Issues with IPv4v6 and IPv6 on openwrt with a Quectel EG06-E

[Bjørn Mork]

Aleksander Morgado <aleksander at aleksander.es> writes:

> Will have to continue investigating, but I believe the
> IPv6/IPv4v6 support in the MM protocol handler is good enough now to
> be sent to openwrt packages for review :D

Definitely.


Off Topic:

OpenWrt has lots of hidden features I really like.

I wanted to use this new and fancy LTE connection as a remote management
backup link to my network.  But this OpenWrt router already has an
external link with a default route, and I wanted to keep that.  So I
imagined I had to create a new routing table and a "good enough" traffic
matching policy rule.  The last part seemed somewhat difficult since I
didn't have much else than a dynamically allocated address to match on,
and this address could be allocated from multiple prefixes.

But OpenWrt comes to the rescue: Simply adding

        option ip4table '42'

to my 'mm' interface was enough. That's all! This not only created the
associated routes in table 42 as expected, but also automatically set up
sane rules using that table:

root at wrt1900ac-1:~# ip rule
0:      from all lookup local
10000:  from 46.66.174.155 lookup 42
20000:  from all to 46.66.174.155/29 lookup 42
32766:  from all lookup main
32767:  from all lookup default
90007:  from all iif lo lookup 42

root at wrt1900ac-1:~# ip route show table 42
default via 46.66.174.156 dev wwan0 proto static src 46.66.174.155 
46.66.174.152/29 dev wwan0 proto static scope link 

root at wrt1900ac-1:~# ip addr show dev wwan0
7: wwan0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000
    link/none 
    inet 46.66.174.155/29 brd 46.66.174.159 scope global wwan0
       valid_lft forever preferred_lft forever
    inet6 fe80::e1eb:aead:72ac:df81/64 scope link stable-privacy 
       valid_lft forever preferred_lft forever



(No dual-stack here unfortunately - AFAIK all our IPv6 enabled APNs are
"protected" by a firewall, making outside access impossible).


Bjørn