My laptop’s hard drive crashed. I went to someone else and got the hard drive replaced, but they could not recover my data. You may try PhotoRec as for https://www.systutorials.com/qa/1399/how-can-i-recover-deleted-photos-from-samsung . Although its named with “Photo”, PhotoRec can recover many kinds of files as listed in http://www.cgsecurity.org/wiki/File_Formats_Recovered_By_PhotoRec .
Author: Eric Ma
Eric is a systems guy. Eric is interested in building high-performance and scalable distributed systems and related technologies. The views or opinions expressed here are solely Eric's own and do not necessarily represent those of any third parties.How to check whether a USB disk is connected to a Linux server?
Posted onI can only connect to a Linux server by SSH. How to check whether a USB disk is connected to the Linux server? 2 ways I usuaully use: Method One: Check the print out of dmesg After the USB storage is connected and detected by Linux, it may print some messages containing “[sde]” (the new
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Good tutorials for screen on Linux
Posted onAny suggestions on good tutorials for screen on Linux? To start with screen: A quick tutorial on screen. After can use the basic functions of screen, you may check out A dummies introduction to GNU Screen and A guide to GNU Screen. During all the progresses, frequently check the screen man page.
How to convert all text from upper case to lower case on Linux?
Posted onHow to convert all text in a file from upper case to lower case and vice versa on Linux? Convert from upper case to lower case: tr ‘[:upper:]’ ‘[:lower:]’ < input.txt > output.txt Convert from lower case to upper case: tr ‘[:lower:]’ ‘[:upper:]’ < input.txt > output.txt
How to avoid mounting failures blocking Linux booting?
Posted onSome entries in /etc/fstab may not not critical for booting Linux or even not available until Linux has booted. How to avoid the failures or unavailability of some mounting entries in /etc/fstab blocking the boot process of Linux? Please check the tutorial at Controlling Filesystem Mounting on Linux by Playing with /etc/fstab: Allow non-root users
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How to merge multiple PDF files to a PDF on Linux?
Posted onconvert seems works not very well when merging PDFs. The quality is low. Any other better methods to merge multiple PDF files to a single PDF on Linux? ghostscript works the best for me on merging PDFs: gs -q -sPAPERSIZE=letter -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -dPDFSETTINGS=/prepress -sOutputFile=out.pdf in1.pdf in2.pdf in3.pdf merges in{1..3}.pdf to out.pdf.
How to email admins automatically after a Linux server starts?
Posted onManaging a cluster of servers, I would like to notified when a server is started. How to make the Linux servers email me or other admins automatically after they are started? I did this by adding a crontab entry on each servers like @reboot date | mailx -S smtp=smtp://smtp.example.com -s “`hostname` started” -r zma@example.com zma@example.com
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How to make Linux automatically reboot after a kernel panic?
Posted onAfter a kernel panic, it is impossible to remotely connect to the Linux server to reboot it by SSH. How to make the panic kernel automatically reboot itself? Linux kernel has a nice feature that reboots itself after a timeout when a kernel panic happened. Usually, it is disabled by default. To turn it on,
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how to skip mapper function in hadoop
Posted onIn hadoop I need to skip mapper function and directly execute the reducer function. We doing this to improve hadoop performance, if the hadoop framework is used to analyze same data sets, then mapper’s output will be same for different kind of jobs. To save the redundant computation for same results, I am planning to
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How to get files without certain strings in their files names (reverse of *string*) on Linux?
Posted onTo get files with certain string in their file names, it is quite straightforward: ls *string* However, how to do the reverse one: how to get files without certain strings in their files names on Linux? You can get a list of file names by a combination of find and xargs as follows: find .
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How to set replication factors for HDFS directories?
Posted onIs it possible to set the replication factor for specific directory in HDFS to be one that is different from the default replication factor? This should set the existing files’ replication factors but also new files created in the specific directory. This can simplify the administration. We can set the replication factor of /tmp/ to
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How to make CentOS 6.6 power off the console screen automatically?
Posted onOn CentOS 6.6, I find that it can make the screen (console, not X) blank after a while. However, it does not power the screen off. This usually work on Fedora or other releases. I guess this is caused by some configurations specific in CentOS 6.6. How to make CentOS 6.6 power off the console
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How to install vbetool on CentOS 6.6?
Posted onI found CentOS 6.6 does not ship vbetool in its default repositories, EPEL or RPMfusion. How to install vbetool on CentOS 6.6? First, download the source package from http://www.codon.org.uk/~mjg59/vbetool/ and unpack the package. Second, install needed packages: # yum pciutils-devel pciutils-devel-static libx86-devel During the building, it will try to find the libpci.a in a different
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How to enable RPM Fusion for CentOS 6.6?
Posted onHow to enable RPM Fusion for CentOS 6.6? Enable RPM fusion on RHEL 6 or compatible like CentOS: su -c ‘yum localinstall –nogpgcheck http://download1.rpmfusion.org/free/el/updates/6/i386/rpmfusion-free-release-6-1.noarch.rpm http://download1.rpmfusion.org/nonfree/el/updates/6/i386/rpmfusion-nonfree-release-6-1.noarch.rpm’ It will install https://fedoraproject.org/wiki/EPEL. If it fails to install EPEL automatically, you will need to install it manually. Reference: http://rpmfusion.org/Configuration
Deleting a Specific Line From a Text File in Command Line in Linux
Posted onOn Linux, how to delete a specific line from a text file in command line? For example, to delete the 4th line from a file aaa bbb ccc ddd eee ffffff You can use the “stream editor for filtering and transforming text” sed. With GNU sed: sed -i ‘4d’ ./file Here, -i means edit the
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How to convert .pptx slides to .jpg or .png images on Linux in command line?
Posted onHow to convert .pptx slides to .jpg or .png images on Linux in command line? This following method works best for me. First, convert .pptx file to .pdf using libreoffice: libreoffice –headless –convert-to pdf file.pptx –headless makes libreoffice run in batch mode and not start the GUI. The pdf file will be named file.pdf by
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How to install musl libc on Fedora 21 Linux?
Posted onIt seems Fedora 21 does not ship with musl-libc. How to install musl libc on Fedora 21 Linux? First, download musl libc source package from its download page: http://www.musl-libc.org/download.html . Here we use 1.1.5 as the example. After unpacking the source package, configure and build it by $ ./configure $ make Then, install it by
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How to build mplayer with libdvdnav on Linux?
Posted onI find the mplayer from rpmfusion does not contain libdvdnav. How to build mplayer with libdvdnav on Linux? I did this on Fedora 21 to build mplayer with libdvdnav: Download mplayer src from http://www.mplayerhq.hu/design7/dload.html and extract the tarball. Install needed packages (you will need more if you need more features): # yum install gcc make
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How can I recover deleted photos from samsung?
Posted onHow can I recover deleted photos from samsung? You may try PhotoRec. A step by step tutorial can be found here. There are similar software. You can google them. Have you retrieved your lost photos from Galaxy? If not, you can follow the steps below to get some back. Hope it helps you somewhat. Stop
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When should the authors anonymize themselves in a paper submitted to a conference for review?
Posted onWhen should the authors anonymize themselves in a paper submitted to a conference for review? Several general concepts: Peer review is the evaluation of work by one or more people of similar competence to the producers of the work (peers). — Wikipedia Single-blind describes experiments where information that could introduce bias or otherwise skew the
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