What is a Hostname?
A hostname is a label or a name assigned to a device
(like a computer, server, or other network-connected device) on a network. This
name is used to identify the device, making it easier to recognise rather than remember
its numeric IP address. Hostnames are generally human-readable, like my computer, server1, or Biometric.
For example:
- A computer
might have the hostname Office-PC01.
- A server might have the hostname Mail-Server or Web-Server.
.webp "Hostname and Understand Its Relationship with IP Addresses?")
Hostnames are particularly useful in local networks and the internet because
they provide an easier way to identify devices compared to IP addresses, which
can be complex and hard to remember.
How to Change the Hostname?
You can change a device’s hostname through the operating system settings.
Here’s how you can do it in both Windows and Linux/macOS:
Changing Hostname in Windows
1. Open System
Properties:
o
Press Windows + R, type sysdm.cpl, and press Enter.
o
This opens the System Properties window.
2. Change Hostname:
o
Under the Computer Name tab, click on Change.
o
In the Computer Name field, type the new hostname you want to
assign.
o
Click OK.
3. Restart:
o
You will be prompted to restart your computer for the changes to take
effect.
Changing Hostname in Linux/macOS
For Linux and macOS systems, hostnames can be changed through the terminal.
Linux:
1. Open Terminal.
2. Change Hostname: Use the
command:
bash
Copy code
sudo hostnamectl set-hostname
new-hostname
3. Update /etc/hosts:
o
Edit the /etc/hosts file to reflect the new hostname, particularly for the 127.0.0.1 entry.
bash
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sudo nano /etc/hosts
o
Update the line where your old hostname is mentioned and replace it with
the new one.
4. Restart the
system or run sudo reboot.
macOS:
1. Open Terminal.
2. Change Hostname:
bash
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sudo scutil --set HostName
new-hostname
3. Check Hostname:
o
After changing the hostname, you can verify the change with:
bash
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hostname
Link Between Hostname and IP
Address
The hostname and IP address are closely linked but serve different
purposes:
1.
Hostname to IP Address Mapping:
o
Domain Name System (DNS) resolves
hostnames to IP addresses. When you enter a hostname in your browser (e.g., www.google.com), the DNS
converts this human-readable hostname into an IP address (e.g., 142.250.190.78) so the
computer can connect to the correct server.
2.
Local Network (Hosts File):
o
On a local network, hostnames are often mapped to IP addresses in the hosts
file or through local DNS servers. For example, when you type Office-PC on a network,
the system refers to the hosts file or DNS server to find the corresponding IP
address for that hostname.
3.
Static vs Dynamic IPs:
o
In systems with static IPs, the hostname is linked to a specific IP address
that doesn't change. In systems with dynamic IPs (using DHCP), the hostname may
map to different IP addresses at different times depending on what IP address
the DHCP server assigns.
4.
Multiple Hostnames and One IP:
o
A single IP address can have multiple hostnames (this is common with web
servers hosting multiple domains on one server). The DNS system allows multiple
domain names to resolve to a single IP address.
5.
One Hostname and Multiple IPs:
o
A single hostname can also map to multiple IP addresses (for example, a
website with multiple servers for load balancing). In this case, the DNS server
might rotate between the available IP addresses.
A hostname provides a human-readable name for devices on a network, making it easier to recognize them compared to numeric IP addresses. Changing a hostname is simple and can be done through system settings or the command line. The relationship between hostname and IP address is facilitated by systems like DNS, which translate hostnames to IPs, ensuring devices can communicate seamlessly on local networks or the internet.
