Any 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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Category: Tutorial
Git: changing global user name and user email
Posted onHow to set the global user name and user email for git? We may be asked to set our global user name and user email if it is the first time that we use git on a machine: Your name and email address were configured automatically based on your username and hostname. Please check that
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How to find Linux absolute path for a relative path
Posted onHow to find Linux absolute path for a relative path in Linux? We may need the absolute path on Linux when we only know the relative path. The readlink command does the trick. To find out the absolute path for a relative path, e.g. ./: $ readlink -f ./
Large-but-correctly-aligned-and-optimized code is faster than less-bytes-per-instruction/opcode-packed code
Posted onIs large-but-correctly-aligned-and-optimized code faster than less-bytes-per-instruction/opcode-packed code? Alex Ionescu mentioned in ros-dev mailing list: I’m not sure why you would want kernel code to be “smaller” instead of “faster” though — on modern processors for cases like interrupts and such, large-but-correctly-aligned-and-optimized code is faster than less-bytes-per-instruction/opcode-packed code. ie: mov eax, [foo] add eax, 1 mov
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SEEK_HOLE and SEEK_DATA: efficiently archive/copy large sparse files
Posted onHow to efficiently archive a very large sparse file, say 1TB? The sparse file may contains a small amount of data, say 32MB. SEEK_HOLE and SEEK_DATA The SEEK_HOLE/SEEK_DATA functionalities play the trick and makes `tar` and `cp` handle the large sparse file very efficiently. `lseek` with `SEEK_HOLE` returns the offset of the start of the
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How to search bad blocks on a device?
Posted onIf I have a disk with bad blocks, how to search bad blocks on it under Linux? You can use ‘badblocks’: https://www.systutorials.com/docs/linux/man/8-badblocks/ badblocks [ -svwnf ] [ -b block-size ] [ -c blocks_at_once ] [ -e max_bad_blocks ] [ -d read_delay_factor ] [ -i input_file ] [ -o output_file ] [ -p num_passes ] [
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How to install the MATE fork of Gnome 2 on Fedora 17?
Posted onI miss Gnome 2. How to install the MATE fork of Gnome 2 on Fedora 17? MATE is already included into Fedora 17’s repository and is an official feature of Fedora 18. To install MATE on Fedora 17 # yum install @mate-desktop To install softwares usually needed: # yum install mate-media mate-screensaver mate-system-monitor mate-power-manager mate-utils
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Mmaping Memory Range Larger Than the Total Size of Physical Memory and Swap
Posted onIn Linux, mmap() is a system call that is used to map a portion of a file or device into the memory of a process. This can be useful for a variety of purposes, such as memory-mapped I/O, shared memory, and virtual memory management. However, when mapping a large range of memory that is larger
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How to find hard links to a file
Posted onHow to find hard links to a file in Linux? To find out all hard links to file1: $ find /home -xdev -samefile file1 Read more: http://linuxcommando.blogspot.com/2008/09/how-to-find-and-delete-all-hard-links.html
Managing LVM
Posted onAny tutorials or tips on how to manage LVM? LVM provides a flexible and easy way to management storage disks on Linux. It also provides a set of tools for management. Here are some tutorials and references for managing LVM: LVM man pages: https://www.systutorials.com/docs/linux/man/8-lvm/#lbAL Manage Disk Volume in Linux: http://www.hongkedavid.com/blog/disk_volume.html LVM with Xen: https://www.systutorials.com/b/linux/tag/lvm/ Remove missing phyiscal volumes
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How to test the connections between Linux hosts/servers?
Posted onHow to easily and quickly test the connection between two nodes on Linux? This should be specific to protocol and port. We can use nc (netcat) to test the connection between two servers. For example, to test whether TCP port 1048 can be used on the server (IP 10.0.3.48 as an example) side: On the server: $
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Where Does Evolution Save Its Data and Configuration Files on Linux?
Posted onEvolution is a great personal information management tool that provides Email, address book and calendar tools. Evolution provides many enterprise friendly feature such as native support to Microsoft Exchange connectivity for Emails, address books and calendars. Evolution uses various ways including plain files and dconf configuration systems. This post will give an introduction to the
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How to Export an NFSv4 Server to External Networks
Posted onWe ever discussed fixing ports used by NFSv3 so that it can be easily exported to external networks. For NFSv4.1 or higher, things are much easier. The ports for mountd, statd, and lockd are not required in a pure NFSv4 environment. We have less ports to control or allow for connections. Only port 111 and
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How to Add Custom Content on a Receipt
Posted onThis blog will explain about how to add a custom content in a Receipt which will be generated from MPOS in Microsoft Dynamics. Microsoft provides us with certain fields which can be put into the receipt. There are certain fields which a client will ask to show in the receipt. If the desired field is
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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 Implement Hibernate Envers in an Application
Posted onTechnology Hibernate Envers is the frameworks for auditing entities. As the name suggests Hibernate Envers is developed on top of Hibernate, it will on Hibernate and Hibernate implemented JPA. Hibernate Envers provides easy auditing, versioning solution for entity classes. Advantages of Hibernate Envers: Auditing of all mappings defined by JPA specification. Auditing Hibernate specific mappings
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Deploying ASP.NET Core 2.0 MVC application to Azure Web apps using Visual Studio 2017
Posted onIntroduction In this tutorial, we will be learning as how to deploy .NET Core 2.0 MVC web application on Microsoft Public Cloud i.e. Microsoft Azure, using Microsoft Visual Studio 2017 v15.3 For novice Cloud developers, aspiring .NET / Cloud architects, and all other IT professionals associated with the .NET Core framework & Cloud computing, especially
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A Beginners’ Guide to x86-64 Instruction Encoding
Posted onThe encoding of x86 and x86-64 instructions is well documented in Intel or AMD’s manuals. However, they are not quite easy for beginners to start with to learn encoding of the x86-64 instructions. In this post, I will give a list of useful manuals for understanding and studying the x86-64 instruction encoding, a brief introduction
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How to force a metadata checkpointing in HDFS
Posted onThe metadata checkpointing in HDFS is done by the Secondary NameNode to merge the fsimage and the edits log files periodically and keep edits log size within a limit. For various reasons, the checkpointing by the Secondary NameNode may fail. For one example, HDFS SecondaraNameNode log shows errors in its log as follows. 2017-08-06 10:54:14,488
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How To Debug Linux Kernel With Less Efforts
Posted onIntroduction In general, if we want to debug Linux Kernel, there are lots of tools such as Linux Perf, Kprobe, BCC, Ktap, etc, and we can also write kernel modules, proc subsystems or system calls for some specific debugging aims. However, if we have to instrument kernel to achieve our goals, usually we would not
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