# Gateway and connection statuses: what they mean and what to do

Statuses show under **Integrations**, on the **Gateways** tab: the gateway has its own row, and so does each connection. A connection shows the last thing the gateway said about it, so it is fixed at the site.

## Gateway link

| Status | What it means | What to do |
|---|---|---|
| **Online** | the gateway comes online regularly | nothing |
| **Offline, last seen …** | the gateway has been silent too long | check that the service or container is running, that there is outbound access to 443 and that the proxy does not ask for a sign-in. If the service is running, data piles up on the gateway's disk and arrives later |
| **Status unknown** | the cloud cannot read the gateway's state right now | wait and reload the page; nothing to do at the site |
| **Incompatible version** | the cloud no longer accepts this gateway version. The gateway knocks but sends no data | a Windows gateway with automatic updates updates itself once a new build is out. Otherwise install the current build at the site. Meanwhile data piles up on its disk |
| **Update to … did not install** | the new version did not come up, and the service went back to the previous one | the gateway keeps running on the previous version. The same version is not offered to it again; the next one will be |

## Gateway buffer

| Status | What it means | What to do |
|---|---|---|
| **Waiting to be sent to the cloud, batches: …** | data has piled up and is not yet accepted by the cloud | nothing if the number falls. If it grows, check outbound access and the proxy |
| **Evicted by the buffer, samples: …** | the buffer ran out of space and the oldest samples were evicted: there is a hole in the history | restore the link. If outages run long, raise `buffer_max_mb` in the [settings file](/help/equipment-gateway) |
| **Not accepted, batches in quarantine: …** | the cloud refused these batches; the gateway set them aside and does not send them again | [write to us](/help/contacts) with the gateway name |

## Connection

| Status | What it means | What to do |
|---|---|---|
| **No gateway** | the connection has no gateway assigned | choose a gateway in the connection row |
| **Waiting for connection status** | a gateway is assigned but has not reported on the connection yet | wait for the gateway to come online |
| **Connecting** | the gateway is trying to connect to the equipment | wait. If the status does not change, see the reason below |
| **Connected, no values yet** | the link to the equipment is up, no values have arrived yet | check that tags are set and the source updates them |
| **Reading, tags: …** | data is flowing | nothing |
| **Reading … of …** | some tags have no value | the tags and the reason are named under the status: **no such address**, **the device did not answer**, **not allowed to read** and others. Fix the tag address or the rights on the source |
| **Gateway offline** | the connection's gateway is silent | see Gateway link above |
| **Gateway needs an update**, **Gateway can't read the protocol** | this gateway version does not know the protocol | update the gateway or choose another gateway for the connection |
| **Gateway platform unsupported** | the protocol runs only in a gateway on Windows (OPC DA, Mitsubishi CNC) | choose a gateway on Windows for the connection |
| **Closed on a critical infrastructure site**, **Site closed** | the cloud does not read this connection because of the critical infrastructure answer | see [critical infrastructure](/help/equipment-security) |
| **Catalog incomplete: …** | the source browse hit a limit | narrow the connection to the part of the tree or the topics you need |

## The reason for Not reading

| Reason | What to check |
|---|---|
| **System unavailable** | the equipment address and port, whether it is reachable from the gateway server, the firewall rules on the plant network |
| **Login rejected** | the credentials in the connection card on the Services tab |
| **Access refused** | the rights of that account on the source |
| **Server certificate not trusted** | put the OPC UA server certificate into the gateway's trusted list, more in [protocols](/help/equipment-protocols) |
| **Protocol error** | that it is this protocol answering at the address, its version and connection mode |
| **Invalid connection settings** | the connection fields. If the settings file has `equipment_hosts`, the connection address must be in the list |
| **System busy** | the source answered that it is busy: wait, or lower the poll rate and the number of connections to it |
| **Gateway limit exceeded** | more values arrive than the gateway can take in: narrow the tag set or widen the deadband |