Mini Bytes: If you have successfully installed CentOS 7 in your physical machine or as a virtual machine, then you must do some post installation steps. This will ensure you a better security and make sure your operating system was up to date. In this article you can learn some of the steps to follow after installing CentOS 7.
In my previous article, I told about How to Install CentOS 7 and explained about the CentOS 7 features and reason for using CentOS. In this article, you can learn about how to start using the CentOS 7.
After installing CentOS 7, you must do some post installation steps that will make your operating system secure. You can also do some more GUI tweaks that will make your work environment convenient to you. These are the following steps which you must do after installing CentOS 7.
- Configure Time zone
- Configure Network
- Do System Update
- Switch on or Switch off firewall
- Check start up programs
These are the 5 important steps which you need to follow, after installing CentOS 7. In these 5 steps, you can skip the last 3 steps, but the first 2 steps are more important if you have installed CentOS 7 in virtual machine or as a physical machine.
What ever service you configure, the time and date of the system must be accurate, if not then the service will not run correctly or it will not provide better output. Lets discuss about how to configure all the 5 steps after installing CentOS 7. While running all the below command, make sure you have logged in a root user.
Configure Time zone in CentOS 7:
CentOS 7 has two important directories to configure the time zones., they are located in the following location
- /usr/share/zoneinfo/ -> contains the time zone file.
- /etc/localtime -> contains the local time data which depends on the time zone data in /usr/share/zoneinfo
These are the important locations where you can configure the time zone. To get the current time zone of your system, then run the following command in the terminal.
This command will display the date and time with time zone details like
Thu Aug 18 15:19:50 IST 2016
Here IST stands for Indian standard time. To set the time zone, then you need to run the following command by mentioning the time zone. For example the below command will set the time zone for Asia/Kolkata
# timedatectl set-timezone Asia/Kolkata
You can get the time zone list using the below command in CentOS 7.
# timedatectl list-timezones
Configure Network in CentOS 7:
In order to configure the network in your CentOS 7, you need to have a valid 10/100/1000 mbps Network card installed in your physical machine. If you have installed your OS as a VM, then you need to add a virtual network connection from the VM settings.
How to update CentOS 7 with latest updates:
Before bringing your PC to the production, you must do full system update. This ensures that, all the packages are upto date and make you secure. To update your CentOS, you must use a inbuilt installer called YUM package installer. Yum will be installed in your CentOS 7 while installing the operating system.
Yum was the default package installer, that will be used in CentOS. It was also used as a default package installer in all the fedora distributions. You need to add the repositories in Yum to install packages from online. But in CentOS 7 has default yum repositories that will get you packages from online repository servers.
The following command will update your system with the latest packages. Updating your CentOS 7 monthly once will be good, if your server was in production, then you can update it at the maintenance time. If any critical issues are cleared in the recently released packages, then you can install or update the package immediately.
How to switch on or switch off firewall:
You need to run the following command to disable the firewall in CentOS 7.
systemctl stop firewalld systemctl disable firewalld
The above command will stop the firewall and the next command will disable the firewall at the boot time.
How check start up programs:
In order to check the start up programs, you need to run the following command to list the services.
The above command will list the service which are in the disabled and running state.
Here is the cheat sheet to use in alternative with the systemd utility : Cheat sheet for systemd
With the help of the cheat sheet you can run the commands in systemd by comparing with it.