I have confirmed this behaviour if Google NTP is set as the time server in Controller (Global > Controller Settings) Try changing this to any other NTP server or "Auto" then doing a reboot of...

@jra11500 Update: UK pool NTP servers work normally. Cloudflare NTP works normally Internal NTP works normally Google NTP (time.google.com) does cause switch disconnection - they go "Configuring" for...

@jra11500 Are you using the gateway as DNS proxy/cache? and what DNS server is set in the management vlan interface of the switches?

@Yann77 All manufacturers will EOL products and cease supporting them with updates, this is not limited to TP-Link at all.

@Mnetnet Use the Boot console method to factory reset it, there is a guide in the knowledge base here https://support.omadanetworks.com/en/document/13065/ If this doesnt work it may be a faulty unit

@B_Star No current way to do this, and i doubt it is all that feasible since the controller, other than the portal TCP ports itself, is likely very highly isolated form non-management vlans in most...