Things You Should Know the First Time You Power On Your Machine
line speed of auto-negotiation supported devices on the other end of an
ethernet wire.
Important: Auto-negotiate mode is NOT RECOMMENDED if you know the
speed of your ethernet because of possible considerable delay
when booting or when restarting the operating system. This is
because the operating system will start/stop device drivers three
times before the operating system is on-line when booting or
before the operating system relinquishes control to the console on
a shutdown..
Use auto-negotiation ONLY if the DE500-*A is connected to
an ethernet which supports auto-negotiation. Otherwise the
DE500-*A will respond with the default setting of 100Base TX
full-duplex.
3.9.1
Set EW*0_Mode Auto-Negotiate
Example to set the DE500-AA or DE500-BA into auto-negotiation mode:
P00>>> set ewa0_mode auto-negotiate
The DE500-*A then advertises its abilities on the ethernet wire by sending
a link code word on the ethernet wire. If the DE500-*A does not get
a response (a link code word from another auto-negotiation supported
device) the DE500-*A will set its line speed to 100BaseTx full-duplex. It
will take several seconds before you see the SRM console P00>>> prompt
to get the DE500-*A into auto-negotiate mode.
Below is an example of setting the adapter mode to auto-negotiate on a
system where the Ethernet does not support auto-negotiation or there is
no response from the Ethernet. From the console, you see the following
display:
P00>>> set ewc0_mode auto-negotiate
(Note:this takes several seconds)
ewc0: link failed : Using 100BaseTX full duplex
In the above case change ewc0_mode to Twisted to use the DE500-*A in a
10BaseTx environment.
3.9.2
Behavior Note on Systems with Multiple DE500’s
Auto-negotiation mode is NOT RECOMMENDED on DIGITAL UNIX
or OpenVMS systems with more than one DE500 because of possible
considerable delay when booting or when restarting the operating system.
This is because the operating system will start/stop drivers several times
during a boot or reboot. It is recommended that you set the DE500-*A to
the line speed of the ethernet wire instead of using auto-negotiate mode.
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