Hi all, really hoping for some help with this one. I've just moved from a UCG Ultra to a Dream Machine Pro, and have had nothing but issues with the intenet. No issues at all with the UCG.
iPhones work no issue, only our two Windows laptops.
Scenario & Setup:
- ISP: Optus NBN (Australia)
- Gateway: UniFi Dream Machine Pro Max (UDM Pro Max) on UniFi OS v5.1.31
- Switch & APs: USW-24-PoE, UniFi U7 APs
- Clients: Windows Laptops (Intel Wi-Fi)
- Context: Upgraded from a UniFi Cloud Gateway (UCG), which had zero issues on this exact Optus line and NBN modem. The WAN drops started immediately after deploying the UDM Pro Max.
The Issue: Every 30-40s, outbound WAN traffic drops (Request timed out).
Parallel ping tests confirm this is isolated strictly to the UDM's WAN connection:
ping192.168.1.1-t(UDM Gateway): 0% packet loss, rock-solid 2–5ms latency.ping1.1.1.1-t(Public Internet): Periodic timeouts matching the UniFiInternet Disconnectedalert.
What Has Been Tried So Far (Unresolved):
- Ruled Out Local LAN / Wi-Fi:
- Local pings to
192.168.1.1remain continuous without dropping during the WAN timeouts. - Disabled Wi-Fi Power Saving / SMPS on Windows laptops.
- Disabled Ping Conflict Detection on Default Network.
- Local pings to
- Network & Security Configuration:
- Disabled Smart Queues.
- Checked CyberSecure / IPS: 0 suspicious or concerning flows logged.
- DHCP Lease Time set to standard 86400s.
- WAN Interface & DNS Customization:
- Changed Custom Internet Verification (Echo) Server to
8.8.8.8(Google DNS) instead ofping.ui.com. - Forced WAN Port 9 Auto-Negotiation to 1 Gbps FDX (Link shows GbE active).
- Set MSS Clamping to Custom (
1452).
- Changed Custom Internet Verification (Echo) Server to
- Power Cycles & Hardware Resets:
- Performed multiple full power cycles on both the UDM Pro Max and Optus NBN box (including 5+ minute shutoffs to clear ARP/DHCP lease tables).
- Executed a hard reset on the UDM Pro Max.
No idea what else to try, so frustrating.
Source: r/Ubiquiti · by /u/DinoF40