Your system needs to have a fully qualified domain name (fqdn) ...
 

Trying to install something in my VM (Ubuntu), I don't even remember now, I got this meddage:

Your system needs to have a fully qualified domain name (fqdn) in order to install the var-qmail packages.
Installation aborted.

Does it mean that I need to get a static IP address for this system?

Now, I do have ThunderBird in the VM and it is working well. What is this error message about?

I also took a screen snapshot and tried to attach it to this post. Hopefully it got there, although I am not sure.

Thanks, - AlexBB

OK, now I found this http://www.leafnode.org/doc_en/README-FQDN.html, read the content but the whole idea is still unclear in many details. It looks I need a static IP address. Why?

for a vm
try something like
" MyVmInstall "
or
" TheOtherOS "

i use on a lan
oldbox1
oldbox2
oldbox3

JohnW, what does it all mean? Ubuntu says MyVmInstall command is not found, likewise the other command is not found also. It seems I get a lot of such "answers." Are you all in the other Universe or what?

I asked specific questions and got what seems to be lunatic answers.

The fqdn would be like www.linuxquestions.org, but since you're talking a local network, you have a few more liberties.

file: /etc/hostname
belch

file: /etc/hosts
192.168.1.117 belch.after.meal
127.0.0.1 localhost lo

The last two parts of the fqdn are relatively insignificant for a local desktop machine. But some apps require you to have it defined and setup. Kind of odd when it's an audio app, but it happens. The IP should match whatever your default route NIC IP is, but I doubt it breaks anything that doesn't actually use the network if it doesn't.

$ man hosts
$ man hostname

Basically it's a network thing where ftp.*.* and www.*.* are on the same network, but are on different machines. I'm by no means an expert, but that seems to be the route that one takes to keep apps that require that stuff happy even though you may not be using anything network related.

Shadow 7, thanks. I will try to comprehend it all. -AlexBB

I think you'll find this https://en.wikipedia.org/wiki/Fqdn explains an FQDN better.

Its basically the 'address-by-name' of your computer on its network (even if you've only got one PC and a router, that's still a LAN).

Also, a computer talks to itself using a reserved network address
(In actual fact this special one is done internally inside the kernel, thus requiring no physical network card or cable, but it still uses the network paradigm).