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How to configure sysctl.conf files to optimize the system, in view of this problem, this article introduces the corresponding analysis and solutions in detail, hoping to help more partners who want to solve this problem to find a more simple and easy way.

Guided Sysctl is a powerful tool for dynamically modifying kernel parameters while the kernel is running. With the help of this command, kernel parameters can be modified without having to recompile the kernel or restart the system.

Parameters that can be modified can be found in the / proc/sys directory. Therefore, procfs (file system emulation that can communicate with the kernel through the file system) is required for "sysctl". Only root users can execute this command.

Use the sysctl command to modify kernel parameters

Kernel parameters can be modified temporarily or permanently. The temporary modifications to the kernel parameters are as follows:

Read the parameters of the current kernel:

[root@localhost] # sysctl-a

Use-w to temporarily modify kernel parameters. For example, disable other devices from ping native:

[root@localhost ~] # sysctl-w net.ipv4.icmp_echo_ignore_all=1net.ipv4.icmp_echo_ignore_all = 1

A value of "0" represents "off" and a value of "1" represents "on". These changes are temporary, reset the parameters after rebooting the system.

Permanently modify kernel parameters

Add parameters and values to the / etc/sysctl.conf file, for example, disable other devices native ping, and after modifying the sysctl.conf configuration file, you need to execute the sysctl-p command to load the sysctl settings from the file / etc/sysctl.conf file. :

[root@localhost ~] # echo "net.ipv4.icmp_echo_ignore_all = 1" > > / etc/sysctl.conf [root@localhost ~] # sysctl-pnet.ipv4.icmp_echo_ignore_all = 1

Several examples of sysctl usage

Control packet forwarding

IP packet forwarding is enabled only on the server that acts as the gateway. You can disable this feature on other servers.

[root@localhost ~] # echo "net.ipv4.ip_forward = 0" > > / etc/sysctl.conf [root@localhost ~] # sysctl-pnet.ipv4.icmp_echo_ignore_all = 1net.ipv4.ip_forward = 0

Deactivate swap partitions

When using the kubernetes environment, you need to turn off the swap partition for performance reasons.

[root@localhost ~] # echo "vm.swappiness = 0" > > / etc/sysctl.conf [root@localhost ~] # sysctl-pnet.ipv4.icmp_echo_ignore_all = 1net.ipv4.ip_forward = 0vm.swappiness = 0

SYN flood control

To prevent SYN Flood attacks, you need to turn this on.

[root@localhost ~] # echo "net.ipv4.tcp_syncookies = 1" > > / etc/sysctl.conf [root@localhost ~] # sysctl-pnet.ipv4.icmp_echo_ignore_all = 1net.ipv4.ip_forward = 0vm.swappiness = 0net.ipv4.tcp_syncookies = 1

Range of ports allowed to be opened by the system

[root@localhost ~] # echo "net.ipv4.ip_local_port_range = 1024 65000" > > / etc/sysctl.conf [root@localhost ~] # sysctl-pnet.ipv4.icmp_echo_ignore_all = 1net.ipv4.ip_forward = 0vm.swappiness = 0net.ipv4.tcp_syncookies = 1net.ipv4.ip_local_port_range = 1024 65000

Sysctl is a powerful tool for dynamically modifying kernel parameters while the kernel is running. With the help of this command, kernel parameters can be modified without having to recompile the kernel or restart the system.

This is the answer to the question about how to configure the sysctl.conf file to optimize the system. I hope the above content can be of some help to you. If you still have a lot of doubts to be solved, you can follow the industry information channel to learn more about it.

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