[baylisa] Re: wtf: hostid gives '0' as a hostid

Sun Feb 17 15:10:03 PST 2008

On Feb 17, 2008, at 2:18 AM, Rick Moen wrote:
> You might be better off using, say, hashes of sshd host keys.  (Some  
> of
> your hosts might not run an sshd.  You could fix that.  Or not.  ;- 
> >  )

Depending on your hardware vendor it may be possible to get a real
unique ID.  Dells have a software accessible serial number.  The
magic incantation is something like:

     dmidecode | grep Serial\ Number | head -n1.

We used this at the last company I worked for.  Other vendors may have
similar systems.

The deployment system we were building went from bare-metal to full
deployment, so the system had to be able to identify a host before it
could supply an appropriate OS.   Things like network addresses and
SSH keys were installed based on this determined identity.

There are advantages to using an infrastructure specific identifier.    
The
switch port that a machine lives on would be a good one.  This way
location determines function, and you can replace a system simply by
unracking the old box, racking the new box, and turning it on.

-jeff