Service Manual

• fpEgrQBuSnapshotTable
• fpIngPgBuSnapshotTable
• fpStatsPerPgTable
• pfcPerPrioTable
fpEgrQBuSnapshot
Table
This table fetches the BST statistics at Egress Port with respect to the buer used. This table displays the
Snapshot of the Buer cells used by Unicast and Multicast Data and Control Queues.
fpIngPgBuSnapsho
tTable
This table fetches the BST statistics at the Ingress Port with respect to the Shared Cells and the Headroom
cells used per Priority Group. The snapshot of the Ingress Shared cells used and the Ingress Headroom cells
used per Priority Group, when PFC is enabled, will be displayed in this table. This table is indexed by stack-
unit index, port number and the priority group number.
fpStatsPerPgTable This table fetches the Allocated Min cells, Shared cells and Headroom cells per Priority Group, the mode in
which the buer cells are allocated - Static or Dynamic and the Used Min Cells, Shared cells and Headroom
cells per Priority Group. The table fetches a value of 0 if the mode of allocation is Static and a value of 1 if
the mode of allocation is Dynamic. This table is indexed by stack-unit number, port number and priority
group number.
pfcPerPrioTable This table fetches the number of PFC frames transmitted (PFC Requests) and the number of PFC frames
received (PFC Indications) per priority on a per port basis. This table is indexed by the stack-unit index, port
number and priority.
DCB Maps and its Attributes
This topic contains the following sections that describe how to congure a DCB map, apply the congured DCB map to a port,
congure PFC without a DCB map, and congure lossless queues.
DCB Map: Conguration Procedure
A DCB map consists of PFC and ETS parameters. By default, PFC is not enabled on any 802.1p priority and ETS allocates equal
bandwidth to each priority. To congure user-dened PFC and ETS settings, you must create a DCB map. The following is an
overview of the steps involved in conguring DCB.
• Enter global conguration mode to create a DCB map or edit PFC and ETS settings.
• Congure the PFC setting (on or o) and the ETS bandwidth percentage allocated to trac in each priority group, or whether
the priority group trac should be handled with strict priority scheduling. You can enable PFC on a maximum of two priority
queues on an interface. Enabling PFC for dot1p priorities makes the corresponding port queue lossless. The sum of all allocated
bandwidth percentages in all groups in the DCB map must be 100%. Strict-priority trac is serviced rst. Afterwards, you can
congure either the peak rates or the committed rates. The bandwidth allocated to other priority groups is made available and
allocated according to the specied percentages. If a priority group does not use its allocated bandwidth, the unused bandwidth
is made available to other priority groups.
• Repeat the above procedure to congure PFC and ETS trac handling for each priority group
• Specify the dot1p priority-to-priority group mapping for each priority. The priority group range is from 0 to 7. All priorities that
map to the same queue must be in the same priority group.
Leave a space between each priority group number. For example: priority-pgid 0 0 0 1 2 4 4 4 in which priority group 0 maps to
dot1p priorities 0, 1, and 2; priority group 1 maps to dot1p priority 3; priority group 2 maps to dot1p priority 4; priority group 4 maps
to dot1p priorities 5, 6, and 7.
Important Points to Remember
• If you remove a dot1p priority-to-priority group mapping from a DCB map (no priority pgid command), the PFC and ETS
parameters revert to their default values on the interfaces on which the DCB map is applied. By default, PFC is not applied on
specic 802.1p priorities; ETS assigns equal bandwidth to each 802.1p priority.
Data Center Bridging (DCB)
213