Looking at the git master branch, it looks like Pali Rohár is actively
working in this space:
https://github.com/paulusmack/ppp/commits/master
Well, I'll give a look to find what's wrong.
Just a quick follow up to say that it is all working fine after I
upgraded to version 2.4.9 of pppd.
I had initially been using version 2.4.7, that came with Raspberry Pi OS
(buster).
I had also been testing using git master of the ppp repo on the 'client'.
But I hadn't tried upgrading the 'server' (the peer configured with the
interface identifiers).
After upgrading to 2.4.9 on the 'server' it works perfectly - even with
an older version of pppd on the 'client'.
I haven't tracked down the commit that fixed it but I guess it was
something to do with failing to Nack the random interface identifier
sent by the peer.
Thank you for your help and thoughts on the issue.
nick.
|pppd file ./ppp-options ipv6cp-accept-local /dev/ttyAMA0 115200 using
channel 368 Using interface ppp0 Connect: ppp0 <--> /dev/ttyAMA0 sent
[LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0x7f793cbe>] rcvd [LCP ConfReq
id=0xb <asyncmap 0x0> <magic 0xecde7250>] sent [LCP ConfAck id=0xb
<asyncmap 0x0> <magic 0xecde7250>] rcvd [LCP ConfReq id=0xb <asyncmap
0x0> <magic 0xecde7250>] sent [LCP ConfAck id=0xb <asyncmap 0x0> <magic
0xecde7250>] rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0x7f793cbe>]
sent [LCP EchoReq id=0x0 magic=0x7f793cbe] sent [IPV6CP ConfReq id=0x1
<addr fe80::0dfd:3c3b:e130:91ce>] rcvd [LCP EchoReq id=0x0
magic=0xecde7250] sent [LCP EchoRep id=0x0 magic=0x7f793cbe] rcvd [LCP
EchoRep id=0x0 magic=0xecde7250] rcvd [IPV6CP ConfReq id=0xb <addr
fe80::0000:0000:0000:0001>] sent [IPV6CP ConfAck id=0xb <addr
fe80::0000:0000:0000:0001>] rcvd [IPV6CP ConfNak id=0x1 <addr
fe80::0000:0000:0000:0002>] sent [IPV6CP ConfReq id=0x2 <addr
fe80::0000:0000:0000:0002>] rcvd [IPV6CP ConfAck id=0x2 <addr
fe80::0000:0000:0000:0002>] local LL address fe80::0000:0000:0000:0002
remote LL address fe80::0000:0000:0000:0001 Script /etc/ppp/ipv6-up
started (pid 7049) Script /etc/ppp/ipv6-up finished (pid 7049), status =
0x0 |