How to efficiently print a webpage? E.g. I want to only print the text for some pages but with figures for some other pages. I tried to copy the webpage to a document, but the format turns to be just terrible. One good tool that I use is PrinterFriendly which can convert a webpage to
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Tag: SSH
How to activate or deactivate a Linux host with Gnome remotely?
Posted onI have a Fedora Linux server with Gnome 3. I want to lock / unlock the remote Gnome desktop remotely. How to activate or deactivate it remotely through SSH? Use gnome-screensaver-command. It is not specific to Gnome 3. Turn the screensaver on (blank the screen): $ gnome-screensaver-command -a If the screensaver is active then deactivate
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How to set up proxy over SSH on Windows?
Posted onThis tutorial teaches how to set up SSH proxy on Linux. How to set up one proxy over SSH on Windows? A tutorial of using SSH tunnel as the proxy on Windows is introduced here: https://www.systutorials.com/tutorial/4696/software/proxy-using-ssh-tunnel-on-windows/
Howto: ssh automatically add new hosts to the list of known hosts
Posted onWhen managing many hosts, answering 100s of “yes” can make us crazy. In a trusted environment, let ssh automatically add the new hosts to the list of known hosts and free us from typing “yes”es. How to enable it? Method 1. Passing option to ssh ssh -o StrictHostKeyChecking=no username@host Method 2. Configuring ~/.ssh/config To automatically
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Pass-less ssh auto-login problem
Posted onI configured the Linux password-less automatic ssh login as in this post . However, it still does not work for me. Any method to check it? The log in log /var/log/secure may give some clue on it. For example: Aug 20 23:16:10 doppler sshd[11143]: Authentication refused: bad ownership or modes for directory /home/useraaa tells us that
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Run Firefox on Remote Host over SSH
Posted onHow to run Firefox on Remote Host over SSH ? After $ ssh -X remotehost Run this script on remote host: #!/bin/bash export $(dbus-launch) export NSS_USE_SHARED_DB=ENABLED firefox -no-remote & This script credits to Waxborg: http://waxborg.servepics.com/opensuse/remote-administration/running-firefox-remotely-over-ssh.
Synchronizing home directories
Posted onAny good tools to synchronize home directories on Linux boxes? Many have several PC/laptops and consequently many home directories. There is home directory synchronizing problem. unison is a good tool to do this: http://www.cis.upenn.edu/~bcpierce/unison/download/releases/stable/unison-manual.html#rshmeth http://www.watzmann.net/blog/2009/02/my-homedirs-in-unison.html http://www.cis.upenn.edu/~bcpierce/papers/index.shtml#File%20Synchronization Useful script: $ unison -batch -ui text ./ /mnt/homebak/zma/ In text user interface, synchronizing two directories in batch mode
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A List of Common Software on Windows
Posted onQuick links to some useful software on Windows including Web browsers, Video/audio player and ssh/scpsftp/vnc tools for connecting to Linux. ssh/scp/sftp/vnc for connecting to Linux For Linux users, it is sometimes unavoidably to use Windows. With Windows, the Linux users will need to connect to Linux for some tasks. Some general software are needed. The
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How to Change Linux Account Password Through SSH: A Beginners’ Tutorial
Posted onPeople are sometimes given access to Linux/Unix and asked to change their initial passwords. But for beginners, changing a Linux/Unix password is not an easy task, especially when there is only SSH log on allowed to the Linux/Unix server. This post introduces how to change password of user USER on host HOST remotely using SSH.
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Forcing Linux to Unmount a Filesystem Reporting “device is busy”
Posted onLinux may report “device is busy” when we try to umount a filesystem. This behavior is reasonable as it can help us avoid data loss by disallowing unmouting a filesystem when it is being used. But for situations when we are sure there is something wrong happened or we care not data lost such as
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How to Disable and Enable Laptop Keyboard for X.org Server in Linux
Posted onAttaching a USB keyboard to a laptop is common when using a laptop because a normal keyboard may provide a more convenient typing experience. The laptop keyboard is not used in these situations. However, the laptop keyboard may still be touched by accident. In this post, we will discuss how to disable and enable the
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Three Methods of Executing Commands on Many Nodes in Parallel via SSH on Linux
Posted onIt is common to execute commands on many nodes/hosts via SSH for managing a cluster of Linux servers. On Linux, there are many choices for this task. Generally, to run commands on many nodes, there are two modes: serial mode and parallel mode. In serial mode, the command is executed on the node one by
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Notes for Beginners of Software Development on Linux
Posted onLinux is a great platform for software development targeting servers or backends. In general, working on Linux is very productive. The problem that beginners on Linux face is the the learning curve is steep at the beginning. But believe me, after you get through the initial green steep learning step as in the figure below
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Keeping Linux SSH Session Alive from Disconnecting – Server and Client Side Fixes
Posted onSSH is a very common tool for Linux/Unix platforms. One annoying problem when using SSH is that the connection may get disconnected if the SSH connection is idle for some time under common configurations. Users may run an infinite loop like while true; do uptime; sleep 30; done when there is no work to be
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SSD Enabled For DreamHost Shared Hosting: Simple Performance Measurement
Posted onSSD is common for VPS and PaaS virtual machines for higher I/O performance. Now, it is coming to shared hosting too. DreamHost states that “Now with solid state drives (SSDs), our standard web hosting loads pages 200% faster”. We ourselves are happy to know this performance improvement with the price kept the same. Good work,
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Lazy Linux Admins Going to Server Rooms Less: Forced Reboot, Auto Reboot after Kernel Panic and Email Notification after Reboot
Posted onHaving to go the the server room to reset servers is the most headache thing for admins managing a cluster of Linux servers in a remote site. Either you can ping the server but can not ssh to it, or you even can not ping it. There are various reasons that may cause a Linux
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How to Play Movie from Remote Host using MPlayer over SSH
Posted onMPlayer is a great movie player. SSH is a great tool to connect and transfer data over the network securely. Combining these 2 great tools together will be greater. You may already has a small server storing some movies or videos or music and playing them on your laptop will be convenient. In this post,
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Hadoop Installation Tutorial (Hadoop 2.x)
Posted onHadoop 2 or YARN is the new version of Hadoop. It adds the yarn resource manager in addition to the HDFS and MapReduce components. Hadoop MapReduce is a programming model and software framework for writing applications, which is an open-source variant of MapReduce designed and implemented by Google initially for processing and generating large data
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Git through SSH Tunnel as Proxy
Posted ongit is a great tool and it is common to have a git server over SSH possibly managed by gitolite. However, there are situations that we can not directly connect to the git server but be able to SSH to another node that can connect to the git server. The git server may allow only
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Directly SSH to Hosts’ Internal IPs Through the Gateway
Posted onWe have many hosts with internal/LAN IPs like 10.0.3.* behind a gateway and the hosts with LAN IPs can connect to the Internet through the gateway. We used iptables to forward port from the gateway to internal IPs so that users from hosts with Internet connections can SSH to the gateway’s forwarded port to log
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