On QFX10002, QFX10008, and QFX10016 switches, there are 100-Gigabit Ethernet ports that work either as 100-Gigabit Ethernet or as 40-Gigabit Ethernet, but are recognized as 40-Gigabit Ethernet by default. The 40-Gigabit Ethernet ports can operate independently or be channelized into four 10-Gigabit Ethernet ports as part of a port range. Ports cannot be channelized individually. Only the first and fourth port in each 6XQSFP cage is available to channelize as part of a port range. In a port range, the ports are bundled with the next two consecutive ports. For example, if you want to channelize ports 0 through 2, you would channelize port 0 only. If you try to channelize a port that is not supported, you will receive an error message when you commit the configuration. Auto-channelization is not supported on any ports.
 

When a 40-Gigabit Ethernet transceiver is inserted into a 100-Gigabit Ethernet port, the port recognizes the 40-Gigabit Ethernet port speed. When a 100-Gigabit Ethernet transceiver is inserted into the port and enabled in the CLI, the port recognizes the 100-Gigabit Ethernet speed and disables two adjacent 40-Gigabit Ethernet ports.


1)To reconfigure 100G to 40G:

[edit chassis fpc fpc-slot pic pic-slot]
user@switch# set port port-number channel-speed speed
 

For example, to configure ports 0 through 2 on PIC 0 to operate as 40-Gigabit Ethernet ports:

[edit chassis fpc 0 pic 1]
user@switch# set port 0 channel-speed 40g

2)Review your configuration and issue the commit command.

[edit]
user@switch# commit
commit complete

3) To map this converted 40G to aggregated bundle, configure the speed manually on both local and remote side, below is the sample configuration:

user@switch# set interfaces ae0 aggregated-ether-options link-speed 40g


To return a range of ports on QFX10002-72Q, QFX10008, or QFX10016 switches to the default 40-Gigabit Ethernet configuration, delete the 40g statement:

[edit chassis fpc 0 pic 1]
user@switch# delete port port-number channel-speed speed