Any Network gurus help? (TCP/IP)

[Gadget]

I'm well confused with this one:
Just moved a network printer between sites, changed the IP address so I could see it on this site's network.
Simple.

Except I can't even ping it from another machine on the network.
I can plug my laptop into the same network point and see/be seen on the network without a problem.
I can plug my laptop into the printer via a cross-over cable and ping/print to it.

AAaaaarg!

Anyone any ideas? {please }

[Dreadful Scathe]

wrong subnet ?

[El Salsero Gringo]

First thought: network point configured for wrong speed (100MBit/s only) and printer only capable of 10MBit/s

Also, are you using the same cable to connect your laptop to that port as the non-responding printer? I'm sure you are, but worth asking, just in case.

[Trousers]

if DS's suggestion didn't crack it do you know if you are running Hubs or Switches.
if on switches you may Need to reboot them - i find them notoriously bad at re-establishing or adding new addresses once the've been working for a while.

[Spice 'n' Easy]

Also check whether you have the right default gateway?

[El Salsero Gringo]

Next question: if you have an intelligent switch, query the port status and see whether it is a) up and b) if the MAC address for the printer gets loaded into the switch's forwarding table c) if the MAC address for the printer makes it into the remote host you're pinging from

[Gadget]

cool - thanks for the ideas, unfortunatly I can cross off most of them:

The subnet mask is a simple 255.255.255.0, and if it was wrong, the cross-cable connection shouldn't work (should it?)

The Gateway should only be used to connect to an external network or internet (and is correct anyway) {... hmmm, need to see if I can access it through the gateway - long shot, but... nope.}

The network is running on hubs; 10/100 hubs, so the connection shouldn't matter {... but it gives me something else to look at I hadn't thought on ... actually, you may be onto something...}

It's fixed addresses and I have no idea how to look for the printer's MAC address across the network (I've never had any occasion to even look at it on the printer before)

[El Salsero Gringo]

Originally Posted by Gadget

cool - thanks for the ideas, unfortunatly I can cross off most of them:

The subnet mask is a simple 255.255.255.0, and if it was wrong, the cross-cable connection shouldn't work (should it?)

The Gateway should only be used to connect to an external network or internet (and is correct anyway) {... hmmm, need to see if I can access it through the gateway - long shot, but... nope.}

The network is running on hubs; 10/100 hubs, so the connection shouldn't matter {... but it gives me something else to look at I hadn't thought on ... actually, you may be onto something...}

It's fixed addresses and I have no idea how to look for the printer's MAC address across the network (I've never had any occasion to even look at it on the printer before)

Problems like this are usually down to physical or MAC layer stuff, not IP problems.

Definitely worth checking the port status on the switch with the printer attached - that's usually the problem. See if you can force the port speed on the hub to 10MBit. That fixes a problem where the two ends of the link are failing to negotiate a port speed. That's happened to me in the past.

If the port is definitely "up", then chase out the MAC address forwarding table on the switch. Most likely by that time you'll have the problem fixed. BTW If you're on a windoze system, you can look at your ARP cache with "arp -a" from a cmd window (if you weren't aware.)


Good luck.

[Gadget]

Bugger.

Looks like the hub ain't switching down to 10.... although I've got another printer (from the same maufacturer) on the same network and that works... this is such a pile of poo!

[Gadget]

solved.

Required the use of a 8m long network cable, a 5 port mini-switch, an elastic band and some stickyback plastic, but all seems to be working now. Thanks to all.