I have been using OpenWrt for over two years (since 17.04) on my LinkSys WRT1200AC router, and am currently running 19.07.4 r11208-ce6496d796.
My ISP is IPv4 only and I like using IPv6 so have installed the 6in4 package and use a Hurricane Electric tunnel for IPv6 traffic. I have been using this setup for over two years without any issues.
Since Tuesday my WAN IPv4 access has been essentially broken - ping requests timing out, no access to IPv4-only web sites. This appeared to start gradually from about 1:20pm on Tuesday 1st December. At the same time, IPv4 on my LAN continued to work as normal, and IPv6 both on LAN on WAN (via the HE tunnel) work as normal.
WAN IPv4 obviously isn't completely broken as the HE tunnel is carrying traffic (such as this message). Also, I run an email server and a web server on my LAN and they are serving requests just fine. This issue appears to be affecting outbound IPv4 traffic only (not that that explains the HE tunnel connecting okay).
I upgraded OpenWrt in November (on the 14th) from 17.04 and things worked after the upgrade as normal. I haven't changed any settings in OpenWrt since 20th November, so am a bit flummoxed as to what is going on.
I have copied network config below. My ISP requires vlan tagging (vid 913):
config interface 'loopback' option ifname 'lo' option proto 'static' option ipaddr '127.0.0.1' option netmask '255.0.0.0' config globals 'globals' config interface 'lan' option type 'bridge' option ifname 'eth0.1' option proto 'static' option netmask '255.255.255.0' option ip6assign '64' option ipaddr '10.0.8.1' config interface 'wan' option proto 'static' option netmask '255.255.255.248' option ipaddr '22.214.171.124' option gateway '126.96.36.199' option ifname 'eth1.913' option dns '188.8.131.52' config interface 'wan6' option proto '6in4' option peeraddr '184.108.40.206' list ip6prefix '2001:470:1f09:45e::/64' option ip6addr '2001:470:1f08:45e::2/64' config switch option name 'switch0' option reset '1' option enable_vlan '1' config switch_vlan option device 'switch0' option vlan '1' option ports '5t 3 2 1 0' option vid '1' config switch_vlan option device 'switch0' option vlan '2' option ports '6t 4t' option vid '913'
I would be grateful for ideas regarding what has gone adrift.