Technical Tip: DNS resolution of hostname to IP

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Description

This article describes how to resolve a hostname to the IP address from the FortiGate CLI.

Scope

For all supported Fortios versions from v6.2.x to v7.6.x.

Solution

To perform a hostname resolution from the FortiGate CLI, the following commands can be used:

execute ping

execute traceroute

Both should return the primary IP address for a given domain. It is assumed, that the FortiGate unit has a valid DNS configured.

Here is an example with mylabdomain.com, returning IP address 172.31.1.1

FGT # execute ping mylabdomain.com

PING mylabdomain.com ( 172.31.1.1 ) : 56 data bytes
64 bytes from 172.31.1.1: icmp_seq=0 ttl=245 time=75.4 ms

FGT # execute traceroute mylabdomain.com

traceroute to mylabdomain.com ( 172.31.1.1 ), 32 hops max, 72 byte packets
1 172.31.1.1  0 ms 0 ms 0 ms

If the resolution does not work, refer to:

Technical Note: FortiGate Troubleshooting DNS commands