What is DHCP?

DHCP (Dynamic Host Configuration Protocol) is a client-server network protocol that automatically assigns IP addresses within a set range. The DHCP server assigns IP addresses as they become free or unused by other members of the network. To achieve its goal a DHCP server can assign IP addresses as follows: Manual or static assignment: assigns an IP address to a specific machine. Automatic assignment: assigns an IP address to a client machine the first time it makes the request to the DHCP server and until the client releases it. And the third way to assign an IP address by a DHCP server is dynamic assignment.

So, let’s start.

Configuring DHCP Server on Rocky Linux 8 / AlmaLinux OS 8 / CentOS 8

Before we start we need to make sure that the server is fully up to date. So, connect to it and update it.

sudo dnf update

Set a static IP address on Rocky Linux 8 / AlmaLinux OS 8 / CentOS 8

The DHCP server must have a static IP address. This is important for the host to be able to do the process well. So, this is our first step.

If you need to know How to set a static IP address on Rocky Linux 8 / AlmaLinux OS 8 / CentOS 8 then you can do it through the post we have prepared for you.

After that, you can continue

Configuring the DHCP server

The package that gives us the ability to deploy the server is dhcp-server So we have to install it

sudo dnf install dhcp-server

The package is fairly lightweight so the installation can be done quickly.

Now we have to edit the server configuration file. The file in question is /etc/dhcp/dhcpd.conf but before editing it create a backup

sudo cp /etc/dhcp/dhcpd.conf /etc/dhcpp/dhcpd.confl.bak

Now proceed to edit it with your favorite text editor. I use nano but you can use vi or vim.

sudo nano /etc/dhcp/dhcpd.conf

Now add the following

default-lease-time 900;
max-lease-time 10800;
ddns-update-style none;
authoritative;
subnet 192.168.20.0 netmask 255.255.255.0 {
  range 192.168.20.10 192.168.20.200;
  option routers 192.168.20.1;
  option subnet-mask 255.255.255.0;
  option domain-name-servers 192.168.20.1;

}

Remember that all these values have to be modified. In this case, I will use some example values.

Thanks to the default-lease-time option we will be able to define how long the DHCP server will reserve an address. While the max-lease-time option will define the maximum. In this case, I have set 900 seconds or 15 minutes for default-lease-time and 10800 minutes or 3 hours for max-lease-time.

Now comes the vital part of the subnet configuration.

In this case, the subnet to configure is 192.168.20.0 and the mask is 255.255.255.0. With the range option you define the range of IP addresses to assign. And with the option router option you can define the default gateway. The subnet mask assignment to each host is defined by the option subnet-mask option. Finally, option domain-name-servers defines the DNS servers to assign to each host.

Finally, when you are done editing the file, save your changes and close the editor.

Now enable and start the option domain-name-servers service.

sudo systemctl start dhcpd
sudo systemctl enable dhcpd

You can check the status of the service,

sudo systemctl status dhcpd

In order for the dhcp service to work properly, you need to open UDP port 67 on your firewall.

Now you just need to configure the network on your client computers for this configuration.

Conclusion

A DHCP server is a simple thing to do, however, it is good to have knowledge about your network to do it correctly.

So, enjoy it!

The post How to configure DHCP Server on RockyLinux 8 / AlmaLinux OS 8 / CentOS 8? appeared first on Linux Windows and android Tutorials.

As we all know Rocky Linux is one of the most anticipated distributions of this year. The so-called, with permission of AlmaLinux OS, the replacement for CentOS, is finally approaching us with a fully stable and production-ready version.

Ideally, if you are starting a new project, you will have to download the ISO image and install it from scratch, but if you have a production server, this may not be ideal. So the migration process although easy can always be problematic.

So, let’s get started.

Migrate from CentOS 8 to Rocky Linux 8.4

The process is quite simple thanks to a script that the community has prepared. So it shouldn’t take that long.

First, you have to completely upgrade your system. This step is essential for the success of the process.

sudo dnf upgrade

Then, reboot the system to make sure all changes are applied including kernel-related changes.

sudo reboot

After the system reboots, we can now download the script.

curl -O https://raw.githubusercontent.com/rocky-linux/rocky-tools/main/migrate2rocky/migrate2rocky.sh
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 27069  100 27069    0     0   128k      0 --:--:-- --:--:-- --:--:--  128k

Now give the script permissions to run

chmod +x migrate2rocky.sh

Now, we can run it locally with the command

sudo bash migrate2rocky.sh -r

This will start the whole migration process which may take some time depending on your computer resources and connection speed.

At the end, you will see a message like the following

And finish the process by rebooting the system

sudo systemctl reboot

When it starts, you can verify the migration by running

cat /etc/os-release

So, enjoy it.

The post How to migrate from CentOS 8 to Rocky Linux 8.4 appeared first on Linux Windows and android Tutorials.

Rocky Linux is a community enterprise Operating System designed to be 100% bug-for-bug compatible with Enterprise Linux, now that CentOS has shifted direction.

This resulted in the creation of a fork to continue the CentOS spirit, this distribution is called Rocky Linux.

Being one of the most awaited distributions because of the importance of CentOS 8, we are getting closer and closer to a stable version. Rocky Linux 8.3 RC1 has been released to speed up the development process.

Although RCs are near-stable releases, the Rocky Linux website tells us that “Under no circumstance should you use a release candidate in a production environment. A release candidate is provided for testing and validation purposes only“. So only use it on a personal computer or virtual machine.

This release is the result of several months of hard work in the process of integrating CentOS into this new distribution. For now, we only have images for the x86_64 and aarch64 architectures.

The exact date when we will have the first stable version? we don’t know yet, but the development team says it will be this year if everything goes well.

Download Rocky Linux 8.3 RC 1

As mentioned above, there are only images for x86_64 and aarch64 architectures. So, you can download them from the corresponding section of the website.

The x86_64 image can be downloaded from this link while the ARM64 (aarch64) image can be downloaded from this link.

Enjoy it!

The post Rocky Linux 8.3 RC1 available appeared first on Linux Windows and android Tutorials.