My Oracle Support Banner

Oracle Linux: Link Speed of Ethernet Interface is Changed from 1Gbps to 100Mbps with out configuration changes (Doc ID 2169185.1)

Last updated on JUNE 24, 2020

Applies to:

Linux OS - Version Oracle Linux 5.0 and later
Oracle Cloud Infrastructure - Version N/A and later
Information in this document applies to any platform.


A NIC, which was linked up as 1Gbps with auto-negotiation at the OS boot time, is suddenly changed to be 100Mbps without any operations. This would happen not only with link speed but also with others like duplex etc.

For example, /var/log/messages shows:

May 15 10:30:39 <host> kernel: ixgbe 0000:40:00.0: eth0: NIC Link is Up 1 Gbps, Flow Control: RX/TX
May 15 10:50:23 <host> kernel: ixgbe 0000:40:00.0: eth0: NIC Link is Down
May 15 10:50:44 <host> kernel: ixgbe 0000:40:00.0: eth0: NIC Link is Up 100 Mbps, Flow Control: RX/TX


To view full details, sign in with your My Oracle Support account.

Don't have a My Oracle Support account? Click to get started!

In this Document

My Oracle Support provides customers with access to over a million knowledge articles and a vibrant support community of peers and Oracle experts.