DCQCN config with CX6

  1. Is OFED driver required for dcqcn or can it be enabled with Inbox driver as well? What are the commands to set DCQCN with these 2 drivers?
  2. What is the difference between ROCE_CC_PRIO_MASK_P1 & ROCE_CC_PRIO_MASK_P2?
  3. If PFC is enabled on priority 3 , do we’ve to enable dcqcn on the same priority as well? If yes , is it done via “mlxconfig -d /dev/mst/mt4115_pciconf0 -y s ROCE_CC_PRIO_MASK_P1=0x10”?
  4. How do we know what all values can be set for ROCE_CC_PRIO_MASK_P1?
  5. What does 0x10 ROCE_CC_PRIO_MASK_P1 value signify?
  6. How to check if dcqcn is enabled & working? Yesterday I encountered a case where /sys/class/infiniband/mlx5_0/ports/1/hw_counters/rp_cnp_handled = 68859. So this means Fabrico sends lots of CNP to the NIC. But the NIC doesn’t seem to slow down its TX.
  7. Is any other setting required?

Hello Surinderjeet,

Thank you for posting your inquiry on the NVIDIA Networking Community.

Based on the information provided and required, please review the following community articles:

Even though the articles mention the ConnectX-4, it is similar for the ConnectX-6.

As DCQCN configuration is driven from a f/w perspective, you can enable it with INBOX drivers as well. Be aware support for INBOX drivers is provided by the OS Distro vendor.

If you need any further assistance, we recommended to open a NVIDIA Networking support ticket (Valid support contract required), by sending an email to networking-support@nvidia.com

Thank you and regards,

~NVIDIA Networking Technical Support

the site is not access, pls update the link