DHCP option 42 (defined in RFC 2132) can be used to specify multiple NTP server IPv4 addresses.
(There’s also DHCP option 4, but that’s used to specify the IP for the older RFC 868 time protocol.)
DHCPv6 has option 31 for SNTP (via deprecated RFC 4075), and option 56 for NTP (via RFC 5908).
So, that would probably be the best option: Get an NTP address from DHCP or DHCPv6, use that to set your clock, and then do whatever you need!
(Yes, it does require that you trust your DHCP source, and its NTP reference.)
DHCP option 42 (defined in RFC 2132) can be used to specify multiple NTP server IPv4 addresses.
(There’s also DHCP option 4, but that’s used to specify the IP for the older RFC 868 time protocol.)
DHCPv6 has option 31 for SNTP (via deprecated RFC 4075), and option 56 for NTP (via RFC 5908).
So, that would probably be the best option: Get an NTP address from DHCP or DHCPv6, use that to set your clock, and then do whatever you need!
(Yes, it does require that you trust your DHCP source, and its NTP reference.)