How to set up proxy auto config on Ubuntu Desktop

Suppose you are using your Ubuntu Desktop laptop at home and workplace. Assume that when you are at your workplace, the corporate network your laptop is connected to is behind proxy. You then have to turn on/off proxy depending on where you are. Of course you can manually update proxy settings of Ubuntu Desktop every time your network changes, but that's quite cumbersome. That's when proxy auto-config helps.Read more »

How to enable logging in OpenStack via devstack

Devstack is a shell script used to automate the building process of the entire OpenStack development environments. In OpenStack deployment created by devstack, debug output of individual OpenStack services goes to their corresponding interactive screen sessions. For debugging purposes, however, you may want to enable logging in OpenStack services. If you are using devstack to install OpenStack, you can easily enable logging in OpenStack by using devstack.Read more »

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, while it's necessary to intercept client's requests.Read more »

How to use a custom DNS server on Ubuntu Desktop

In Linux, DNS servers are specified in /etc/resolv.conf. However, a proper way to configure custom DNS settings on Ubuntu Desktop is not manually modifying /etc/resolv.conf, but using a separate GUI-based network management program which controls the content of /etc/resolv.conf.Read more »

How to find the IP address of VMware virtual machine

When you run a virtual machine (VM) created by VMware Player or VMware Server, there can be circumstances where you don't have console access to the VM. For example, you could be running your VM without VMware Player GUI, or you may have trouble opening a remote console from VMware Server. If you don't have access to VM console, you will need to remotely ssh to the VM by using its IP address. But how do you find out its IP address in the first place?Read more »

How to manage a wired network on Ubuntu Desktop

On Ubuntu Desktop, a separate GUI program called NetworkManager is responsible for configuring network settings (e.g., wired network, wireless network, proxy settings). However, on a fresh installation of Ubuntu Desktop, your wired network is NOT managed by NetworkManager, but by /etc/network/interfaces.Read more »

How to backup a hard disk on Linux

If you would like to backup your hard disk, there is a simple way to do it by using "dd" command. The dd command utility is used to copy files or disk images from one location to another. Using dd, you can backup an unmounted disk as a (compressed) disk image which is then stored in a separate local or remote disk. Here is how to backup and restore a hard drive using dd command.Read more »

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.Read more »

How to configure http proxy exceptions on Linux

When you are behind http proxy, you need to configure proxy settings for your applications in one way or another. Typically you define http_proxy environment variable pointing to your proxy, so that all http requests go through the proxy. But what if you want to bypass http proxy for specific destination web servers? That's when you need to configure http proxy exceptions.Read more »

How to diff remote files over ssh

Diff command line utility compares contents of two files (or directories), and shows how they differ line by line. It's straightforward to use diff if both input files are located on local host. But what if input files located on two different hosts? You can actually diff remote files over ssh. Here is how.Read more »