About Names??

[Kevin Darcy]

Mark Lo wrote:

> Hi,
>
>     I would like to know that the difference between my machine name and
> my hostname.

Those terms have different meanings in different contexts, so it's not an
easy one to answer. If you're asking, "does the name by which my machine
knows itself have to be same as the name by which other machines know
it?" then the answer is definitely "no". But it tends to make life easier
for many applications. Mail, for instance, tends to work better if the
"internal" and "external" -- or, if you prefer, "local" and "global" --
names are the same.

> And also, if I have a machine which is called
> "mark1.3dsources.com" by (using hostname command to find it out )and my
> dns server is located on this machine,  as a theory, do i have to assign
> my dns server name as the machine name which is called
> "mark1.3dsources.com"???

For the reasons above, I'd say the answer is "no".

>  And also, how about the IP address, if my computer's IP address is
> 202.85.156.23 (thus, assigning the IP to the NIC), then the dns server
> is in this machine, (the same as above) , my question is that does my
> DNS server's IP address has to be the same as the machine's IP address
> (the NIC's IP address)???

When you say "my DNS server's IP address" do you mean the address on which
your DNS server listens for requests? You can have a nameserver listen only
on the "loopback" address, which is not associated with any NIC. Or, did
you mean something else? There wouldn't be much use for a nameserver which
listened on an address that *nothing* could get to. If you're asking
whether you can run a nameserver whose IP address does not appear anywhere
in the DNS namespace, then you can certainly do this, but if you want that
nameserver to *provide* DNS information, then its address will either have
to be resolvable in the namespace or hardcoded into other nameservers'
configurations.


- Kevin