A firmware update failed
The gateway doesn't report whether an update worked. A failed update shows up as the firmware version not changing: a few minutes after you sent it, the gateway's card still shows the old version.
Find out why
Open the gateway's page and start Live Logs (the System category is always on). Once the
5-minute update window has passed, send the update again from the Gateways page and watch.
A failed attempt shows OTA update requested -> <version> followed by one of these:
OTA fetch failed: <code>— the download didn't start. A negative code means the gateway couldn't reach the update server. An HTTP code such as404means the server didn't have that build.OTA error: <code>— the download started but didn't finish or didn't check out, usually because the connection dropped part-way.- Nothing after it — the gateway couldn't begin writing the update. Contact support.
If the stream stops and the gateway reboots instead, the update went through: check its version once it's back. If no line appears at all, the gateway didn't receive the request (it was offline or not connected). The same lines appear in the mobile app's diagnostics snapshot.
Fix it
- Online — the gateway must be online when you send the update. An offline gateway never receives it, and the request isn't kept for later.
- Connectivity — the gateway needs a steady connection for the whole download; weak Wi-Fi
(
link/weak) can interrupt it. - Power — keep the gateway powered throughout; don't unplug it mid-update.
- Wait, then retry — for up to 5 minutes after an update is sent, Synacl refuses another one (and Restart, Resend config and Reset config). After that, start the OTA update again.
What a retry can and can't fix
If the update fails before the gateway switches to the new firmware (the download stops, the connection or power drops, or the file doesn't check out), nothing changes. The gateway keeps running its current firmware without rebooting, and retrying is safe.
Once the new firmware has downloaded and checked out, the gateway switches to it and reboots. The new firmware is accepted as soon as it starts, and there's no automatic return to the old one. If a new build starts but can't get back online (for example, it can't connect to Wi-Fi or Synacl), it stays installed and can't be updated remotely. Recover the gateway with Flash via USB on its page, in Chrome or Edge: see flash an ESP32. Re-flashing keeps its Wi-Fi and account settings.