Users Guide

Packet handling during MTU mismatch
When you congure the MTU size on an interface, ensure that the MTU size of both ingress and egress interfaces
are set to the same value for IPv4 trac to work correctly. If there is an MTU mismatch between the ingress and
egress interface, there may be a high CPU usage. If egress interface MTU size is smaller than the ingress interface,
packets may get fragmented.
The following describes the dierence between Link MTU and IP MTU.
Layer 2
Overhead
Dierence between Link MTU and IP MTU
Ethernet
(untagged)
18 bytes
VLAN Tag Tag 22 bytes
Untagged Packet
with VLAN-Stack
Header
22 bytes
Tagged Packet with
VLAN-Stack
Header
26 bytes
Related Commands
• mtu — set the link MTU for an Ethernet interface.
ip name-server
Enter up to six IPv4 addresses of name servers. The order you enter the addresses determines the order of their use.
Syntax
ip name-server ipv4-address [ipv4-address2...ipv4-address6]
To remove a name server, use the no ip name-server ip-address command.
Parameters
ipv4-address Enter the IPv4 address, in dotted decimal format, of the name server to be used.
ipv4-address2...
ipv4-address6
(OPTIONAL) Enter up ve more IPv4 addresses, in dotted decimal format, of name
servers to be used. Separate the addresses with a space.
Defaults No name servers are congured.
Command Modes CONFIGURATION
Command History
This guide is platform-specic. For command information about other platforms, see the relevant Dell EMC
Networking OS Command Line Reference Guide.
Version Description
9.10(0.1) Introduced on the S6010-ON and S4048T-ON.
9.10(0.0) Introduced on the S3148.
IPv4 Routing 907