Technical Tip: Unable to set 25 GB speeds for ULL (Ultra Low Latency Slots) interface on NP7 platform

This article describes that ULL (Ultra Low Latency Slots) which are supported for 25GE /SFP28 interface can detect 25GB transceiver, but the interface setting does not show 25Gbps speed as an option.

NP7 Platform, v6.2.x and above.

ULL interface is marked to 10 Gb by default, to enable 25 Gb speed, an NPU level command is required.

For Devices with VDOMS, log in as super_admin and modify the settings user:

config system global

    config system npu

Before:

config system npu

    set ull-port-mode 10G

end

ULL interface:

MID-FG601F-01 (x6) # set speed

10000full    10G full-duplex.

diagnose npu np7 port-list

x1       10000           10000            n/a             0         6

x2       10000           10000            n/a             0         7

x3       10000           10000            n/a             0         4

x4       10000           10000            n/a             0         5

x5       10000           10000            n/a             n/a       n/a        n/a

x6       10000           10000            n/a             n/a       n/a        n/a

x7       10000           10000            n/a             n/a       n/a        n/a

x8       10000           10000            n/a             n/a       n/a        n/a

-------- --------------- ---------------  --------------- --------- ---------- 

After:

config system npu

    set ull-port-mode 25G

end

MID-FG601F-01 (x6) # set speed

25000full    25G full-duplex.

diagnose npu np7 port-list

x1       10000           10000            n/a             0         6

x2       10000           10000            n/a             0         7

x3       10000           10000            n/a             0         4

x4       10000           10000            n/a             0         5

x5       25000          25000            n/a             n/a       n/a        n/a

x6       25000          25000            n/a             n/a       n/a        n/a

x7       25000          25000            n/a             n/a       n/a        n/a

x8       25000          25000            n/a             n/a       n/a        n/a

A reboot will automatically take effect. Choose to change the interface speed.

In case of a cluster, all cluster members will be rebooted simultaneously; therefore, a maintenance window is required.

NP7 ULL port mode speed change will take effect after the system reboot.

Do you want to continue? (y/n)y

Note that when traffic is properly offloaded to the NPs, operating at 25Gbps should have minimal direct impact on main CPU performance. Any high CPU utilization observed under these conditions should be investigated further by opening a TAC case and providing the relevant logs, including, but not limited to, those described in the following guides:

• Troubleshooting Tip: How high CPU usage should be investigated
• Technical Tip: Debugs for troubleshooting high CPU issues

To validate whether an interface is supported or not, look up the datasheet for the product.

In this instance, it is for a FortiGate-601F with ULL interfaces supported. Interfaces are X5 to X9, where one could only set 10Gb speeds, although the interface supports 25Gb.

If there are issues where, after setting 25GE on the interface and the interface is still down, view the related article below and change the FEC settings.

This is only supported on interfaces that support 25GE.

Related articles:
Technical Tip: 25 Gigabit Ethernet connection between FortiGate and Cisco Nexus
Troubleshooting Tip: 25 Gigabit Ethernet connection between FortiGate and Cisco Nexus

Technical Tip: Reboot after changing ULL (Ultra Low Latency Slots) interface on NP7 platform with FortiGates in High Availability (HA)