Guest

Preview Tool

Cisco Bug: CSCuj45686 - 4500 QoS bypass limitations from CSCtx48829

Last Modified

Dec 17, 2018

Products (1)

  • Cisco Catalyst 4500 Series Switches

Known Affected Releases

15.0(2)SG3 15.1(2)SG1.0

Description (partial)

Symptom:
4500 Limitation of minimum bandwidth for any class in a policy map is 32Kb when a strict priority class is used. Able to bypass this limitation by configuring the priority class last in the policy map.

Minimum values to meet the requirements for any class:
100Mb= 4%
10Mb = 32%


DOES NOT WORK ON 10Mb LINK:

policy-map EGRESS-QUEUING
class PRIORITY-QUEUE
    priority
class VIDEO-QUEUE
    bandwidth remaining percent 25

DOES WORK ON 10Mb LINK:

policy-map EGRESS-QUEUING_5C_1P
 class VIDEO-QUEUE
    bandwidth remaining percent 25
 class MISSION-CRITICAL-QUEUE
    bandwidth remaining percent 15
 class TRANSACTIONAL-DATA-QUEUE
    bandwidth remaining percent 10
 class CONTROL-MGMT-QUEUE
    bandwidth remaining percent 6
 class BULK-DATA-QUEUE
    bandwidth remaining percent 1
 class PRIORITY-QUEUE
    priority

Conditions:
4500 configured with a policy-map containing a class with strict priority (with no policer)
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.