After just installing a Linux system (such as Ubuntu or CentOS), are you eager to install your business applications? Hold on! Today, I want to emphasize that the first step after installing Linux must be a system update.
1. First, understand: What does a Linux system update actually do?
Many beginners think, “The system just installed is new, what else is there to update?” In fact, the “new” in Linux is different from what we might expect:
The system image (for example, the Ubuntu 22.04 ISO you downloaded) may have been created months ago, during which the Linux community has fixed vulnerabilities, updated drivers, and optimized software—these “new things” will not automatically appear in your freshly installed system; they must be manually synchronized through a “system update.”
In simple terms, updating is like applying patches, fixing vulnerabilities, and enhancing features to transform your “factory version” into the “latest stable version.”
2. A must-read for beginners: Update commands for different distributions (just copy and use)
The update commands for different Linux distributions vary, so don’t mix them up! Here are the three most commonly used commands that you can directly copy into the terminal (make sure you are connected to the internet before executing):
1. Ubuntu/Debian series (most commonly used, such as Ubuntu 20.04/22.04)
Open the terminal (shortcut Ctrl+Alt+T) and enter the following two commands:
First step: Update the software source list
sudo apt updateSecond step: Actually update the system and software (press Y to confirm when prompted)
sudo apt upgrade -y⚠️ Note: After entering sudo, you will be prompted to enter the system password. The screen will not display anything while you type (it’s not unresponsive!), just press Enter after typing.
2. CentOS/RHEL series (such as CentOS 8)
Enter in the terminal:
sudo dnf update -y(Older versions of CentOS use sudo yum update -y, which has the same effect)
3. Fedora series
sudo dnf upgrade -yThe update process may take a few minutes (depending on your internet speed). After it finishes, it is recommended to restart the system to apply the updates.
3. Key issue: Why must the first step be an update?
1. Not updating = exposing “vulnerabilities”
The freshly installed system may come with known vulnerabilities—such as the “Shellshock” vulnerability from last year (which allows hackers to remotely control the computer) and the “Dirty COW” privilege escalation vulnerability (which allows regular users to modify system files).
These vulnerabilities have long been fixed by the Linux community, but the old system in the image still carries them! If you don’t update, your computer is like an unlocked door, easily accessible even to novice hackers.
2. Not updating will likely cause errors when installing software later
For example, if you want to install the Chrome browser or VS Code, Linux will prompt “dependency package version is insufficient” or “compatible components not found”—because the software dependencies in the old system are outdated and incompatible with the new software.
First, update the system to bring all dependency packages up to date, so that subsequent software installations can proceed smoothly without getting stuck on “dependency errors.”
3. Not updating may cause hardware to “misbehave”
Many people find that after installing Linux, their wireless network card doesn’t work, the graphics card driver is not recognized, or the external monitor is unresponsive—this is likely because the hardware drivers in the system are too old!
Linux hardware drivers are updated in sync with system updates, such as patches for NVIDIA graphics cards and Intel wireless network cards, which will only take effect after updating, resolving the “hardware not working” issue.
4. Pitfall reminders: Avoid these misconceptions!
❌ Misconception 1: “Updating will crash the system”
Updates for legitimate distributions (such as Ubuntu LTS and CentOS) are thoroughly tested; as long as you don’t lose internet connection midway or force a shutdown, there is a 99% chance it won’t crash. In fact, not updating is more likely to cause problems.
❌ Misconception 2: “Installing software before updating is fine”
It’s not the same! For example, if you install an old version of Chrome first and then update the system, Chrome may conflict with the new system components; if you update the system first and then install software, you will be installing the version compatible with the latest system.
If your Linux system is already installed and runningbusiness software(such as server-side databases, ERP systems, industry-specific applications, etc.), do not directly apply the “one-click update” from above! At this point, system updates need to be done with extra caution, as blind operations may lead to software crashes, data loss, or business interruptions.