Service Manual

Transmission
Media
MTU Range (in bytes)
576-9234 = IP MTU
Link Bundle Monitoring
Monitoring linked LAG bundles allows trac distribution amounts in a link to be monitored for unfair distribution at any given time. A
threshold of 60% is dened as an acceptable amount of trac on a member link. Links are monitored in 15-second intervals for three
consecutive instances. Any deviation within that time sends Syslog and an alarm event generates. When the deviation clears,
another Syslog sends and a clear alarm event generates.
The link bundle utilization is calculated as the total bandwidth of all links divided by the total bytes-per-second of all links. If you
enable monitoring, the utilization calculation is performed when the utilization of the link-bundle (not a link within a bundle) exceeds
60%.
To enable and view link bundle monitoring, use the following commands.
• Enable link bundle monitoring.
ecmp-group
• View all LAG link bundles being monitored.
show running-config ecmp-group
Using Ethernet Pause Frames for Flow Control
Ethernet pause frames and threshold settings are supported on the Dell Networking OS.
Ethernet Pause Frames allow for a temporary stop in data transmission. A situation may arise where a sending device may transmit
data faster than a destination device can accept it. The destination sends a PAUSE frame back to the source, stopping the sender’s
transmission for a period of time.
An Ethernet interface starts to send pause frames to a sending device when the transmission rate of ingress trac exceeds the
egress port speed. The interface stops sending pause frames when the ingress rate falls to less than or equal to egress port speed.
The globally assigned 48-bit Multicast address 01-80-C2-00-00-01 is used to send and receive pause frames. To allow full-duplex
ow control, stations implementing the pause operation instruct the MAC to enable reception of frames with destination address
equal to this multicast address.
The PAUSE frame is dened by IEEE 802.3x and uses MAC Control frames to carry the PAUSE commands. Ethernet pause frames
are supported on full duplex only.
If a port is over-subscribed, Ethernet Pause Frame ow control does not ensure no-loss behavior.
Restriction: Ethernet Pause Frame ow control is not supported if PFC is enabled on an interface.
Control how the system responds to and generates 802.3x pause frames on Ethernet interfaces. The default is rx o tx o.
INTERFACE mode. flowcontrol rx [off | on] tx [off | on]
Where:
rx on: Processes the received ow control frames on this port.
rx off: Ignores the received ow control frames on this port.
tx on: Sends control frames from this port to the connected device when a higher rate of trac is received.
tx off: Flow control frames are not sent from this port to the connected device when a higher rate of trac is received.
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Interfaces