How to analyze Squid logs with SARG log analyzer on CentOS

In a previous tutorial, we show how to configure a transparent proxy with Squid on CentOS. Squid provides many useful features, but analyzing a raw Squid log file is not straightfoward. For example, how could you analyze the time stamps and the number of hits in the following Squid log? 1404788984.429 1162 172.17.1.23 TCP_MISS/302 436 […]
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How to set up Squid as a transparent web proxy on CentOS or RHEL

In a previous tutorial, we have seen the method of creating a gateway using iptables. This tutorial will focus on turning the gateway into a transparent proxy server. A proxy is called “transparent” when clients are not aware that their requests are processed through the proxy. There are several benefits of using a transparent proxy. […]
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How to configure a Tomcat cluster on Ubuntu

Apache Tomcat is the most popular open-source Java web server. If your web site is expecting more traffic as your business grows, a single instance of Tomcat will probably not scale with the growing traffic. In that case, you might be thinking to run Tomcat in a “clustered” environment, where web server workload is distributed […]
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How to set up a transparent HTTPS filtering proxy on CentOS

HTTPS protocol is used more and more in today’s web. While this may be good for privacy, it leaves modern network administrator without any means to prevent questionable or adult contents from entering his/her network. Previously it was assumed that this problem does not have a decent solution. Our how-to guide will try to prove […]
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How to install .rpm packages behind proxy

RPM (RPM Package Manager) is a command-line utility for installing, removing, querying and updating .RPM packages for RedHat-based systems such as CentOS, RHEL or Fedora. Using rpm command, you can install a package from a locally downloaded .RPM file, as well as from a URL of a remotely available package. In this article, I will […]
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How to set up proxy auto config on Ubuntu Desktop

Suppose you are using your Ubuntu Desktop laptop at home and workplace. When you are at your workplace, the corporate network your laptop is connected to is behind proxy. You would then have to turn on/off proxy depending on where you are. Of course you could manually update proxy settings of Ubuntu Desktop every time […]
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How to set up a transparent proxy on Linux

A transparent proxy sits between clients and the Internet, acting as a gateway for the clients. It’s called transparent because clients are not required to configure anything for the proxy. A transparent proxy is useful when it’s not possible or desirable to modify client configurations, ant yet it’s still necessary to intercept client’s requests. If […]
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How to use svn behind proxy

If your Linux host is behind a corporate proxy, and you are trying to access a svn repository located outside the corporate network, you will need to configure proxy settings in svn, so that svn traffic can traverse the proxy properly. While most Linux applications that require network access respect http_proxy environment variable, subversion ignores […]
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