On 08/19/18 02:36, Tim via users wrote:
Allegedly, on or about 18 August 2018, Ed Greshko sent:
> my DHCP server doesn't supply Domain Name
Not unusual. All sorts of different things may happen.
Clients can use their own (ignoring the fact that it mightn't work with
anything else in the network). They may or may not inform the DHCP
server of the hostname that they want to use.
DHCP servers can honour a client's requested hostname, or ignore it.
They can send their own defined hostname to the client (which might
ignore it). They can not bother to send any hostname to the client.
A client can determine their hostname by doing a reverse DNS lookup on
the IP that they get assigned. The DNS server may be supplying names
coded into it (e.g. whatever's at 192.168.1.2 will always be two.lan),
or the DHCP server may have created a DNS record providing the name
(giving a preset name to a particular MAC, whatever numerical IP
address it gets assigned today).
You can end up with clients *apparently* having two hostnames: The one
a user has given the machine, which will only work on the machine, and
nothing external to it knows what it is. And DHCP/DNS assigned ones,
which everything else on the LAN knows that machine as, but the machine
doesn't appear to know about it, itself.
Yeah, lots of different things can happen depending on what options are supplied by
the DHCP server. And if the client
implementation of RFC 2132 has properly interpreted the meaning of "should",
"must",
"may", etc. :-)
FWIW, one reason I bought the Synology router is that it implemented DHCPv6 (DHCP for
IPv6) only to later learn that
the Android developer responsible for the IPv6 stack refused to implement the client
side. I forgot his reasoning.
--
Conjecture is just a conclusion based on incomplete information. It isn't a fact.