Geek Help _ Linux Question

[crokett]

So I flashed the new router with DD-WRT, basically a stripped down version of Linux. I followed these instructions to enable USB support and install printing support.

http://sites.google.com/site/wl520gu/

The crux is to install P910ND - a mini printing daemon intended for diskless workstations. It takes a job received over IP and shoves it directly at the printer with no modification. That actually gives me an idea for installing unsupported printers on a full-fledged Linux box. Anyhoo, it defaults to port 9100 to listen. Problem is I can't print from my XP machiens.

Checking the process gives me this, which is correct.

root@DD-WRT:/etc# ps | grep 910
 3894 root       676 S    /jffs/usr/sbin/p9100d -f /dev/usb/lp0 0

Netstat -a gives me nothing at port 9100 but rummaging around I find this in /etc/services:

root@DD-WRT:/etc# cat services | grep 9100
laserjet        9100/tcp        hplj

I assume that is the problem. They both want to use the same port. I don't see an inetd.conf file and services shows up as an executable. So is that a sound theory? I looked at the man page for P910ND and it is unclear how you specify a different port when starting it.

[dbhost]

TCP port 9100 is the port for Hewlett Packard's Jet Direct print server.

When you configure your XP driver, you need to go into the connection settings and change it from USB to JetDirect and give it the IP address. I have several printers hooked up this way. It works fine.

Does your micro distro of Linux use CUPS at all? Getting Windows to use CUPS is actually reasonably easy...

http://www.owlfish.com/thoughts/wini...003-07-20.html

[crokett]

In XP I installed a new printer. I created an IP printer port using the IP address of the router and 9100 as the port. I then loaded the correct driver for the printer. I don't see any options for JetDirect. However I see the option for spooling vs print directly to the printer. Should I be spooling docs or printing directly to the printer?

I think it may be the printer though. I tried telneting to the printer port and it should print whatever I type there but it is not printing anything. I also tried telneting to the router and echoing text directly to /dev/usb/lp0 and it still did nothing. I am going to try a different printer tomorrow and see what happens.

[cgallery]

I think it may be the printer though. I tried telneting to the printer port and it should print whatever I type there but it is not printing anything.

Only if your printer isn't a "GDI printer" or "winprinter."

From wikipedia.org:

A GDI printer or a Winprinter (similar to a Winmodem) is a print processor that uses software to do all the print processing instead of requiring the printer hardware to do it. It works by rendering an image to a bitmap on the host computer and then sending the bitmap to the printer.

This allows low-cost printers to be built by printer manufacturers, because all the page composition is done in software. Usually, such printers do not natively support a page description language such as PostScript or XPS. A Winprinter uses GDI to prepare the output, which is then passed to the printer driver (usually supplied by the manufacturer) for further processing and only afterwards to the printer itself.[4]

In general, usually, the lowest-cost printers are GDI devices. Most manufacturers also produce more flexible models that add PCL compatibility, or PostScript, or both. In most cases it is only the very lowest-cost models in any given manufacturer's range that are GDI-only.

[crokett]

Any idea how to tell? The printer is a Lexmark x2580 and I can't find any info to confirm this is the case.

[sparkeyjames]

Lexmark x2580

There's your problem right there.

I don't think there is support for some lexmark printers in Linux. Lexmark has chosen to be stingy with driver information. All google links I looked at say that the x2580 is not linux compatible. However Linux can serve as a get data and just shove it through print server for some incompatible printers provided the client sender has the correct drivers for it loaded.

Also all in one printers usually have poor functionality under Linux, at least that has been my experience. The best printers for network use as cgallery pointed out are usually Postscript or PCL types.

/etc/services is just a list of port numbers with there suggested associated use. It does not load drivers or anything of that nature. Do a ps -A | grep lp. If lp turns up you will have find out just what it is doing. lp is the linux standard line printer daemon. It is a bear to configure. I prefer cups ie the common unix printing system. One more thing if you go to print a large document through the router you might well wind up bringing the router knee's do to the cpu and memory resource's in the router being eaten by the printing job.

It's been a while for me but as I recall under windows you have to tell it where to find the printer on the network ie tcp address and port number. If this can be accomplished at least you can print to it if nothing else. Forget about using the scanner or fax.



Jim

[cgallery]

Any idea how to tell? The printer is a Lexmark x2580 and I can't find any info to confirm this is the case.

Pretty sure all the processing for that printer is going to happen on the host CPU (so your telnet test won't work).

But the router should still serve as a print server for the device.

Sounds like you did all the obvious steps. When you're at the XP machine and do a test page, what happens? Does XP toss an error message or something? Any noises coming from the printer?

I've never used a router-based print server (lucky enough that all my printers have built-in servers).

But I did some googling and saw this:
http://sites.google.com/site/wl520gu/

It speaks specifically to setting-up USB printing on an Asus router w/ DD-WRT. Anything in that link help?

[crokett]

Nothing happens at the printer. The XP machine says it sent the job but the job stays in the spooler.

I used that link you reference to set things up originally. Chatted a bit with the guy who wrote it and tried a few more things. Right now I am going to assume it is the printer and try a different model tomorrow.

[sparkeyjames]

GDI windows printers drivers create a binary image to send to a GDI printer.
lp and cups do not like to send unfiltered binary data to a printer and will refuse with no error
messages sent back to the originator. There is a way around it with smb (samba) and
cups.

Start at raw printing and read that section. Then go back and start from the top.

http://www.samba.org/samba/docs/man/...html#id2638565

[crokett]

Ok I read through it and I don't think the linux load on the router is capable, unfortunately. Also there isn't a lot of tweaking I can do because the filesystem is pretty much read-only, at least for the important stuff.

thanks for the link though - I might be able to do this on my linux machine. I will think about it.