FortiGate
FortiGate Next Generation Firewall utilizes purpose-built security processors and threat intelligence security services from FortiGuard labs to deliver top-rated protection and high performance, including encrypted traffic.
nithincs
Staff
Staff
Article Id 191032
Description
From the GUI, configure single DNS server IP is possible.

This articles describes how to add secondary DNS server in dialup IPsec VPN setting from CLI.
Solution
Edit the VPN tunnel from CLI.
# config  vpn ipsec phase1-interface
    edit <vpn name>
        set dns-mode manual
        set ipv4-dns-server1 3.3.3.3
        set ipv4-dns-server2 4.4.4.4
    end
Dialup VPN client will get 3.3.3.3 as primary and 4.4.4.4 as secondary DNS server.

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