Author: Rob Malpass Date: To: Hampshire LUG Discussion List Subject: Re: [Hampshire] NAS devices and MTU
----- Original Message -----
From: "James Courtier-Dutton" <james.dutton@???>
To: "Hampshire LUG Discussion List" <hampshire@???>
Sent: Friday, January 01, 2010 7:59 PM
Subject: Re: [Hampshire] NAS devices and MTU
>MTU is most likely a red herring here.
>Regarding the Auto-negotiation.
>There is an extra variable to consider.
>Modern Ethernet ports contain an auto negotiation of MDX (Crossover
>cable or not)
>If you switch off Auto negotiation of Speed/Duplex, you also switch off
>MDX.
>This would explain the ReadyNAS dying when you switch to manual full
>or half duplex 100Mbps.
>If you are using a CAT5 crossover cable, try replacing it with a
>straight through cable and visa versa.
I couldn't tell whether the supplied cable was crossover but swapped with a
known
straight through cable. Speeds largely the same - up from 860KBps to
880KBps.
>As for things to try:
>1) Try to determine what the auto-negotiation resulted in each end of
>the cable link.
>If they turn out to be different, you most likely have a cable problem.
>You do not make it clear what devices are on the network and how are
>they connected together. Is a network switch involved or not etc.
There are no switches involved and all of the hubs are quite old. The
connection goes
from NAS to hub a then hub a to hub b, then hub b to hub c, then hub c to
router and the
client machine is plugged into the router. I'm unable to move the NAS
device into the
router because of a curiosity with another of my NAS devices (Bufallo
linkstation)
which for some reasons insists on being plugged into the router otherwise it
disappears
off the network.
>2) If you are using straight through CAT5 cables, try replacing them
>with crossover ones. Again, if I knew how the network was arranged I
>could tell you the correct cables to use where.
