email@example.com graced my mailbox with this long sought knowledge:
> I've been virtual hosting a bunch of machines and I want to add some
> special functionalities that, at this point, don't seem to be
> possible, at least not with my current level of knowledge.
> My biggest desire is to be able to have a single physical machine that
> has two virtual domains domain1.com and domain2.com each of which has
> a user with a shell account whos username is john (but each with
> different uids).
> that way mail could be sent to either firstname.lastname@example.org and
> email@example.com and Mr. John One could log into domain1.com and see
> his files and mail while Mr. John Two could log into domain2.com and
> see his mail and files but neither could interfere with the other.
> Also if you telnetted to domain1.com, getty would print...
> Trying xx.xxx.xxx.xxx...
> Connected to domain1.com
> Escape character is '^]'.
> domain1.com login:
> instead of the real physical machines domain.
> I don't know enough yet about kernel level stuff dealing with this but
> I would think that maybe there is some way to do this with little or
> no modifications to the kernel.
> for instance NCSA's httpd and wuftpd can distinguish which domain is
> using them and I guess this is done by information received from the
> port connection. I would think that any process (such as getty) or
> the children processes could trace themselves back to the
> port/connection that they are originating from and determine what
> their hostname should be.
> thus is it possible (in some way or another) to configure linux so
> that if you log in to a virtual domain and do a 'hostname' you would
> get the virtual hostname or if you did it a 'who am i' it would also
> give you the virtual hostname?
> Could we keep with each process's info (where/what ever that is) the
> IP address of the "machine" it is running on?
> basically, in all, I would like to further segment a physical machine
> into virtual machines with finer granularity than is now possible.
> Can this be done or is there something fundamental that prevents this?
> Please keep comments regarding sendmail aliasing as a solution to
> yourselves as I already know and implement this and it is not enough.
> especially when you get two clients whos name is bertrum and they both
> want their login name to be bertrum on their "machine". Don't laugh...
> it's not a hypothetical example for me. ugh :-)
> - Jeff Wiegley