Flint 2 4.9.1 – kmwan reports WAN offline when IPv4 uses MAP-T (wan6_4), causing flashing blue LED

Router
1

I have a Flint 2 (GL-MT6000) running firmware 4.9.1:

/etc/glversion: 4.9.1
OpenWrt 21.02-SNAPSHOT r15812+1092-46b6ee7ffc
Kernel 5.4.238

I am using the router directly on a Sky UK FTTP connection which is provisioned using MAP-T. MAP-T itself is working correctly using OpenWrt's map/nat46 support.

The problem is that GL.iNet's kmwan subsystem reports the Ethernet WAN as offline even though both IPv4 and IPv6 Internet connectivity are working. This also causes the front LED to continuously flash blue rather than show the normal steady white online indication.

With MAP-T established, the relevant interfaces/routes look like:

wan:
  DHCPv4 address: 100.124.1.238/18
  gateway: 100.124.0.1

wan6:
  DHCPv6-PD: working
  MAP-T parameters supplied by DHCPv6

wan6_4:
  dynamic OpenWrt MAP interface

map-wan6_4:
  MAP-T L3 device

IPv4 routing:
  default dev map-wan6_4 proto static scope link
  default via 100.124.0.1 dev eth1 proto static src 100.124.1.238 metric 10

IPv4 through MAP-T works correctly. For example, the router and downstream clients have normal IPv4 Internet connectivity, and the externally visible MAP-T IPv4 address is 2.121.132.16. Native IPv6 also works correctly.

However:

# cat /proc/gl-kmwan/config
wan:offline

The current kmwan configuration includes:

kmwan.wan.interface='wan'
kmwan.wan.track_mode='force'
kmwan.wan.addr_type='4'
kmwan.wan.check='1'
kmwan.wan.tracks='ping,1.1.1.1' 'ping,8.8.8.8' ...

This appears to be because kmwan monitors the logical wan interface/device, whereas with MAP-T the usable IPv4 Internet path is the dynamically created wan6_4 / map-wan6_4 path. The IPv4 address on wan is only the 100.64.0.0/10 MAP-T/bootstrap address.

This also explains the LED behaviour. /usr/bin/gl_led checks /proc/gl-kmwan/config for an online entry. Because it sees only wan:offline, it calls offline_led_display().

For the MT6000, offline_led_display() does:

echo 0 > /sys/class/leds/white:system/brightness
echo timer > /sys/class/leds/blue:run/trigger

whereas online_led_display() disables the blue LED and enables the white LED.

The observed LED state consequently is:

blue:run      trigger = timer
white:system  off

So the LED behaviour appears to be a consequence of kmwan not recognising the dynamic MAP-T IPv4 path rather than an actual loss of Internet connectivity.

The MAP-T configuration has also been tested across a complete Flint 2 reboot. The DHCPv4 bootstrap, DHCPv6-PD, dynamic wan6_4 interface and map-wan6_4 device are recreated automatically, and both IPv4 and IPv6 connectivity work afterwards, while kmwan continues to report wan:offline.

Is there a supported way in firmware 4.9.1 to make kmwan recognise a MAP-T IPv4 path such as wan6_4/map-wan6_4 as the effective IPv4 WAN?

I don't want simply to change kmwan.wan.interface to wan6_4, because kmwan also participates in route metrics/failover and wan6_4 is a dynamically generated interface. Likewise, I'd prefer not to patch /usr/bin/gl_led merely to hide the symptom.

If MAP-T isn't currently accounted for by kmwan, could support for a dynamic MAP-T IPv4 interface be added so that WAN health status, Multi-WAN and the front LED reflect the actual Internet state?

I can provide the MAP rule, ifstatus output, kmwan configuration and additional diagnostics if useful.

4

Hi,

Thank you for the detailed information.

To help us reproduce the issue more accurately, could you please send us the following outputs via private message?

cat /tmp/map-wan6_4.rules
ifstatus wan6
ifstatus wan6_4

This information will help us further verify your current MAP-T configuration and interface status, and allow us to reproduce a similar environment locally for further testing.

Thank you for your assistance and support.

6

These outputs contain publicly routable IPv4/IPv6 addressing. Since they were requested privately, please edit the public post to redact those addresses and send the original output to charles2 by clicking their avatar and selecting Message. Continue the technical follow-up in that private message so the diagnostic details remain together.

This reply was generated by AI. Please verify its accuracy.

GL.iNet Technical Support reviews and responds to relevant threads on business days. Please allow time for a staff response.

7

Hello,

i’ve just got SKY FFT contract and facing similar issues.

I have a Flint 3 and I've tried to configure the map-t in several ways. The best I could manage to achieve is connecting but only in IPv6, making the MAP-T not actually working. Sorry if I use this thread but it might be correlated and we might improve this comparability for everybody.

Let me know if I could send you my configs too in private or else what we can check here.

Thanks

8

Your symptom is different from the original report: there MAP-T IPv4 works and only kmwan misreports it, while your MAP-T IPv4 path is not working. Please open a separate topic and include your exact Flint 3 firmware version.

To determine whether Sky supplied a MAP rule and whether the dynamic interface was created, include redacted output from ifstatus wan6 and ifstatus wan6_4, and state whether /tmp/map-wan6_4.rules exists. Do not publish routable addresses or prefixes; if charles2 requests the complete output, send it by clicking their avatar and selecting Message.

This reply was generated by AI. Please verify its accuracy.

GL.iNet Technical Support reviews and responds to relevant threads on business days. Please allow time for a staff response.