Subject: Re: 'verify' is not diagnostic (thread: lpr desktop printers)
From: R Shapiro (reshapiro@mediaone.net)
Date: Tue Oct 31 2000 - 16:50:10 MST
Ewen Bell writes:
> To answer your question though, I do run an lpr printer under
> MOL/macos and send jobs to an lpd on a linux box elsewhere on my
> network.
Right, I understand that this config works. I was asking about a
different config:
> Are you running the lpd+epson on the SAME linux box that is running
> MOL?
Exactly.
> i'm not familiar with the ethertap stuff, but if the packets
> are being masqeraded then lpd will be expeecting that the requests
> are coming from the masqeraded ip address, not the original.
Masqerading is only for the outside world. As far as the little
single-machine/dual-address intranet is concerned, the macos address
is 192.168.1.2. That's the address the lpd server sees, and that's
the address I put in /etc/hosts.lpd. It's also the file-sharing name
of the mac.
Here's a tcpdump trace of the session:
07:28:36.745046 < 192.168.1.2.721 > [linux_addr].printer: S 2618147389:2618147389(0) win 32768 <mss 1460,wscale 0,nop> (DF)
07:28:36.745046 > [linux_addr].printer > 192.168.1.2.721: S 1433166786:1433166786(0) ack 2618147390 win 32120 <mss 1460,nop,wscale 0 > (DF)
07:28:36.745046 < 192.168.1.2.721 > [linux_addr].printer: P 1:15(14) ack 1 win 32768 (DF)
07:28:36.745046 > [linux_addr].printer > 192.168.1.2.721: . 1:1(0) ack 15 win 32120 (DF)
07:28:36.745046 > [linux_addr].printer > 192.168.1.2.721: P 1:2(1) ack 15 win 32120 (DF)
07:28:36.755050 < 192.168.1.2.721 > [linux_addr].printer: P 15:29(14) ack 2 win 32768 (DF)
07:28:36.755050 > [linux_addr].printer > 192.168.1.2.721: P 2:3(1) ack 29 win 32120 (DF)
07:28:36.755050 > [linux_addr].printer > 192.168.1.2.721: F 3:3(0) ack 29 win 32120 (DF)
07:28:36.755050 < 192.168.1.2.721 > [linux_addr].printer: . 29:29(0) ack 4 win 32768 (DF)
07:28:36.755050 < 192.168.1.2.721 > [linux_addr].printer: F 29:29(0) ack 4 win 0 (DF)
07:28:36.755050 > [linux_addr].printer > 192.168.1.2.721: . 4:4(0) ack 30 win 32120 (DF)
I substituted "[linux_addr]" for the actual linux box address.
This is a perfectly normal tcp session. The only problem is that lpd
thinks the lpr protocol as sent by macos is "screwed up".
IP is basically fine between macos and linux on the same host. I can
run netscape in macos and connect to the http server running in linux
on the same box. I can even run an X server in macos (exodus) and
display X client from linux (which is not quite as ridiculous as it
sounds - it's actually an ok way to get cut-and-paste between the two
environments). Only lpr fails, and only the linux lpd server dumps an
error in /var/log/messages complaining about the protocol.
> Can you send me some info on the filters you have
> for the Epson printer by the way, sounds like an ideal setup!
It's just the usual ones mentioned on
http://216.22.163.20/Linux_Pages/epson740.shtml
I didn't do anything beyond that. You can download them from
ftp://216.22.163.20/epson740.tar.gz.
-- reshapiro@mediaone.net
This archive was generated by hypermail 2a24 : Tue Oct 31 2000 - 17:58:14 MST