Extreme Networks ExtremeWare XOS 11.3, Manual

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Guidelines for Configuring QoS
ExtremeWare XOS 11.3 Concepts Guide
309
Guidelines for Configuring QoS
The following are useful guidelines for configuring QoS:
●
If you are using DiffServ for QoS parameters, Extreme Networks recommends that you also
configure 802.1p or port-based QoS parameters to ensure that high-priority traffic is not dropped
prior to reaching the Master Switch Module (MSM) on modular switches.
●
The command to replace the 802.1p or DiffServ value affects only those traffic groupings based on
explicit packet class of service and physical/logical groupings.
Egress Traffic Rate Limiting—BlackDiamond 8800
Family of Switches and Summit X450 Switch Only
You can configure the maximum egress traffic allowed per port by specifying the committed rate, or
you can allow the egress traffic to pass an unlimited flow.
You can limit egress traffic on a 1 Gbps port in increments of 64 Kbps; on a 10 Gbps port, you can limit
egress traffic in increments of 1 Mbps. Optionally, you can also configure a maximum burst size, which
is higher than the limit, allowed to egress the specified port(s) for a burst, or short duration.
The default behavior is to have no limit on the egress traffic per port.
To view the configured egress port rate-limiting behavior, issue the following command:
show ports {mgmt | <port_list>} information {detail}
You must use the
detail
parameter to display the Egress Port Rate configuration and, if configured, the
Max Burst size. Refer to “Displaying Port Configuration Information” for more information on the
show
ports information
command.
You can also display this information using the following command:
show configuration vlan
The following is sample output from the
show configuration vlan
command for configured egress
rate limiting:
# Module vlan configuration.
#
create virtual-router "VR-Default"
configure virtual-router VR-Default add ports 3:1-48
create vlan "Default"
configure vlan Default tag 1
config port 3:1 rate-limit egress 128 Kbps max-burst-size 200 Kb
config port 3:2 rate-limit egress 128 Kbps
config port 3:10 rate-limit egress 73 Kbps max-burst-size 128 Kb
configure vlan Default add ports 3:1-48 untagged
NOTE
Refer to Chapter 13 for more information on limiting broadcast, multicast, or unknown MAC traffic ingressing the
port.