Linux system administrator: Don't be afraid to upgrade the kernel

One of the most important tasks for Linux system administrators is to be responsible for system kernel upgrades. It is very important for the stability of Linux system to do well to upgrade the kernel of the system. But few dared to escalate the kernel of a Linux system, fearing that it would affect application services on existing Linux systems. However, the risk of kernel upgrades can be greatly reduced as long as the preparation is ready.

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Some people may find Windows operating system upgrade faster, in fact, the Linux system kernel upgrade than the Windows operating system is much faster. Typically, a new version of the kernel comes out every one months. This is why the Linux system is able to cope with the latest attacks.

One of the most important tasks for this Linux system administrator is to be responsible for system kernel upgrades. Upgrading the kernel of the system can fix the vulnerabilities of older versions of the kernel, and can also support more interface devices. It also helps to improve the compatibility of the application, increase the stability of the system and so on. If a new version of the Oracle database system is present, it is better to upgrade the kernel of the Linux system if the database administrator needs to upgrade Oracle. Because there might be some improvements in the latest kernel that could improve compatibility between Linux operating systems and Oracle database systems. Therefore, it is very important for the stability of Linux system to do well to upgrade the kernel of the system. But few dared to escalate the kernel of a Linux system, fearing that it would affect application services on existing Linux systems. It is true that kernel upgrades are a dangerous task. But the system administrator does not need to be bitten by a snake, ten years afraid of twice shy. As long as the relevant preparation before the system kernel upgrade, the system kernel upgrade will not be much of a risk. Specifically, the system administrator needs to be clear about the following several preparation work.

First, need to confirm the purpose of kernel upgrade

There are many goals that can be achieved through kernel upgrades. such as improve the compatibility of the latest equipment, repair the existing system kernel vulnerabilities, improve the stability of the system and so on. To do this before the kernel upgrade, you must first understand the purpose of your system kernel upgrade. Only then will the system administrator be able to determine if there is any need to upgrade. Just like an operation, any surgery can be risky. As the news reported a few days ago, a fracture patient who uses plate fixation can also cause death. The surgery is a small operation in the eyes of most orthopedic surgeons. But it still has a certain degree of risk. For this reason, the concept of risk is still needed when the system kernel is upgraded. Typically, a system administrator needs to determine whether a kernel upgrade is required based on the actual situation of the enterprise. In general, it can be done through other channels, so do not upgrade the system kernel. The system kernel upgrade is done only when other ways are not able to solve the enterprise problem effectively.

For the installation of Oracle database applications, Oracle 0G is required for kernel versions of operating systems such as Linux. If a system administrator needs to deploy an Oracle database system on a Linux operating system, its kernel must be above a certain version. At this point the requirements for the kernel version of the system are a mandatory limitation. For this reason, the system administrator needs to upgrade the Linux operating system kernel. As for the need for some software packages during the transfer process, this does not need to be achieved through kernel upgrades. Instead, you can install related packages directly to address these issues.

Therefore, the system administrator needs to clarify the purpose of the kernel upgrade before the kernel upgrade. Then consider whether this purpose must be achieved through kernel upgrades. If there are other ways, you can try it by other means first. The kernel upgrade is only possible if other methods cannot be implemented. Note that kernel upgrades are risky. Even the experts of the Linux system cannot guarantee that the original application will not have problems after the kernel upgrade. To this end of the process of dealing with kernel upgrades, the system administrator still needs to be cautious.

Second, the upgrade through patching files need to use caution

There are many ways to upgrade a Linux system kernel. Patching a file to fix it is one of them. When the system administrator downloads the kernel upgrade package from the network, it contains the patch files for the kernel. When you upgrade a kernel by patching a file, be aware that it needs to be updated on a per-version basis and not be able to jump. What does that mean? Windows systems now have 98, 000, XP, and so on. This is not able to jump update meaning, is not able to update from 98 directly to XP (the author here is just a metaphor).

When the latest red Hat 9 comes out, the kernel version of the system is: 0. If the system administrator wants to upgrade the kernel by patching the files, from the. 0 upgrade to ... What should the system administrator do now? Typically, a system administrator needs to download one time: To.. A total of five system kernel versions. The corresponding system kernel patch files are included in each system kernel version. The system administrator needs to use the county. The patch file puts the system kernel from the. 0 upgrade to ... And so on and cannot be used directly. Version of the kernel patch file to the system kernel from the. 0 Direct upgrade to ... This is not allowed. This means that by patching files to upgrade the system kernel, it must be done incrementally, and the version must be continuous and not be able to jump.

For this reason, the system administrator must review the current version of the operating system kernel before upgrading the kernel, and then download the subsequent versions accordingly, and not be able to download only the latest kernel version. Then upgrade from low to high. As you can see, patching a file upgrade is like a custom installation in the process of installing an application, providing more flexibility for the system administrator. However, typically only experts on the application recommend this approach. If the system administrator is not very proficient in the Linux operating system or the first time the kernel upgrade of the system, it is best to adopt other simpler kernel upgrade methods, such as reinstalling the latest version of the Linux operating system and so on. While it may take a little longer, the risk can be minimized.

I also take this strategy when upgrading the kernel of the system. If there are no critical applications deployed on the Linux operating system, or if the new servers are redeployed, I am downloading the latest Linux version of the operating system from the network. Even before this, there was a previous version of the Linux operating system image. Although you can do this by installing an older version of the operating system, and then through the kernel upgrade. But that's not a good way to handle it.

To do this, I think the way to upgrade the kernel is also very important when upgrading it. In particular, it is important to note that kernel upgrades through patch files can improve the flexibility of kernel upgrades to some extent. However, unless the system administrator is very confident about themselves, it is best not to use this method of kernel upgrade work.

Third, confirm the existing hardware configuration

The biggest difference between the Linux operating system and the Windows operating system is the compatibility of the hardware. Typically, hardware change information is automatically monitored under the Windows operating system. When the hardware changes, the Windows operating system automatically adjusts. However, the Linux operating system is different. While the latest version of the Linux operating system has been very friendly to most of the hardware on the market. However, there is still a lot of hardware that needs to be set by the system administrator. such as the use of different interface mouse or different keys number of mouse, the system administrator needs to manually set up before they can use. These configuration information may be lost after the kernel upgrade is successful. After the kernel is upgraded, these hardware may fail to be used. So often after the kernel upgrade, you need to manually configure some of the hardware.

To reduce the hassle of subsequent configurations, the system administrator needs to understand the existing hardware configuration of the Linux operating system and query the system resources, such as IRQ, used by each hardware. Only then can the system administrator be able to quickly utilize the previous configuration information to resolve the failure problem after the system upgrade, in case some hardware is not available or unrecognized, thus reducing the time of the Linux operating system. Typically, this is important for the Linux operating system as a server system.

Finally, we emphasize the principle of a system kernel upgrade. If the Linux operating system is used as a client, it is convenient to reinstall the latest version of the Linux operating system directly unless there is a special need. Only those operating systems that have more complex application services installed are done through the system kernel upgrade. For example, the mailbox service system has been deployed in the Linux operating system. Because of the need to install an Oracle database system, a later version of the kernel is required. If you upgrade the kernel version of the Linux operating system by reinstalling the Linux operating system, you will need to redeploy the mailbox service system, which may take more time. In this case, it is reasonable to meet the needs of the Oracle database application installation by means of a kernel upgrade.

Linux system administrator: Don't be afraid to upgrade the kernel