DDNS: No start after boot

Hi, I installed a current snapshot on a RPI4, everything runs fine so far. Only DDNS worries me.

I found an ancient thread from 2018 which I do not consider to be relevant since on my last install (snapshot from 2020) DDNS was fine without manual tweaking.

Autostart is enabled (in luci webinterface and checked via "/etc/init.d/ddns enabled") but it foes not show up after booting. "logread -e ddns" returns empty also, so I assume no start attempts.

If I do "/etc/init.d/ddns start" manually it starts fine!

How could I debug what's going on there? This is my config:

config ddns 'global'
	option ddns_dateformat '%F %R'
	option ddns_loglines '250'
	option ddns_rundir '/var/run/ddns'
	option ddns_logdir '/var/log/ddns'

config service 'DomainService'
	option use_ipv6 '1'
	option update_url 'https://robot.robotdomain.de/scripts/dynamic_dns.php?zone=domain.de&zone_password=NULL&host=xyz'
	option username 'NULL'
	option use_https '1'
	option retry_unit 'seconds'
	option check_interval '7'
	option enabled '1'
	option force_unit 'minutes'
	option check_unit 'minutes'
	option domain 'NULL'
	option password 'NULL'
	option lookup_host 'xyz.domain.de'
	option cacert 'IGNORE'
	option dns_server 'pns01.robotdomain.net'
	option ip_source 'interface'
	option ip_interface 'eth1'
	option interface 'eth1'

This is a pure IPv6 setup. May be eth1 gets no IPv6 IP fast enough? But the difference is, as said, I used a snapshot until now and in this this worked fine. Which happens, that's what they are for, but how to debug further?

You could add

sleep 30
/etc/init.d/ddns restart

To you local startup script.

The ddns Implementation should deal with that, and keep trying until it get's through.

I'm actually depending on that to work, as my ISP doesn't immediately send an RA when establishing the connection (it may take up to 15 minutes to get IPv6 connectivity) - but it does work for me (at least with hurricane electric and no-ip).

Same happening to me.
Thanks for the workaround @frollic