F5/Cisco catalyst configuration question

Wed Aug 19 17:41:11 UTC 2009

Scott,

We've had issues in the past with IOS 6500's auto-negotiating uplink ports with an LTM into ISL Trunk mode. This only occurred when we had the port on the LTM configured as a tagged interface. It was easily solved by forcing the port on the 6500 into dot1q encapsulation. I'm not sure this necessarily explains why you aren't seeing a link light on the LTM though. I can't remember what the interface status was on both sides. This does correlate to why it's working on the 2950's as they don't support ISL and would likely negotiate into dot1q.

Chris

Christopher Greves  |  Senior Systems Engineer
One North Lexington Ave, 9th Floor - White Plains, NY 10601
T 914-826-2067  |  C 914.420.8340  |  E christopher.greves at mindspark.com

Mindspark Interactive Network, Inc. is an IAC company.

-----Original Message-----
From: Scott Spencer [mailto:scott at dwc-computer.com] 
Sent: Wednesday, August 19, 2009 1:13 PM
To: nanog at nanog.org
Subject: F5/Cisco catalyst configuration question

Trying to link an F5 Local Traffic Manager with a Cisco Catalyst 6500 , have
matched ports (speed,duplex ect..) but no link light at all on the F5. Does
link with a Cisco 2950 switch in between but I need a direct connection with
the 6500.

Any suggestions what to try?

Best regards,

Scott Spencer
Data Center Asset Recovery/Remarketing Manager
Duane Whitlow & Co. Inc.
Nationwide Toll Free: 800.977.7473.  Direct: 972.865.1395  Fax: 972.931.3340
 <mailto:scott at dwc-computer.com> scott at dwc-computer.com
<http://www.dwc-it.com/> www.dwc-it.com 
Cisco/Juniper/F5/Foundry/Brocade/Sun/IBM/Dell/Liebert and more ~   