Example of Viewing DEI-Marking Configuration
To display the DEI-marking configuration, use the show interface dei-mark [interface slot/
port | linecard number port-set number] in EXEC Privilege mode.
Dell#show interface dei-mark
Default CFI/DEI Marking: 0
Interface Drop precedence CFI/DEI
--------------------------------
Gi 0/1 Green 0
Gi 0/1 Yellow 1
Gi 8/9 Yellow 0
Gi 8/40 Yellow 0
Dynamic Mode CoS for VLAN Stacking
One of the ways to ensure quality of service for customer VLAN-tagged frames is to use the 802.1p
priority bits in the tag to indicate the level of QoS desired.
When an S-Tag is added to incoming customer frames, the 802.1p bits on the S-Tag may be configured
statically for each customer or derived from the C-Tag using Dynamic Mode CoS. Dynamic Mode CoS
maps the C-Tag 802.1p value to a S-Tag 802.1p value.
Figure 114. Statically and Dynamically Assigned dot1p for VLAN Stacking
When configuring Dynamic Mode CoS, you have two options:
Mark the S-Tag dot1p and queue the frame according to the original C-Tag dot1p. In this case, you
must have other dot1p QoS configurations; this option is classic dot1p marking.
Mark the S-Tag dot1p and queue the frame according to the S-Tag dot1p. For example, if frames with
C-Tag dot1p values 0, 6, and 7 are mapped to an S-Tag dot1p value 0, all such frames are sent to the
queue associated with the S-Tag 802.1p value 0. This option requires two different CAM entries, each
in a different Layer 2 ACL FP block.
NOTE: The ability to map incoming C-Tag dot1p to any S-Tag dot1p requires installing up to eight
entries in the Layer 2 QoS and Layer 2 ACL table for each configured customer VLAN. The scalability
of this feature is limited by the impact of the 1:8 expansion in these content addressable memory
(CAM) tables.
Service Provider Bridging 835