTP or gets congested.
• Diversify checks; fix power / RF root cause instead of forever tightening thresholds.
• After any power or roof work, re-test intentional WAN kills in the driveway — kill cell, kill Starlink Ethernet, watch whether apps drop or stick, and whether the mode you named behaves like that mode.

6) Starlink Ethernet handoff

• Official Starlink Ethernet adapter or Starlink router LAN → Peplink WAN.
• Confirm link lights and that Peplink sees the WAN before blaming SpeedFusion.
• PoE path brownout = dish drops = Peplink flaps. Joint road guide: Starlink / Peplink dropouts.

7) Firmware source

Firmware and management only from manufacturer paths: peplink.com firmware downloads and InControl 2. No random mirrors, “community” flashes, or unlocked binaries from forums. Software hub (official links only): umrt-software-db.netlify.app/peplink/.

Owner self-checks (15 minutes)

1. Photo: WAN wiring, SIM carriers, fuse block, PoE injector feed.
2. Toggle each WAN off once in the driveway; watch whether apps drop or stick.
3. Note whether interactive apps suffer more than bulk downloads (Bonding latency-mismatch clue).
4. Write the configured mode name on a sticker inside the cabinet — outbound-only, Hot Failover, Bonding, or Smoothing.
5. Capture InControl / local UI screenshots of WAN Health Check status and peer status before you change anything twice.

What “works in the driveway” misses on the road

Driveway tests often skip the three things that kill multi-WAN on travel days: voltage under A/C and inverter surge, Starlink obstruction that only appears after you roll under trees, and cellular tower handoffs at highway speed. A weighted outbound failover that feels seamless parked can drop Zoom every time the primary cell tower swaps. A Bonding profile that looks great on a speed test can feel worse than single-WAN for calls when Starlink latency and cell latency disagree. Name the mode, then test the failure you actually care about — not only the Mbps number.

When to book UMRT

Book when Health Check flaps persist after power / RF checks, a SpeedFusion peer never stabilizes, the mechanical install is travel-unsafe, or you inherited unlabeled spaghetti after a prior DIY. Active corridor: MT · WY · ID · WA — case-by-case beyond. Prefer Text (616) 606-5277 · Book a Service.

Pricing teaser: Trip $75 within 30 miles then $1.50/mi; labor ~$150/hr (1 hr min / 30-min increments); diagnostic $175 applied if you proceed. Full rates: /pricing/.

Credentials: Peplink Certified Associate · weBoost Authorized Installer · Victron Professional Certified Installer · Dometic Professional Certified · Starlink install capability only (no Starlink Certified claim). No competitor bake-in as partners. This is the pages.dev mothership — not a live WordPress edit.

Honesty box

• Peplink Certified Associate — we design and diagnose multi-WAN; we name the mode that is actually configured.
• SpeedFusion = bonding and/or Hot Failover and/or Smoothing and/or local outbound failover as configured — never conflate.
• Firmware only from peplink.com / InControl — no mirrors.
• No invented aggregate Mbps, “always stays up,” or automatic 2× Bonding claims.
• No competitor routers or softwares baked in as partners.
• Starlink = install capability only — never “Starlink Certified.”
• Prefer Text (616) 606-5277. No live WordPress claim on this staging mothership page.

Related guides & pages

• /guide/peplink-multi-wan-guide/ — multi-WAN architecture
• /troubleshoot/starlink-peplink-dropouts/ — joint road dropouts
• /troubleshoot/starlink-offline/ — dish / sky / power path
• https://umrt-software-db.netlify.app/peplink/ — official Peplink links only
• /guide/starlink-rv-guide/ · /guide/weboost-install-guide/
• /wireless/ · /troubleshoot/