Description |
This article describes the steps for troubleshooting CRC errors. |
Scope | FortiGate 5.X, 6.X and 7.X. |
Solution |
CRC errors are mainly Layer-1 issues. Check for physical connectivity issues.
This problem occurs also when one side of a link is configured on auto-duplex and the other fixed (full-duplex).
Duplex mismatches cause very big performance problems, so be very sure both sites of a link are configured the same.
Check if the port speed/duplex settings are the same on both ends. There might be a duplex mismatch and change the speed via the following CLI commands:
conf sys interface edit <interface-name> set speed<1000full/10000half/100full/100half/10full/10half/auto> end
diag netlink interface list name <interface>
To clear the counters:
diag netlink interface clear <interface
Troubleshooting Tip: Network Interface Card NIC commands. Troubleshooting Tip : FortiGate interface error counters.
If still increasing, replace the cable or SFP if used and check again.
config system interface edit xxxx set vdom “root” set mtu-override enable set mtu 9000 (for example) next end
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