My ISP doesn’t offer IPv6 so I’m running a HE.net 6to4 tunnel and dual-stacking. My IP address is dynamic and my ISP uses PPPoE and both of these make maintaining a SIT tunnel 24/7 challenging.
Every time my IP changes it means needing to “set interfaces tunnel tun0 source-address x.x.x.x”
Initially thought of creating a python script configured via cron to check and update the tunnel IP automatically. Then wondered if perhaps it could be done through VyOS directly.
After removing the built-in checks, I was able to use the source-interface option with a pppoe device in lieu of source-address … it works up to the point of an address change → something would need to be added to re-establish the tunnel upon changing IP.
How are others solving this problem today whether in VyOS or elsewhere?
PROGRESS
No tunnel:
$ show interfaces tunnel
Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
Interface IP Address S/L Description
--------- ---------- --- -----------
Configure tunnel w. pppoe0 source-interface:
set interfaces tunnel tun0 address '2001:470:x:x::x/64'
set interfaces tunnel tun0 description 'HE.NET IPv6 Tunnel'
set interfaces tunnel tun0 encapsulation 'sit'
set interfaces tunnel tun0 remote '216.66.x.x'
set interfaces tunnel tun0 source-interface 'pppoe0'
set protocols static route6 '::/0' interface 'tun0'
$ show interfaces tunnel
Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
Interface IP Address S/L Description
--------- ---------- --- -----------
tun0 2001:470:x:x::x/64 u/u HE.NET IPv6 Tunnel
Verify connectivity:
$ ping google.com
PING google.com(yul02s05-in-x0e.1e100.net (2607:f8b0:4020:805::200e)) 56 data bytes
64 bytes from yul02s05-in-x0e.1e100.net (2607:f8b0:4020:805::200e): icmp_seq=1 ttl=120 time=16.4 ms
64 bytes from yul02s05-in-x0e.1e100.net (2607:f8b0:4020:805::200e): icmp_seq=2 ttl=120 time=16.6 ms
$ ip tunnel show
sit0: ipv6/ip remote any local any ttl 64 nopmtudisc 6rd-prefix 2002::/16
tun0: ipv6/ip remote 216.66.x.x local any dev pppoe0 ttl 64 tos inherit 6rd-prefix 2002::/16
** Force ip change on modem **
$ ping google.com
PING google.com(yul02s05-in-x0e.1e100.net (2607:f8b0:4020:805::200e)) 56 data bytes
From tunnelxxxxx.tor1.ipv6.he.net (2001:470:x:x::x) icmp_seq=1 Destination unreachable: Address unreachable
At this point, doing a delete interfaces tunnel tun0 and then setting it all back up again will restore IPv6 connectivity.
