Prefix Substitution with http:
The request line contains a great deal of useful information. First, the method used by the client is GET. It is also possible to log one or more parts of the request line independently. This information is very valuable, because it reveals whether the request resulted in a successful response codes beginning in 2a redirection codes beginning in 3an error caused by the client codes beginning in 4or an error in the server codes beginning in 5.
If no content was returned to the client, this value will be "-". Another commonly used format string is called the Combined Log Format.
It can be used as follows. The access log under this format will look like: This gives the site that the client reports having been referred from. This is the identifying information that the client browser reports about itself.
Multiple Access Logs Multiple access logs can be created simply by specifying multiple CustomLog directives in the configuration file. For example, the following directives will create three access logs.
The first contains the basic CLF information, while the second and third contain referer and browser information. Instead, the log format can be specified directly in the CustomLog directive. Conditional Logs There are times when it is convenient to exclude certain entries from the access logs based on characteristics of the client request.
This is easily accomplished with the help of environment variables. First, an environment variable must be set to indicate that the request meets certain conditions.
This is usually accomplished with SetEnvIf. A very simple method to find this out would be: In that case a cache hit will log - while a cache miss will log 1. In other cases, a literal "-" will be logged instead. Likewise, in the second example, the Referer will be logged if the HTTP status code is not, or Although we have just shown that conditional logging is very powerful and flexible, it is not the only way to control the contents of the logs.
Log files are more useful when they contain a complete record of server activity. It is often easier to simply post-process the log files to remove requests that you do not want to consider.
Log Rotation On even a moderately busy server, the quantity of information stored in the log files is very large. The access log file typically grows 1 MB or more per 10, requests. It will consequently be necessary to periodically rotate the log files by moving or deleting the existing logs.
This cannot be done while the server is running, because Apache httpd will continue writing to the old log file as long as it holds the file open. Instead, the server must be restarted after the log files are moved or deleted so that it will open new log files. By using a graceful restart, the server can be instructed to open new log files without losing any existing or pending connections from clients.
However, in order to accomplish this, the server must continue to write to the old log files while it finishes serving old requests. It is therefore necessary to wait for some time after the restart before doing any processing on the log files. A typical scenario that simply rotates the logs and compresses the old logs to save space is:Embed the Power of Lua into NGINX HTTP servers.
Contribute to openresty/lua-nginx-module development by creating an account on GitHub. The full HTTP request line sent by the browser to the server (e.g., "GET /leslutinsduphoenix.com HTTP/"). This does not include any additional headers sent by the browser. This does not include any additional headers sent by the browser.
The server access log records all requests processed by the server. The location and content of the access log are controlled by the CustomLog directive. The LogFormat directive can be used to simplify the selection of the contents of the logs.
This section describes how to configure the server to record information in the access log. What is the difference in terms of functionality between the Apache HTTP Server and Apache Tomcat?
I know that Tomcat is written in Java and the HTTP Server is in C, but other than that I do not really know how they are distinguished. A practical guide to secure and harden Apache Web Server.
1. Introduction. The Web Server is a crucial part of web-based applications. Apache Web Server is often placed at the edge of the network hence it becomes one of the most vulnerable services to attack. We all are very familiar with Apache web server, it is a very popular web server to host your web files or your website on the web.
Here are some links which can help you to configure Apache .