When using iPhone USB tethering, the connection will drop after about 5 minutes. The WebUI shows "The interface is connected but the internet can't be accessed". Unplugging and replugging the device brings the connection back but it will drop again after a few minutes.
Anecdotally, this seems to affect iPhones with USB-C ports instead of lightning ports. When tethering with an iPhone 14 Pro Max (lightning) the connection did not drop. But using an iPhone 15 Pro and an iPhone 16 Pro (both with USB-C) the connection will drop.
Noticed this behavior on both a GL-AXT1800 and GL-A1300 running firmware 4.6.4.
Potentially relevant logs:
Mon Oct 14 11:45:19 2024 daemon.notice netifd: Network device 'eth3' link is down
Mon Oct 14 11:45:19 2024 daemon.notice netifd: Interface 'tethering' has link connectivity loss
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Interface eth3.IPv6 no longer relevant for mDNS.
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Leaving mDNS multicast group on interface eth3.IPv6 with address fe80::6c3a:ffff:fed1:83dd.
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Interface eth3.IPv4 no longer relevant for mDNS.
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Leaving mDNS multicast group on interface eth3.IPv4 with address 172.20.10.2.
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Withdrawing address record for fe80::6c3a:ffff:fed1:83dd on eth3.
Mon Oct 14 11:45:19 2024 daemon.info avahi-daemon[4427]: Withdrawing address record for 172.20.10.2 on eth3.
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: SIOCGIFINDEX: No such device
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: received SIGTERM
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: unicasting a release of 172.20.10.2 to 172.20.10.1
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: sending release
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: can't bind to interface eth3: No such device
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: bindtodevice: No such device
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): udhcpc: entering released state
Mon Oct 14 11:45:19 2024 kern.info kernel: [ 2443.910237] ipheth 2-1:4.2: Apple iPhone USB Ethernet now disconnected
Mon Oct 14 11:45:19 2024 daemon.notice netifd: tethering (20879): Command failed: Permission denied
Mon Oct 14 11:45:19 2024 daemon.notice netifd: Interface 'tethering' is now down
Mon Oct 14 11:45:19 2024 daemon.notice netifd: Interface 'tethering' is disabled
Mon Oct 14 11:45:19 2024 daemon.warn dnsmasq[5158]: no servers found in /tmp/resolv.conf.d/resolv.conf.auto, will retry
Mon Oct 14 11:45:19 2024 user.notice firewall: Reloading firewall due to ifdown of tethering ()
Mon Oct 14 11:45:19 2024 kern.info kernel: [ 2444.092519] usb 2-1: reset SuperSpeed USB device number 2 using xhci-hcd
Mon Oct 14 11:45:19 2024 kern.info kernel: [ 2444.129831] ipheth 2-1:4.2: Apple iPhone USB Ethernet device attached
Mon Oct 14 11:45:19 2024 daemon.err usbmuxd[13604]: [11:45:19.832][3] Removed device 2 on location 0x20002
Mon Oct 14 11:45:19 2024 daemon.notice netifd: Interface 'tethering' is enabled
Mon Oct 14 11:45:20 2024 user.notice kmwan: config json str={ "op": 3, "data": { "cells": [ "tethering" ] } }
Mon Oct 14 11:45:20 2024 kern.warn kernel: [ 2445.174569] kmwan: Delete node:tethering