Some devices do not talk to Hermetry themselves. There are two cases:
- A gateway (for example a licensed router, or your own edge computer) collects data from field devices (Modbus, RS485, BLE and others) and sends it for them. These field devices are its child devices.
- The platform polls a box that cannot dial in, such as an SNMP agent, an IP camera or a recorder, through an endpoint.
The full documentation is in the Gateways, polled devices and remote access section. This page is a summary with links.
Child devices behind a gateway
The gateway logs in as itself, like any device, and is marked as a gateway (This device is a gateway when you add it). It reports for its children on the v1/gw/* topics:
| Topic (up) | Use |
|---|---|
v1/gw/connect | A child is present, with its type: {"device": "Meter A", "type": "lorawan-meter"} |
v1/gw/disconnect | A child is gone |
v1/gw/telemetry | Readings of one or more children |
v1/gw/attributes | Client attributes of children |
What to know:
- Hermetry creates a child the first time the gateway reports it, in the gateway’s organisation. The child’s profile comes from the
typethe gateway sends; without one, the gateway profile’s Profile of new children is used. - Children are addressed by name, unique per gateway. Renaming a child in Hermetry does not change the name the gateway uses.
- How many children a gateway may have is set by the profile’s Max children of a gateway, capped by your plan (500 when the plan sets no number) and by a platform ceiling of 1,000. Each child counts toward your device limit.
- Rate limits apply to each child and to the gateway as a whole. One gateway message is at most 64 KiB.
- When the gateway goes offline, its children go offline too.
In development: Sending commands and shared-attribute changes to child devices through their gateway is in development. See Commands to devices behind a gateway.
Read more:
- Devices behind a gateway: every topic, payload and rule
- Licensed gateways and Hermetry Edge: field protocols on licensed gateways, buffering during outages
Devices polled by the platform
A device that cannot dial in is reached by Hermetry instead. You set up an endpoint (the box: its host, settings and write-only secrets) and devices bound to it. In Devices > New device:
| Choice | For |
|---|---|
| Network device | “An SNMP agent or another box the platform polls, by its address and credentials; the connection is tested first.” |
| Camera or recorder | “By its address and password; the connection is tested first.” |
What to know:
- The host must be a public address. Private, loopback and link-local addresses are refused. Allow the poller’s fixed source addresses in your site’s firewall.
- Secrets are write-only: stored encrypted and never shown again.
- A failed poll backs off; after several failures in a row the device is shown offline.
- Each poll result counts as one message of your monthly quota.
- Polled devices use the Last seen only online rule. The device’s Connection tab shows its endpoint and Edit endpoint.
Read more:
- Protocol endpoints
- Polling devices over SNMP and SNMP templates reference
- Polling intervals, back-off and quota
- Cameras
Licensed routers
A licensed router can be all of these at once: a device itself, a gateway for field devices, and a LoRaWAN gateway. You can also open its web panel from Hermetry without a fixed IP address.
- Licensed devices
- Licensed routers as LoRaWAN gateways
- Remote access to a router’s panel
- Cellular connections and eSIM (eSIM management is in development)