[conspire] corrected to HP LaserJet4M Plus Re: HP LaserJet4 - CUPS lists printer twice

Rick Moen rick at linuxmafia.com
Tue Aug 25 13:18:02 PDT 2009

Just to elaborate on one of the other things I wrote:

> Quoting Darlene Wallach (freepalestin at dslextreme.com):
>> I spoke briefly with Daniel on Saturday. He reminded me I don't have
>> a router and therefore no way to get an ip for the printer.
> Eh?  There's no connection between routers and "getting an IP".  It's
> possible that what Daniel is thinking about, however, is DHCP leases.

What casual computer users commonly call a "router" these days is
something like a Netgear or Linksys residential-gateway device, intended
to connect a home or small office to broadband or other uplink
connections, e.g., the famously hackable Linksys WRT54G and successors

As an example of such devices, the WRT54G fulfills several separate

o  It's a four-port ethernet switch, plus fifth port for uplink.
o  It's a wireless gateway (802.11b/g).
o  It offers private IPs on the internal four ports, with NATed
   service routed to a public IP (on a different network) assigned to the 
   single uplink port -- in which sense, it's a router.
o  It offers IP/port filtering on traffic NATed and routed to/from the 
   uplink port (so-called "firewalling").
o  It offers DHCP leases to the four inside ethernet ports and 
   wireless network -- in which sense, it's a DHCP server.

Now, one of the things I keep forgetting is how much computer users,
these days, tend to take DHCP for granted.  People nowadays plug
computers into wired networks (or connect to wireless ones) and just
assume a DHCP daemon somewhere will automagically provide a suitable IP
address, netmask, gateway IP, set of DNS IP addresses, and maybe even
hostname and other useful information -- without the user getting
involved at all.  That's indeed usually the case, and (usually) pretty

My impression, from your posts, is that you have an old-fashioned setup
of one or more computer with static IP assignments (probably RFC1918
private IPs) configured into them, and an ethernet hub.  Thus, no DHCP
daemon anywhere.  (If you had reason to establish one, you could run the
ISC DHCP daemon on your Linux machine -- but I doubt you need it.)

That's actually a perfectly fine and satisfactory arrangement, is
how most people did TCP/IP in most places for a long time, and is
_still_ the obvious way to do things for any host (including a printer)
that's intended to provide network services to other machines.  It
remains my personal preference and habit.

Once configured, a machine's static IP setup _stays_ configured.  It's
simple, reliable, and there's essentially nothing to go wrong.

More information about the conspire mailing list