UDP QUIC protocol broken from time to time

[kapouer]

Hi,

using openwrt 23.05.2 + uqmi_2022-11-29-0.11_mipsel_24kc.ipk on a mr6400v5.

From time to time, either after a long time, or after a reboot, access to some (not all) quic-enabled websites fail with a "http refused stream error" or similar. Typically, mail.google.com. I suppose something's wrong with UDP and when the IP of the 4G network changes ? Rebooting the router restores the situation, but then again, it might require more than one reboot. I've enabled uqmi_d, and installed uqmi_sms.sh and uqmi_led.sh (changing a bit the default values).

The network config is

config interface '4G'
    option proto 'qmi'
    option device '/dev/cdc-wdm0'
    option auth 'none'
    option pdptype 'ipv4v6'
    option default_profile '1'
    option peerdns '0'
    list dns '1.1.1.1'
    option ipv6 '1'

and the firewall config is

config zone
    option name 'wan'
    option input 'DROP'
    option output 'ACCEPT'
    option forward 'DROP'
    option masq '1'
    option mtu_fix '1'
    list network 'wan'
    list network 'wan6'
    list network '4G'
    option auto_helper '0'

Storage, memory, connections count, load average... all look normal.

When the problem happens, there is nothing different in the system or kernel logs. Also the problem appears to happen more often if I install and setup the box so that it can be accessed as wireguard peer (the router itself, in its own zone). But since that test I've reflashed to a pristine install without wireguard config.

Any hint ?

[kapouer]

I have played a lot with the config - using only luci - and now I can't reproduce. I suspect either one of those two fixed it:

• the uqmi network config needed option mtu '1420'
• or, I didn't remove the wan/wan6 interfaces, (which i did now) in favor of a single uqmi interface