When the switch is rebooted, you will find the below log message and the port will be in ready state. The configuration for the SF+_CX3m optic module is not correct - please configure port 1:17 for auto-negotiation Off and speed 10000
Summit X670 EXOS 15.3.1 and lower
xos0055074 - In X670v-48x switch, link goes down after reboot if port is configured with auto negotiation off and speed 1G on both peers when using on using mini gbic.
Upgrade the devices to EXOS 220.127.116.11 patch 1-40 or higher.
Pre-Upgrade Workaround - configure the port for auto-negotiation on and then configure for auto-negotiation off.