FortiGuard troubleshooting


This section contains tips to help you with some common challenges of using FortiGuard.

FortiGuard services appear as expired/unreachable.

Verify that you have registered your FortiGate unit, purchased FortiGuard services and that the services have not expired at

Services are active but still appear as expired/unreachable.

Verify that the FortiGate unit can communicate with the Internet by accessing FortiGate CLI and using the command execute ping You can also use the execute traceroute command to troubleshoot connectivity to the Internet.

The FortiGate is connected to the Internet but can’t communicate with FortiGuard.

If you have not done so already, verify your DNS settings and ensure that an unblocked port is being used for FortiGuard traffic.

If the FortiGate interface connected to the Internet gets its IP address using DHCP, go to System > Network > Interfaces and edit the Internet-facing interface. Ensure that
Override internal DNS is selected.

Communication errors remain.

FortiGate units contact the FortiGuard Network by sending UDP packets with typical source ports of 1027 or 1031, and destination ports of 53 or 8888. The FDN reply packets would then have a destination port of 1027 or 1031. If your ISP blocks UDP packets in this port range, the FortiGate unit cannot receive the FDN reply packets.

To avoid port blocking, you can configure your FortiGate unit to use higher-numbered ports, such as 2048-20000, using the following CLI command:

config system global
set ip-src-port-range 2048-20000

Trial and error may be required to select the best source port range. You can also contact your ISP to determine the best range to use.

Victoria Martin

Victoria Martin

Technical Writer at Fortinet
Victoria Martin works in Ottawa as part of the FortiOS technical documentation team. She graduated with a Bachelor's degree from Mount Allison University, after which she attended Humber College's book publishing program, followed by the more practical technical writing program at Algonquin College. She does need glasses but also likes wearing them, since glasses make you look smarter.
Victoria Martin

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