If we find that our VPS server is abnormal, generally we can analyze it from the server logs to see if there is an IP source that does not follow the "rules". For example, we can use server log analysis tools: ngxtop and GoAccess to analyze the IP source, number of connections, error requests, browsers, traffic bandwidth, etc. in the statistical logs.
Summary of Linux system monitoring commands - master CPU, memory, disk IO, etc. to find performance bottlenecks
I don’t know if I used a VPS host with a high configuration before, or if there is a problem with the performance of the newly moved Alibaba Cloud Hong Kong VPS host. In short, every time I dig the site at night, the host becomes unstable and the system load suddenly becomes high. suddenly low. Using server log analysis tools: ngxtop and GoAccess, you can also find out that some IPs are constantly scanning server ports and WP background.
Free open source PHP probe x-prober and cool Linux server performance real-time monitoring tool Netdata
Many times, friends who engage in server maintenance hope to have a server performance monitoring platform that can provide an overall overview, so that they can grasp the running dynamics of the company's servers in real time. There are currently many third-party network performance monitoring platforms on the market, such as Alibaba Cloud, Tencent Cloud, Linode, Vultr and other VPS hosting providers with their own server performance monitoring services.