Key Takeaways
- Barge dual-SIM is lock vs quay: slot A for lock holds, slot B for quay ETAs.
- Barge last-four in SMS is enough. Do not put lock PINs or release codes in the same body.
- Keep broker OTP off the tablet that dumps lock-cut notices.
- Service pricing is devices plus SMS send volume. You bring the Android phone and operator credit.
- Free is 1 device, 300 SMS lifetime, 300 contacts. Developer is 25,000 SMS per year.
- Re-map slots after every reboot. A swapped SIM sends lock holds to the quay corridor.
Summary
Logistics dual-SIM in scenario 699 is inland barge and lock routing: lock holds, convoy windows, quay ETAs. Unlike depot city ETAs, last-mile, reverse logistics, cold-chain, air-cargo, ocean gate, rail, customs, DG yards, pick-waves, or PUDO lockers, this map is the river.
Service pricing is devices plus SMS send volume. You bring the Android phone and operator SMS credit. Free is 1 device, 300 SMS lifetime, 300 contacts. Developer is 25,000 SMS per year. Starter, Professional, and Business list Unlimited SMS as platform send volume; devices and airtime stay metered.
A lock PIN in the same SMS as a barge last-four is a leak you scheduled. Route the hold. Keep the code in the portal.
Key takeaways
- Barge dual-SIM is lock vs quay: slot A for lock holds, slot B for quay ETAs.
- Barge last-four in SMS is enough. Do not put lock PINs or release codes in the same body.
- Keep broker OTP off the tablet that dumps lock-cut notices.
- Service pricing is devices plus SMS send volume. You bring the Android phone and operator credit.
- Free is 1 device, 300 SMS lifetime, 300 contacts. Developer is 25,000 SMS per year.
- Re-map slots after every reboot. A swapped SIM sends lock holds to the quay corridor.
Related reading
Start from multi-device and dual SIM routing, pair in the device setup guide, confirm fields in SMS API documentation, and review CCNR inland-navigation notes.
Context
Quay desks land here after a reboot swapped slots and lock keepers got a quay-ETA template with a PIN leftover from a test. Broker OTP cannot share that burst.
Core scenario guidance
Pin slot A to lock events and slot B to quay ETAs. Re-pair after reboot. Never put lock PINs in SMS. Isolate OTP. Cap retries per lock event.
| Event | Slot | Fail closed |
|---|---|---|
| Lock hold | A · river plan | Quay SIM after reboot |
| Quay ETA | B · port plan | Same body as lock PIN |
| Release code | Portal only | SMS + barge last-four |
| Broker OTP | Separate device | Same tablet as lock-cut |
Canary both slots after OS updates. MCP wraps REST. Developer Center owns fields.
Cost and ownership
Two SIMs still count as one device if they share a handset — plus volume plus two airtime bills. Developer is 25,000 SMS per year. Free (1 / 300 / 300) proves pairing, not a lock.
Operations
Daily last-seen, battery, slot map, DLR by reach. After SIM reseat, one staff hold and one quay ETA. On-call before unattended lock-cut nights.
Security and compliance
Lock events reveal cargo movement. Encrypt at rest. Rotate keys. Never log lock PINs. Verify webhooks if a river system fires the SMS.
Decision guide
Ship when slot map, PIN isolation, and spare exist. Delay if reboot remap is untested. If zero phone ops is mandatory, evaluate CPaaS for that slice.
Checklist
- Slot A/B documented.
- No lock PIN in SMS.
- OTP isolated.
- Reboot remap drill.
- Spare paired.
Next steps
Return to Android SMS gateway API, compare device and SMS volume pricing, open device setup, and confirm APIs in SMS API documentation.
Deep dive: production hardening
Dual-SIM routing fails when slot maps drift after reboot. Battery exemptions dominate overnight lockhouses. OEM killers look like TOS outages.
Deep dive: scaling and failure modes
Scale is lock events, not one blast to every barge. Never claim unlimited free cloud SMS credits with no device or volume meter.
Deep dive: integration discipline
Developer Center owns live API parameters. Persist lock event id and slot. MCP is a REST wrapper. If zero phone ops is mandatory, evaluate CPaaS. You bring the Android phone and operator credit.
Related product pages
Jump to the live product docs for this topic—not another long-form article.
- multi-device and dual SIM routingCapacity and failover
- transactional SMS for orders and alertsEvent-driven messages
- SMS delivery reports (DLR)Delivery status tracking
- SMS API documentationLive endpoint reference
