Hi All,
I’ve been using a RUT955 at a campsite and now want to update this to a TRB500 for 5G connectivity.
The device is installed and from a laptop connected to the wireless network, I can ping IP’s and resolve DNS no problem whatsoever.
However, if I try and open a website, I get no response at all, If I put the RUT955 back in place, all works as expected and I can access websites.
I took the TRB500 back to the office and connected it to a similar setup, same problem, DNS and ping work find, but http/https access is non existant.
Annoyingly, if I connect a laptop directly to the TRB, this works fine.
I’m using TPLink Omada hardware, an ER605 for the router and EAP225 for WiFi access with an OC200 as the controller.
Equally annoying I have a vague memory from 5 years ago when I initially installed this with the RUT955 that I had the same problem, but for the life of me, I don’t recall the solution.
If anyone has any ideas or can reboot my memory for me, I would greatly appreciate it!
Good afternoon,
A few observations for your case :
Since ping and DNS resolution work, the basic IP connectivity and DNS configuration are correct. The problem is with HTTP/HTTPS traffic specifically.
Connecting a laptop directly to the TRB500 works fine, so the router itself is capable of handling web traffic correctly. This suggests the problem arises when the TRB500 is used behind your TP-Link Omada network equipment (ER605 router, EAP225 APs, OC200 controller.
Similiar issues reported from Omada environments. These have sometimes been traced to DNS settings needing to be manually configured on the routers, e.g., using Google DNS 8.8.8.8 and 8.8.4.4 rather than relying on automatic DNS from the ISP or modem.
Firmware issues on the TRB500 can also cause strange network behavior. Make sure your TRB500 firmware is fully up to date with the latest stable version from Teltonika as older versions had fixes related to firewall and network stability.
Check the TRB500 firewall and NAT settings, especially any port forwarding or DMZ rules. The latest firmware includes fixes for HTTP/HTTPS port forwarding and DMZ lease renewals.
Review VLAN and subnet configurations on your TP-Link Omada equipment. Misconfigured VLANs or routing rules can cause HTTP/HTTPS traffic to be blocked or misrouted even if ping works.
Since you recall a similar problem with the RUT955 before, it may have been resolved by explicitly setting DNS servers on the router or adjusting firewall rules to allow web traffic.
As a troubleshooting step, try setting the TRB500 to bridge mode if possible, so it acts purely as a modem, letting the ER605 handle routing and firewall. This can isolate whether the TRB500 routing/firewall is causing the issue.
Also, verify that no security or filtering features on the Omada controller or ER605 are blocking web traffic from the TRB500 subnet.
Regards,
Arturas
Thank you, switching the TRB500 into Bridge mode works, the IP is assigned to the ER605 and connectivity works as expected. Why it doesn’t work in NAT mode on the mobile data WAN I don’t know as yet.
So it’s got to be something with the TRB itself. Ideally I’d like to keep this functioning normally as I would prefer a direct VPN to the TRB itself for remote maintenance purposes.
I’ll keep digging!
Hello,
Could you please clarify your current network topology a bit further, ideally including the IP addressing scheme for each device?
Additionally, I’d recommend confirming or trying the following:
- Verifying the default route on your ER605, it should be pointing to the TRB500’s LAN IP as the primary gateway.
- For testing purposes, try lowering the MTU on the TRB500’s
mob1s1a1 interface to 1420 or 1400, because 5G mobile networks often use smaller MTU sizes, and if packets exceed this, they get fragmented or dropped silently.
- Could you confirm the first octets of the public IP address you’re receiving from your mobile ISP? It’s possible you’re being assigned a CG-NAT address, which might interfere with NAT traversal.
To clarify, if your TRB500 is in bridge mode, passing the mobile IP directly to the ER605, there shouldn’t be any NAT or TCP MSS clamping handled by the TRB500; therefore, NAT is being handled by the ER605.
Best regards,