FritzBox might have lost its LAN connection, possibly for an unknown reason. It seems unusual.
FritzBox might have lost its LAN connection, possibly for an unknown reason. It seems unusual.
Here’s a clearer version of your message:
Hello everyone! I’ve been facing some problems with my network setup. My LAN devices are connected through a series of equipment: outside fiber → Telekom modem → FritzBox 7590 (router) → about 10 meters (~33ft) of CAT5e cable → TP-Link TL-SG105 → two PCs and a wired WLAN AP. In short, I often lose my LAN connection to the router, and even when it works again, I can’t always reach the router or the internet. The quick fix is restarting the router, but I’m not sure what’s really happening.
I should note that these issues aren’t all one-time events; sometimes a solution worked, but then something changed. For example, walking past a switch in my room caused a loss of LAN connection. When I returned, the switch showed as disconnected, and the PC couldn’t connect to it. The internet came in normally, but the router didn’t respond.
I checked with the FritzBox using my phone—LAN was listed as disconnected. I changed all ports on the router and switched the switch port speeds, but the problem persisted. My PC still showed a connection, yet I couldn’t access the internet or reach the router. I tried renewing the DHCP server settings, but it didn’t respond either.
I’m at a loss and trying different fixes, like shaking things or testing with another device. The situation is confusing, and I’m not sure what’s causing it. If you can help clarify, it would be really appreciated. Thanks!
Start with removing all extra details from your post. The problem seems linked to the Ethernet cable connecting your switch and router. You mentioned testing it with a multimeter and using an LSA+ connector—how did you verify that? Clarify the testing method and what type of connector you’re talking about, like a keystone or network socket. Also, remember this isn’t a FritzBox; it’s just a router, and people might not be familiar with that brand.
It’s a brief read and I’ve shared all the details you provided. The problem is losing LAN connection to the router while still having internet access. Sometimes it happens but when it does return I can’t reach the router or the web. The router stays online and the WLAN works properly. Restarting the router resolves the issue. The LSA connector appears similar (though not identical) to what you have. I’m unsure of the exact name for this component, so I referred to it as a connector. I apologize for any confusion caused by unclear wording. I didn’t test the cable with a multimeter to measure resistance or check for current leaks, just trying to figure out interference issues. As someone familiar with wiring, I understand these matters. If you simply call it a router without more details, people might ask what model you’re using. Using its name avoids that confusion. Either I’m interpreting too much, or your tone comes across as dismissive.
I've been participating on this forum for a while, as the history indicates. People with long texts and tech-savvy individuals tend not to engage. That's why I'm sharing this point. I'm not aiming to offend; I just want to be clear. If you're unsure about the router model being discussed, it doesn't excuse the lack of views. You can still reference the model name in your post. The LSA+ coupler is something you should consider removing, regardless of whether it's causing a problem. Either use the right cable for the task or disconnect the RJ45 jacks and join them with a coupler like this one: Spoiler I'm not sure what's preventing you from restoring the Ethernet connection after a link loss, but I think it's another matter. If you don't actually experience the link loss, it wouldn't be an issue, so I'd disregard that now. For reliable Ethernet testing, a quality cable tester is highly recommended—they're affordable and save time. Edit: Also check if similar problems occur with other devices connected to the switch? What else is plugged into the switch?
I noticed the issue right away—I’ll address the coupler problem. I’ve felt uneasy since purchase, but I was too lazy. The cable tester idea is solid; I’ll investigate further.
PM or let me know if you need more help. I'm in Germany too and have dealt with those AVM ShitBoxes before—they're actually decent most of the time. Before we tackle the bigger issues, focus on fixing the simpler problems first.
I bought a budget Chinese network cable kit. It came with plugs but not the cable boots. Still priced at 17€, that’s fine. There was a short on one line, so I replaced the bad coupler and finished the job with a cable boot made from electrical tape. I’ll check if the problem returns. Appreciate your help! Hope this resolves everything.