Service Manual

Table Of Contents
Configure MTU Size on an Interface
In Dell EMC Networking OS, Maximum Transmission Unit (MTU) is defined as the entire Ethernet packet (Ethernet header +
FCS + payload).
The following table lists the range for each transmission media.
Transmission
Media
MTU Range (in bytes)
Ethernet
594-12000 = link MTU
576-9234 = IP MTU
Link Bundle Monitoring
Monitoring linked LAG bundles allows traffic distribution amounts in a link to be monitored for unfair distribution at any given
time. A threshold of 60% is defined as an acceptable amount of traffic 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
Enable link bundle monitoring on port channel interfaces.
link-bundle-monitor enable
DellEMC(conf-if-po-10)#link-bundle-monitor enable
Configure threshold level for link bundle monitoring.
link-bundle-distribution trigger-threshold
DellEMC(conf)#link-bundle-distribution trigger-threshold
View the link bundle monitoring status.
show link-bundle-distribution
Using Ethernet Pause Frames for Flow Control
Ethernet pause frames and threshold settings are supported on the Dell EMC 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 senders transmission for a period of time.
An Ethernet interface starts to send pause frames to a sending device when the transmission rate of ingress traffic 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 flow control, stations implementing the pause operation instruct the MAC to enable reception of frames with destination
address equal to this multicast address.
Interfaces
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