Administrator Guide

• All members of a VLAN must have the same IP MTU value.
• Members can have dierent Link MTU values. Tagged members must have a link MTU 4–bytes higher than untagged members
to account for the packet tag.
• The VLAN link MTU and IP MTU must be less than or equal to the link MTU and IP MTU values congured on the VLAN
members.
For example, the VLAN contains tagged members with Link MTU of 1522 and IP MTU of 1500 and untagged members with Link
MTU of 1518 and IP MTU of 1500. The VLAN’s Link MTU cannot be higher than 1518 bytes and its IP MTU cannot be higher than
1500 bytes.
Port-Pipes
A high-speed data bus connection used to switch trac between front-end ports is known as the port pipe. A port pipe is a Dell
Networking-specic term for the hardware path that packets follow through a system.
The MXL switch supports single port pipe only.
Auto-Negotiation on Ethernet Interfaces
By default, auto-negotiation of speed and duplex mode is enabled on 100/1000/10000 Base-T Ethernet interfaces. Only 10GE
interfaces do not support auto-negotiation.
When using 10GE interfaces, verify that the settings on the connecting devices are set to no auto-negotiation.
The local interface and the directly connected remote interface must have the same setting, and auto-negotiation is the easiest way
to accomplish that, as long as the remote interface is capable of auto-negotiation.
NOTE: As a best practice, Dell Networking recommends keeping auto-negotiation enabled. Only disable auto-negotiation
on switch ports that attach to devices not capable of supporting negotiation or where connectivity issues arise from
interoperability issues.
For 100/1000/10000 Ethernet interfaces, the negotiation auto command is tied to the speed command. Auto-negotiation is
always enabled when the
speed command is set to 1000 in IOS.
Setting the Speed and Duplex Mode of Ethernet Interfaces
To discover whether the remote and local interface requires manual speed synchronization, and to manually synchronize them if
necessary, use the following command sequence.
1. Determine the local interface status. Refer to the following example.
EXEC Privilege mode
show interfaces [interface] status
2. Determine the remote interface status.
EXEC mode or EXEC Privilege mode
[Use the command on the remote system that is equivalent to the rst command.]
3. Access CONFIGURATION mode.
EXEC Privilege mode
config
4. Access the port.
CONFIGURATION mode
interface interface slot/port
5. Set the local port speed.
INTERFACE mode
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Interfaces