setup hostname from DNS/DHCP dynamically
 

hello

i have a small setup with a few VMs that i use for testing stuff. And i would like to set these up so that i can have them getting their hostnames from the DNS/DHCP setup.

my VMs are either ubuntu or debian - so i would think they would require the same, or very similar, configurations.

but i have no idea what needs doing.

i am finding difficulty to find any valid information as the keywords that i have used for searching are not really helpful. i have tried searching for:
'hostname dynamic dns dhcp'

if somebody could be so kind to provide me with some idea of the configuration, it would be most appreciated.

thanks,

No, most people leave the hostname alone. This box is RoseViolet wherever she goes.
A handy way of hacking this for yourself is to hack init scripts or the dhclient script to change hostname. Why do you need a different hostname?

i have a template of ubuntu and another for debian Virtual Machine.

so when i create/copy a new VM - i have to edit its hostname as the default will not do; TEMPLUBU, TEMPLDEB

I understand that tools such as Puppet would do this - but would be like just over the top for my requirements.

just to be clearer - there is no off-the-shelve solution for this in Linux?

thanks,

If I'm right, the dhcp can give hostnames after a fashion.

The usual info is dns, and IP. You can grok a dhcp license file to see if there's a spot for hostnames. When it comes to hostname, the server can link an ip to a hostname by simply having a dns entry, and then the outside world makes that link. The dhcp server can link an ip to a mac address. But that's all server side. You can change your hostname by a command like

echo "ShyTalk" > /etc/hostname.

but nobody listens to that normally. Nobody interrogates it normally. If someone is listening, perhaps you should explain to us who and why.

so your suggestion would be to have a script that

after booting, collects the IP of host
nslookup - to collect the hostname for that IP, from the DNS
write that hostname into /etc/hostname

then reboot

is that what you are suggesting?

thanks,

I'm not sure what you are trying to do and I'm not suggesting. I was pointing out that the most important thing is what the outside world thinks your hostname is, not what your box thinks it is.

thanks

i am back where i started.

regards,