Re: qfx 5100 48 t 1G interface configuration (ge-x/x/x)vs 10G xe-x/x/x

With 14.1X53-D30 and prior our 48T's happily negotiated 1Gb properly and successfully on xe interfaces. Upon upgrading to D35 negotiation failed completely. The solution was to ensure autonegotiate is configured.

set groups set_autoneg interfaces <xe-*> ether-options auto-negotiation
set apply-groups set_autoneg

Juniper's documentation is confusing and fails to take into account 1Gb behavior on 10Gb interfaces:

"Default
Autonegotiation is automatically enabled for Gigabit Ethernet interfaces. Autonegotation is not an option for 10-Gigabit Ethernet interfaces. No explicit action is taken after the autonegotiation is complete or if the negotiation fails."

http://www.juniper.net/documentation/en_US/junos14.1/topics/reference/configuration-statement/autonegotiation-edit-interfaces-qfx-series.html

Confusingly, Juniper also claims in the same reference: "Note: Autonegotation is not supported on QFX5100 devices."

--Paul