Nokia 7705 SAR - 3.2.13.3 QoS Adaptation for LAG on Access

7705 SAR Interfaces
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Interface Configuration Guide
3HE 11011 AAAC TQZZA Edition: 01
− An eligible member is a link that can potentially become active. This means
it is operationally up, and if the slave-to-partner flag is set, the remote
system did not disable its use (by signaling standby).
• The selection algorithm works in a revertive mode (for details, refer to the IEEE
802.1ax standard). This means that every time the configuration or status of a
subgroup changes, the selection algorithm reruns. If multiple subgroups satisfy
the selection criteria, the subgroup currently active remains active. This behavior
does not apply if the selection-criteria hold-time parameter is set to infinite.
Log events and traps are generated at both the LAG and link level to indicate any
LACP changes. See the TIMETRA-LAG-MIB for details.
3.2.13.3 QoS Adaptation for LAG on Access
QoS on access port LAGs (access ports and hybrid ports in access mode) is handled
differently from QoS on network port LAGs. Based on the configured hashing, traffic
on a SAP can be sent over multiple LAG ports or can use a single port of a LAG.
There are two user-selectable adaptive QoS modes (distribute and link) that allow
the user to determine how the configured QoS rate is distributed to each of the active
LAG port SAP queue schedulers, SAP schedulers (H-QoS), and MSS schedulers.
These modes are:
• adapt-qos distribute
For SAP queue schedulers, SAP schedulers (H-QoS), and SAP egress MSS
schedulers, distribute mode divides the QoS rates (as specified by the SLA)
equally among the active LAG links (ports). For example, if a SAP queue PIR
and CIR are configured on an active/active LAG SAP to be 200 Mb/s and 100
Mb/s respectively, and there are four active LAG ports, the SAP queue on each
LAG port will be configured with a PIR of 50 Mb/s (200/4) and a CIR of 25 Mb/s
(100/4).
For the SAP ingress MSS scheduler, the scheduler rate is configured on an MDA
basis. Distributive adaptive QoS divides the QoS rates (as specified by the SLA)
among the active link MDAs proportionally to the number of active links on each
MDA. For example, if an MSS shaper group with an aggregate rate of 200 Mb/s
and a CIR of 100 Mb/s is assigned to an active/active LAG SAP where the LAG
has two ports on MDA 1 and three ports on MDA 2, the MSS shaper group on
MDA 1 will have an aggregate rate of 80 Mb/s (200 × 2/5 of the SLA) and a CIR
of 40 Mb/s (100 × 2/5 of the SLA). MDA 2 will have an aggregate rate of 120 Mb/s
(200 × 3/5) and a CIR of 60 Mb/s (100 × 3/5).