[Info-vax] hub better than switch?!

[Albrecht Schlosser]

On 07.03.2012 22:06, Phillip Helbig---undress to reply wrote:
> In article<jj78r8$n2t$1 at dont-email.me>, Albrecht Schlosser
> <vms-news at go4more.de>  writes:
>
>> NODE Device Characteristics EWA0 (7-MAR-2012 09:57:41.66):
>>                     Value  Characteristic
>>                     -----  --------------
>> ...look here:
>>                       Yes  Full duplex enable
>>                       Yes  Full duplex operational
>> ...and here:
>>               TwistedPair  Line media type
>>                      1000  Line speed (mbps)
>>                   Enabled  Auto-negotiation
>>                   Enabled  Flow control
>
> JANDER Device Characteristics EWA0 (7-MAR-2012 22:05:10.77):
>                    Value  Characteristic
>                    -----  --------------
>                     1500  Device buffer size
>                   Normal  Controller mode
>                 External  Internal loopback mode
>        08-00-2B-86-62-C2  Default MAC address (Hardware LAN address)
>                           Multicast address list
>                 Ethernet  Communication medium
>        FF-FF-FF-FF-FF-FF  MAC address (Current LAN address)
>                      128  Minimum receive buffers
>                      256  Maximum receive buffers
>                      Yes  Full duplex enable
>                      Yes  Full duplex operational
>        08-00-2B-86-62-C2  MAC address (Current LAN address)
>              TwistedPair  Line media type
>                      100  Line speed (mbps)
>                        0  Failover priority
>                  Link Up  Link state
>                  Enabled  Auto-negotiation

This looks all reasonable, and Auto-negotiation is enabled. The
only significant difference is that in your output I can't see
"Flow control". Looking at an Alpha (OpenVMS V7.3-2) I can't see
it either, so this might be a problem if it is not enabled by
default (or if it doesn't work or is not enabled at the switch).

Looking back at your original post: you wrote that you get the
errors on the machine with the 100Mb/s interface (the others
have 10). So this looks like maybe a flow control/data overrun
problem could be the cause. I don't have any more ideas. If
you could reset the (LANCP) counters and watch the error
counters, then we might see a relation...

Albrecht