O Brother where art thou?

December 7, 2007 12:50 PM

Printer connected via ethernet keeps disappearing from the network. How can I tell if it's a problem with the network, or a problem with the printer?

My lab has a Brother HL-5250DN that we share by connecting it to the network using Ethernet, then printing via TCP. It's a great printer for us -- it's fast, it duplexes, has more than one paper tray -- but in recent weeks it has started flaking out at irregular intervals. It will work fine for a few hours, then at random times it becomes "unavailable", as if it had been turned off. When it is "unavailable" not only do print jobs fail, but the printer does not respond to pings nor its web and telnet interfaces (all of which work fine normally). If I cycle the power, everything works fine for a few hours, but then the printer becomes "unavailable" again until the power is cycled.

One wrinkle to this is that our university is not privately networked, so each jack has a corresponding public IP address (meaning the printer is plugged directly into the Internet). In the past I have had problems with another building resident knocking my computer off the network by mistakenly configuring her computer with my IP address -- whenever she rebooted I lost my network connection. Could the same thing be happening here? Regardless of whether this theory is true or not, how can I tell whether the problem is with the printer itself, or is a problem with the network?

Other information: I have the printer configured to use a static connection, with the proper IP address / subnet mask / gateway / DNS information. When the printer is not responding I can check the printer's configuration by pressing buttons on its control panel, and all of the TCP/IP settings are correct. As I said, right after startup everything works great, so I don't think that it's misconfigured (I could, of course, be wrong -- wouldn't be the first time). Also, my building has an old non-switched network, so my understanding is that from another network node I should be able to monitor the entire subnet's TCP traffic. I am hardly a network ninja, but if I understand this correctly, would tcpdump tell me something useful?

posted by harkin banks to computers & internet (11 comments total)

I have the same problem with a very similar Brother printer (if it's not the same thing, it's a slightly earlier version), running on a very simple home network. Sometimes it will stay up for weeks, sometimes it won't. I think it's just a bug in the printer.
posted by xil at 1:00 PM on December 7, 2007

Try ping -t to see if it ever loses network connectivity.
posted by mphuie at 1:22 PM on December 7, 2007

yep, I'm doing that, and it answers pings for a variable period after the power is cycled (usually about 1 - 4 hours), then stops along with its ability to accept print jobs.
posted by harkin banks at 1:39 PM on December 7, 2007

Have you tried updating the firmware?
posted by Orb2069 at 2:17 PM on December 7, 2007

The printer reports that its firmware has the same number as the most current version (1.11).
posted by harkin banks at 2:30 PM on December 7, 2007

You might want to try it anyway - It's possible the version on the machine is corrupted in some way that makes it keel over dead.
posted by Orb2069 at 2:36 PM on December 7, 2007

Does dropping off your network correlate with power save settings on the printer? Are you using the Brother print driver, and setting up the printer in Windows to use that driver?

I've seen printers with a built-in print server drop off network connections when the power cycle settings have them off for a long time, and they are on an outlet with low voltage, and then someone sends out a print job, calling for the drum heaters to come on, and the motherboard to wake up, creating a short lived power drop. But, long enough to drop off the network.
posted by paulsc at 3:41 PM on December 7, 2007

Orb2069: I updated the driver as you suggested, and the printer lasted 1 hour 7 minutes before crapping out again. If only it were so easy!

paulsc: Everybody that prints to that printer does so using the Brother print driver, installed directly from the CD that came with the printer.

Your theory about waking from sleep is an interesting one -- I've wondered if that was the problem, but I haven't been able to correlate the printer dropping off the network with time since last print job. The reason is that users are located in three different rooms with the printer in a fourth, so I don't necessarily know when somebody prints a document. I just disabled the power saver (I think), so we'll see if that makes a difference.
posted by harkin banks at 4:33 PM on December 7, 2007

For what it's worth: updating the firmware didn't help me either. And the printer disappears even when nobody's been using it, so I doubt a sudden power dropout is causing it to fail.
posted by xil at 5:39 PM on December 7, 2007

Can you swap this printer with another one, and change both their IP addresses? You can see if the problem follows the printer, or if the replacement printer has the same problem here.
posted by jjj606 at 7:04 PM on December 7, 2007

Packet sniffing is the right approach, but tcpdump is a bit hardcore; I'd use Wireshark.
posted by flabdablet at 4:29 AM on December 8, 2007