My servers are currently have 25Gbps NIC, but switch ( Cisco Nexus 9300 series) has only 400Gbps.
I would like to be able to break out the 400Gbps connection into four 25Gbps connections. Is this possible? If not, what are my other options?
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Sign up to join this communityMy servers are currently have 25Gbps NIC, but switch ( Cisco Nexus 9300 series) has only 400Gbps.
I would like to be able to break out the 400Gbps connection into four 25Gbps connections. Is this possible? If not, what are my other options?
Yes
According to this page, each port of the Nexus 9300 is breakout capable.
You can configure the interface with the interface breakout module
command.
Of course you will need the ad-hoc cable.
It is not obvious from this page from Cisco that you can goes from 400G to 25G (only 400 -> 100 is listed), however, in this guide in scenario 7 and 8, the 400G to 25G options are cited:
That's possible.
Assuming an N9K-C9316D-GX, 9364D-GX2A, 9348D-GX2A, or 9332D-GX2B:
Breakout supported on all ports, 1-16: 2x200, 4x100, 2x100, 8x50, 4x50, 2x50, 4x25, 4x10
According to the Breakout Cable Ordering Guide, for instance a QSFP-100G-SR4-S should be able to connect to 25GBASE-SR modules on the server side, using an appropriate optical breakout cable or harness (MPO12↔4x2xLC MMF).
Using a DAC breakout could also be possible but might cause compatibility options with your server NICs. I'd stick to fiber.