Auto-Negotiation

Table 1. Auto-Negotiation product support

Feature

Product

Release introduced

Auto-Negotiation

5320 Series

Fabric Engine 8.6

5420 Series

VOSS 8.4

Note:

SFP-DD ports are only available if you disable Advanced Feature Bandwidth Reservation.

5520 Series

VOSS 8.2.5

Only on the following switch models:

5520-24T

5520-24W

5520-48T

5520-48W

5520-12MW-36W

5520-48SE QSFP28/QSFP+ ports, and all fixed fiber ports, at 1 Gbps only

Note:

QSFP28 ports are only available if you disable Advanced Feature Bandwidth Reservation.

5520-VIM-4XE at 1 Gbps only and 5520-VIM-4YE at 25 Gbps only

5720 Series

Fabric Engine 8.7

The Auto-Negotiation feature enables the device to switch between the various operational modes in an ordered fashion and lets you select a specific operational mode. The Auto-Negotiation feature also provides a parallel detection (called autosensing) function to recognize compatible devices, even if they do not support Auto-Negotiation and helps the device sense the link speed only; not the duplex mode.

You can use the show interfaces gigabitEthernet l1-config command to see the Auto-Negotiation operational state on a port. The operational state uses the configuration and transceiver type present in the port. If you enable Auto-Negotiation for the port but the transceiver type does not support Auto-Negotiation, the operational state is disabled (false).

Important

Important

The software requires the same Auto-Negotiation configuration on link partners to avoid incorrect declaration of link status. Mismatched configuration can cause the links to stay down as well as unpredictable behavior. Ensure the Auto-Negotiation configuration between local ports and their remote link partners match before upgrading software releases.