In message <[email protected]>, "Ronald F. Guilmette" writes: > > My apologies if this question might also be considered a bit > off-topic for this list. > > Is the maximum possible size of a DNS packet (just the payload part... > not including IP and UDP headers) 64k bytes? > > I have some old code which assumes that, perhaps incorrectly.
DNS UDP message size can be up to 512 bytes. RFC 103[45] EDNS UDP message size can be up to 65535 bytes less overhead but most implementations advertise a much smaller size (~4K). RFC 6891 TCP message size can be up to 65535 bytes as there is a 2 octet header specifying the size of the TCP DNS message. RFC 103[45] Mark > _______________________________________________ > Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe > from this list > > bind-users mailing list > [email protected] > https://lists.isc.org/mailman/listinfo/bind-users -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: [email protected] _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list [email protected] https://lists.isc.org/mailman/listinfo/bind-users

