Printer HP LaserJet P1505n no ethernet network (loosing connection after ~1 second)

[MiserM]

This is not a request for help, just to share a problem and my solution with the printer HP LaserJet P1505n!

tl;dr: Use direct ethernet connection (use the APIPA IPv4 address) to access the web interface and disable the IPv6 option.

Got the printer used and working perfectly via network under Windows 10 just before.

• USB printing from Windows 10 does work.
• Status page can be printed
• Plugged the printer in my home network (router: FritzBox 5530, autoconfiguring IPv4 (DHCP) and IPv6):
  • Printer showed up in router (with name and assigned IPv4)
  • No ping answer on this IPv4, no configuration web interface (HTTP) reachable at this IPv4
• Printer reset did not help.
• Upgraded firmware to 20120201 - did not help
• Still no network response to ping/web interface.
  But the printer got the IP via DHCP 🤔
  So Itried some aggressive pings (with retry timeout set to 0.1 second to hammer the target) revealed that about 18 seconds after starting the printer, the ping was answered 2..3 times (not more until next printer restart).
  In this 18s-timeslot, even the web interface could be retrieved once (and used one click each printer start - painful...).

Next try: Direct ethernet connection to printer (computer <- ethernet cable -> printer):

Connection to APIPA IP (link-local automatic IPv4) works (even via name <printer network name> or <printer network name>.local ) : both ping and the web interface are responding.
After investigation (disabling all optional features and enable them step by step), the IPv6 is the culprit:
with the IPv6 option disabled, the printer works as it should (with IPv6 enabled, it is loosing it network and is not available).