Re: Can't ping router.

In article <547868124f.Alan.Adams@xxxxxxxxxxxxxxxxxxxxxxxxxxx>, Alan
Adams <alan.adams@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
In message <4f12635360nospam@xxxxxxxxxxxxxxxxxxxxx> David
<nospam@xxxxxxxxxxxxxxxxxxxxx> wrote:

The router's recognising the RPC as a 10Mb connection but that
seems as far as it goes.

Immediately after pinging the router from the RPC, on the RPC issue
the command

arp -a

That will list the IP and hardware addresses of any system it has
started a negotiation with in the last 15 minutes.

----192.168.0.1 Ping Statistics----
1 packets transmitted, 0 packets received, 100% packet loss
*arp -a
router (192.168.0.1) at (incomplete)

If the router shows up, it means that the RPC has asked who owns IP
address 192.168.0.1, and the router has replied with its own hardware
address. This is an essential step in sending a message, such as
ping, to the router. All messages on ethernet are actually sent to
hardware addresses.

The only times I've seen ARP work, when ping doesn't, are when
pinging a system whose security settings forbid a reply to ping,
such as the Windows firewall, or a wireless interface with the wrong
encryption key.

If arp hasn't worked, then the failure is at a very low level-
usually hardware, e.g. cable, port etc.

Looks ominous, then?

At that stage I would be trying a crossed cable directly from the RPC
to a Mac. With that it should be possible to ping the RPC from the
Mac (but not the reverse for the same reason the Macs won't ping
each other - they are set not to respond to pings. You WILL want to
change that setting on each Mac, so you can do this sort of testing.)

It will only work with a crossed cable, which I don't suppose you
have. They are about 7 pounds from PC World, if you want to explore
that route further.

Probably throwing good money after bad, I think.

If that test also fails, I would suspect the RPC ethernet hardware.

Another test - does the router's web interface allow you to ping
other systems from the router? If so, try pinging the RPC from the
router. If it works, then your problem is a security setting in the
router. (You won't be able to ping the Macs from the router -
security settings on Macs again.)

The web interface allows it but I get 100% packet loss.

Looks like my network card is a dud.

Thanks everyone for all the help.

--
New Marmite(TM): Not as thick! Not as dark! Not as te!

David - toro-danyo atcost uku fullstop co fullstop uk
http://www.toro-danyo.uku.co.uk/
.

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