hostname - macOS

Overview

The hostname command in macOS is used to display or set the system’s host name. This name is used to identify the machine on a network. The command is most effective in network administration, script automation, and system maintenance tasks.

Syntax

The basic syntax for using the hostname command is:

hostname [options]

To set the hostname:

sudo hostname <new_hostname>

Where <new_hostname> is the name you wish to assign to your machine.

Options/Flags

hostname supports a few options that control its execution:

-s, --short: Display the short host name (the portion before the first dot) only.
-f, --fqdn, --long: Display the FQDN (Fully Qualified Domain Name), which is the long host name.
-i, --ip-address: Display the IP addresses associated with the host name.
-a, --alias: Display the alias name of the host, if used.
-d, --domain: Display domain name of the host.
-A, --all-fqdns: Display all FQDNs of the machine.
--help: Display help information.
--version: Display version information.

Examples

Display the current host name:
```
hostname
```
Set a new host name:
```
sudo hostname new-host-name
```
Display the IP address of the host:
```
hostname -i
```
Display the short version of the host name:
```
hostname -s
```
Display the fully qualified domain name (FQDN):
```
hostname -f
```

Common Issues

Permission Denied: When setting a new hostname, you need administrative privileges. Ensure you use sudo to avoid this error.
Hostname Not Persisting After Reboot: Changes made using hostname might not persist through a reboot. To permanently change the hostname, use the scutil command:
```
sudo scutil --set HostName <new_hostname>
```

Integration

Combine hostname with other commands to perform more complex tasks. For example, logging the host name and IP in a log file:

echo "$(date) - Host: $(hostname -s) - IP: $(hostname -i)" >> system.log

This can be used in scripts to track the network status of multiple machines.

scutil: Manage system configuration parameters.
ping: Check network connectivity.
ifconfig: Configure or display network interface parameters.

For further reading and more detailed information, you can consult the macOS man pages available via man hostname in your terminal.