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Merging SFP+ Ports to QSFP 40G Ports
To remove FANOUT mode in 40G QSFP Ports, use the following commands.
1. Merge 4-10G ports to a single 40G port.
CONFIGURATION mode
no stack-unit port number portmode quad
● stack-unit: Enter the stack member unit identifier of the stack member to reset. The range is from 0 to 5.
● port <port number>: Enter the port number of the 40GbE QSFP+ port. Valid values on base module: 33 or 37;
OPTM SLOT 0: 41 or 45; OPTM SLOT 1: 49 or 53.
● portmode quad: Identifies the uplink port as a split 10GbE SFP+ port.
2. Save the configuration and reload the switch.
CONFIGURATION mode
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● You cannot use split ports as stack-link to stack a switch.
● Split ports cannot be a part of any stacked system.
● The quad port must be in a default configuration before it can be split into 4x10G ports.
● The 40G port is lost in the configuration when the port is split; be sure the port is also removed from other L2/L3 feature
configurations.
● The system must be reloaded after issuing the CLI for the change to take effect.
Configure the MTU Size on an Interface
The link MTU is the frame size of a packet. The IP MTU size is used for IP fragmentation.
If the system determines that the IP packet must be fragmented as it leaves the interface, the system divides the packet into
fragments no bigger than the size set in the ip mtu command.
In the Dell Networking OS, MTU is defined as the entire Ethernet packet (Ethernet header + FCS + payload).
Because different networking vendors define MTU differently, check their documentation when planning MTU sizes across a
network.
The following table lists the various Layer 2 overheads found in the Dell Networking OS and the number of bytes.
Table 27. Layer 2 Overhead
Transmission Media MTU Range (in bytes)
Ethernet
594-12000 = link MTU
576-11982 = IP MTU
Configuring wavelength for 10–Gigabit SFP+ optics
You can set the wavelength for tunable 10–Gigabit SFP+ optics using the wavelength command. To set the wavelength,
follow these steps:
● Enter the interface mode and set the wavelength.
INTERFACE mode
wavelength 1529.0
The wavelength range is from 1528.3 nm to 1568.77nm.
● Verify configuration changes.
Interfaces
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