[Dnsmasq-discuss] RFC 5908 - DHCPv6 NTP option 56

Kevin Darbyshire-Bryant kevin at darbyshire-bryant.me.uk
Thu Sep 10 13:55:54 BST 2015

Hi All,

I've been looking at providing NTP server addresses to my DHCPv6 clients
using dnsmasq.  2 RFCs seem applicable, Simple NTP provision RFC4075
defines option 31 and known to dnsmasq as 'sntp-server'.  RFC5908
defines a more flexible/complicated provision mechanism using option 56,
known to dnsmasq as 'ntp-server'.

RFC5908 uses sub-options to option 56 defining a choice of sub-option 1 
unicast NTP server address, sub-option 2 Multicast server address and
sub-option 3 provision of a FQDN of the NTP server.

Looking at the dnsmasq logs (I've not yet got to packet capture) and
limited understanding of the code, I'm not convinced that dnsmasq's
option 56 implementation understands the usage of sub-options.

As ever, assuming I've mis-understood something here!

Best regards,


-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4816 bytes
Desc: S/MIME Cryptographic Signature
URL: <http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/attachments/20150910/a4822714/attachment.bin>

More information about the Dnsmasq-discuss mailing list