What is the function of restarting the server? Detailed explanation of the principle and applicable scenarios

in the long-term operation of the server, it is inevitable to encounter problems such as slow system response, abnormal program crash, configuration failure, etc. Many operation and maintenance personnel will choose to restart the server to solve it. But many people only know why, do not know the deep logic of restarting the server, and are not sure when to use this operation. This article will comprehensively dismantle the relevant knowledge of restarting the server from multiple dimensions such as principle, function, and applicable scenarios, and help everyone carry out server operation and maintenance work scientifically and standardized.

What is the underlying operating principle of restarting the server?

to understand the role of restarting the server, you must first understand its underlying operating logic, which is the basis for judging whether to restart.

1 Forced reset of system resources

server is running, CPU, memory, disk I/O and other hardware resources will be continuously occupied by various processes, and some abnormal processes may leak resources, resulting in resources not being released normally. Restarting the server will trigger the hard reset process of the system, forcing the termination of all running processes, returning all hardware resources to the system, and returning the resources to the initial available state.

2, system service reinitialization

server's various system services, such as network services, storage services, etc., may have problems such as configuration parameter offset and process deadlock during long-term operation. Restart the server will reload the configuration files of all system services according to the preset start sequence, initialize the service process, repair the abnormal state in the service operation, and ensure that the service starts to run with standard configuration.

3, kernel state cleaning refresh

server operating system is responsible for managing hardware resources and process scheduling. After long-term operation, the kernel may accumulate redundant information such as temporary data and error logs. Restarting the server will reload the kernel image, clean up the redundant data in the kernel, refresh the kernel state, and return the kernel to the optimal operation mode to improve the overall stability of the system.

2. What core problems can be solved by restarting the server?

restart the server is a common operation in operation and maintenance, its core value is to quickly solve all kinds of system and program abnormalities, the following comb several typical application scenarios.

1, Fix program exceptions and crash

when the application on the server does not respond, crash, infinite loop and other issues, some abnormal processes can not be terminated by conventional commands, then restart the server can be forced to close all abnormal processes, after the system restart is completed, then restart the normal application, quickly resume business operation.

2, release redundant system resources

server runs for a long time, the memory fragments will gradually increase, and the memory occupied by some processes cannot be recycled, resulting in a continuous decrease in available memory and a slower system response. Restarting the server will completely clean up the memory fragments, release the invalid occupied memory, CPU and other resources, and restore the server to its initial running performance.

3, effective new system configuration

modify the server's system parameters, network configuration, service configuration, some configuration can not take effect in real time, must restart the server to reload the configuration file, so that the new configuration overwrites the old configuration, to ensure that the system and services run according to the new rules.

What are the applicable scenarios for restarting the server?

restart the server is not a universal solution, it needs to be used reasonably in combination with the actual operation and maintenance scenarios to avoid unnecessary business interruption.

1, regular maintenance in routine operation and maintenance

for servers carrying non-core business, you can develop a regular restart server operation and maintenance plan, such as monthly or quarterly restart, timely cleaning system remnant inventory, prevent performance degradation and abnormal problems caused by long-term operation, and maintain the stable operation of the server.

2, emergency repair after sudden failure

when the server system blue screen, the network is completely interrupted, the core service collapse and other serious failures, and through routine investigation can not quickly locate the solution, restart the server is the most direct means of emergency repair, can try to restore the server in the shortest time basic operation ability.

3. Effective operation after configuration update

after completing the system version upgrade of the server, hardware driver update, core service configuration modification and other operations, if the relevant configuration prompts need to be restarted, you must perform the operation of restarting the server to ensure the normal operation of the new configuration and new functions.

What are the security precautions for restarting the server?

restarting the server will cause a short interruption of business, improper operation may also lead to data loss and other risks, so it is necessary to follow certain security norms.

1, do data backup in advance

before restarting the server, the core business data and configuration files on the server must be backed up to avoid problems such as power interruption and system abnormality during the restart process, resulting in data loss or damage and affecting the normal recovery of the business.

2, choose the appropriate operating time

restarting the server will interrupt business services, so choose a low-peak business period to operate, such as early morning or weekends, to reduce the impact on users. At the same time, it is necessary to issue notices in advance to inform relevant business personnel and users to prepare for business interruptions.

3, try soft restart operation first

restart the server is divided into soft restart and hard restart. Soft restart is an orderly restart triggered by system commands. It will shut down all processes and services normally before restarting the system. Hard restart is to directly cut off the power or press the restart button, which can easily lead to data loss. Therefore, soft restart is preferred, and hard restart is only considered when the soft restart fails.

To sum up, restarting the server is an indispensable operation in server operation and maintenance. It fixes abnormalities and optimizes performance by resetting system resources and initializing service processes. It is suitable for scenarios such as regular maintenance, fault emergency and configuration taking effect. When performing restart server operations, follow safety specifications and make preparations in advance to ensure the safety and effectiveness of the operation. Reasonable use of restart servers can effectively improve the efficiency of server operation and maintenance and ensure the stable operation of the business.