Introduction to Nginx log management

Nginx log description

Through access logs, you can get relevant information such as user geographical origin, jump source, terminal used, number of visits to a certain URL, etc.; through error logs, you can get the performance bottleneck of a certain service or server in the system, etc. Therefore, if you make good use of the log, you can get a lot of valuable information.

Parameter list:

Nginx log separation

Nginx's log files do not have a rotate function. To generate a log every day, we can write an nginx log cutting script to automatically cut the log file.

The first step is to rename the log file. Don’t worry about losing the log file because nginx cannot find the log file after renaming. Before you reopen the log file with the original name, nginx will still write logs to the file you renamed. Linux locates files by file descriptors rather than file names.

The second step is to send the USR1 signal to the nginx main process. After receiving the signal, the nginx main process will read the log file name from the configuration file, reopen the log file (named after the log file in the configuration file), and use the user of the working process as the owner of the log file. After reopening the log file, the nginx master process will close the log file with the same name and notify the worker process to use the newly opened log file. The worker process immediately opens the new log file and closes the log file with the same name. Then you can process the old log files. [Or restart the nginx service].

Nginx log format

Open the nginx.conf configuration file: vim /usr/local/nginx/conf/nginx.conf
Check Nginx's nginx.conf file and you can see this message

#access_log logs/access.log main;

This means that the server access log file is logs/host.access.log, and the format used is "main".
The log is generated to the logs/access.log file in the Nginx root directory. The "main" log format is used by default, and a custom format can also be used.

main format

#log_format main '$remote_addr - $remote_user [$time_local] "$request" '
# '$status $body_bytes_sent "$http_referer" '
# '"$http_user_agent" "$http_x_forwarded_for"';
#Parameter explanation $remote_addr client IP address;
$remote_user client username;
$time_local The time and time zone of the access;
$request The type of access request, POST or GET;
$status records the request status, 404, 304, 200, etc.;
$body_bytes_sent: the size of the file body content sent by the client to the server;
$http_referer Access source - from which link;
$http_user_agent User agent information, usually a browser tag, sometimes also a crawler tag.
$http_x_forwarded_for Directly access the IP address of the server, which may be the client IP or the proxy server IP
#Apply the main format log instance 47.97.66.214 - - [05/May/2018:02:18:26 +0800] "GET /solr/ HTTP/1.1" 404 571 "http://44.186.245.237/solr/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, li Gecko) Chrome/59.0.3071.115 Safari/537.36"
47.97.66.214 - - [05/May/2018:02:18:26 +0800] "GET /wcm/ HTTP/1.1" 404 571 "http://44.186.245.237/wcm/" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, li Gecko) Chrome/59.0.3071.115 Safari/537.36"
80.82.78.50 - - [05/May/2018:03:53:56 +0800] "GET http://www.baidu.com/ HTTP/1.1" 404 169 "-" "Mozilla"
112.193.171.197 - - [05/May/2018:06:52:06 +0800] "GET http://www.rfa.org/ HTTP/1.1" 200 462 "-" "python-requests/2.6.0 CPython/2.7.5 Linux/3.10.0-693.11.1.el7.x86_64"

In addition to the main format, you can customize other formats by recombining the above parameters.

The default log of nginx is stored in logs/access.log , but it is also possible to make different logs for different servers. Just add the following statement under the corresponding server

access_log logs/access_8080.log mylog;
#Declare a log #Log storage directory and name #Log format (customizable)

After modifying nginx.conf, you need to restart Nginx for the configuration to take effect

Summarize

The above is the full content of this article. I hope that the content of this article will have certain reference learning value for your study or work. Thank you for your support of 123WORDPRESS.COM. If you want to learn more about this, please check out the following links