This article contains information about mismatch in the duplex mode on a NetScaler interface.

Mismatch in the Duplex Mode on a NetScaler Interface

The mismatch in the duplex mode on a NetScaler interface can result in performance issues, intermittent connectivity, and loss of communication. The nic_err_duplex_mismatch counter increments when there is a mismatch in the duplex mode.

Incorrect configuration of interface settings on a NetScaler appliance and Switches results in performance related issues. The most common problems are related to speed and duplex mode configuration. Speed mismatch issues can result in loss of connectivity. Issues with auto-negotiation of duplex modes generally do not result in connection establishment issues. If both the appliances support auto-negotiation, it is recommended to enable auto-negotiation mode on the appliances.

Run the following commands from the command line interface of the appliance to check the speed and duplex mode settings:
show interface <id> 

> show interface 1/8
Interface 1/8 (Gig Ethernet 10/100/1000 MBits) #2
flags=0x4000 <ENABLED, DOWN, down, autoneg, 802.1q>
MTU=1514, native vlan=1, MAC=00:d0:68:15:fd:3d, downtime 162h01m03s
Requested: media UTP, speed AUTO, duplex FULL, fctl OFF,
throughput 0
RX: Pkts(0) Bytes(0) Errs(0) Drops(0) Stalls(0)
TX: Pkts(0) Bytes(0) Errs(0) Drops(0) Stalls(0)
NIC: InDisc(0) OutDisc(0) Fctls(0) Stalls(0) Hangs(0) Muted(0)
Bandwidth thresholds are not set.

Run the following commands from the command line interface of the appliance, to change the speed and duplex mode settings:
set interface <id> [<argument> <setting>]

> set interface 1/8 -duplex full
Done

Run the following command to check the duplex mode and speed settings on a Cisco Switch:
show interfaces interface-id

show interfaces fastethernet0/3

Additional Resources 

• Fast Ethernet (10/100-Mb/s) ports support all speed and duplex mode options

• Gigabit Ethernet (10/100 Mb/s) ports support all speed options and all duplex options (auto, half, and full)

• Gigabit Ethernet (1000Mb/s) ports support all speed options, and auto and full duplex options only