[c-nsp] Gigabit link between 2960S and 4948 won't come up

[Maarten Carels]

On 13 Jun 2012, at 14:10 , Gert Doering wrote:

> Hi,
> 
> On Wed, Jun 13, 2012 at 01:06:51PM +0200, Maarten Carels wrote:
>> Used the right crossover cable? I've seen them with only 12/36 crossed and 45/78 not connected. You may need the 12/36 crossed 45/78 straight connected variety.
> 
> GigE-on-copper works perfectly fine with no crossing at all.  Depending
> on the transceivers in question, "crossing some pairs and not others"
> might actually confuse their logic that determines cable layout.

Long time ago I connected a small cisco switch (2940 or so) to a chassis based access switch (4500 with gig-E blades).

It insisted on having the right crosscable (12/36 crossed, 45/78 straight) between them...

Usually not crossing works fine, but sometimes... And beware of 100Mb crosscables that cross 12/36 and leave the rest unconnected.

--maarten



-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 495 bytes
Desc: Message signed with OpenPGP using GPGMail
URL: <https://puck.nether.net/pipermail/cisco-nsp/attachments/20120613/506bd036/attachment.sig>