DNS servers resolve domain names (For example www.alastair.co.uk) to IP address. The FortiGate uses DNS servers to resolve names to IP address.
The settings for this is under Network > DNS
By default using Fortinet’s FortiGuard severs are select.
It is possible to specify using different DNS server, click on Specify and enter in primary / secondary DNS servers
These settings can be changed in cli
config system dns
set primary {ipv4 address} IP address of primary DNS server, default is FortiGuard server 208.81.112.53
set secondary {ipv4 address} IP address of secondary DNS server, default is FortiGuard server 208.81.112.52
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