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Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.

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I am trying to clone this VM to another host and noticed it has 450GB allocated as "Thick Provisioned Lazy Zeroed"
On the OS level though I see only 188GB of this is actually used.
 I would like to reduce the disk size to say 300GB and then clone it but am not sure how to do this.
I think I need to use vMotion somehow but first wouldn't I need to make sure the data in the OS level is not located at the end of the disk?
Monthly Recap
Monthly Recap

May was a big month for new releases from Linux Academy! Take a look at what our team built recently in our blog. You can access the newest releases from our blog.

This is using an Amazon ami 64-bit EC2 instance. This is an web application server that do some routine registration. I am thinking of gathering and backing up some of the log files for further auditing purposes. please see the list of log files:


    Monitor default audit rules/custom audit rules


    Not entirely sure if I would be able to glean any intrusions/modification from this but this would give me an idea of the system state on start-up

/var/log/secure & /var/log/wtmp

    Authentication attempts/fails

"/var/log/httpd/ssl_error_log*" & "/var/log/httpd/ssl_access_log*"

    Access and error log for webpage (not sure if this would help holding onto these...but it could give an insight if a random IP kept hitting my webpage. Wouldn't prove anything but might warn?)

I am thinking of compress and backing up as an additional copy, let's say once every week. btw, please shed a light on how can I achieve this probably with the use of cron job?

Thanks in advance.
I restored a backup of my website and uploaded filers to my website folder /home/mywebsite/public_html using Bitvise FTP

The permissions for Owner ID & Group ID come up as 0 & 0, is there a Linux command to set Owner ID 515 & Group ID 526
I have a PowerEdge 2950 running Red Hat 6 - 64 that hosts a D3 Tigerlogic Multivalue Database. Been trying to P2V to create a VM for testing config changes. I've read dozens of online responses about the "No Operating System" error on the VM, but Linux is foreign to me and this server has a very complex history. Appears to have HARDWARE and SOFTWARE RAID and several mount points and Samba shares. I've tried the Red Hat DVD rescue fixes, but no go. Just don't understand what the bios is looking for on which partition to get it to boot. I believe all the partitions exist and are complete. Would really like an exact VM replica of the server. Going to try clonezilla booted off DVD next.
I've installed Jenkins on my Ubuntu machine running on compute engine in Google Cloud.

To do so I have run these commands:
sudo apt-get update
sudo apt-get install apache2 libapache2-mod-php5 php5-mcrypt php5-mysql git openjdk-7-jre openjdk-7-jdk -y
wget -q -O - | sudo apt-key add -
sudo sh -c 'echo deb binary/ > /etc/apt/sources.list.d/jenkins.list'
sudo apt-get update
sudo apt-get install jenkins

Open in new window

Jenkins seems to be installing fine but when i go to the public IP address on port 8080 there nothing there. I read that it may be so that Apache is using port 8080 so I edited /etc/default/jenkins and changed the port to 8081. Still I don't see jenkins on that port.

I've also restarted the service but no change there. If I do:

sudo netstat -plntu

Open in new window

I see:

Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0    *               LISTEN      422/sshd        
tcp        0      0    *               LISTEN      9745/apache2    
tcp6       0      0 :::22                   :::*                    LISTEN      422/sshd        
tcp6       0      0 :::8081                 :::*                    LISTEN      17917/java      
udp        0      0 *                        

Open in new window

I will buy a Windows 10 Home laptop with a 1 TB SSD, which I will begin with upgrading the OS to Windows 10 Pro.

But then I am unsure about how to partition the 1 TB SSD. I will use Hyper-V in the Pro version to run VMs (different Linux distributions I want to test, perhaps 10 of them). What would the best setup be for the partitions? On my current laptop (which has a 470 HDD), I have the programs installed on C: (195 GB) and data files on D: (270 GB). It has worked well. I have 45 GB free space on C:, and 67 GB free on D:

But now for this new computer I need a partition also for running VMs (if I should have a separate partition for that).

Besides running different Linux distributions  as VMs, I will also transfer my current laptop's contents to the new computer as a virtual machine by doing a clone of it.

Can I keep these different VMs on a flash drive like this (so I don't take up valuable space on the SSD)?:

SanDisk Ultra Fit 32 GB USB 3.0 Flash Drive

And then I use flash drives for the backup of the whole system also? But I need 1 clone (flash drive with VM) for each system, right? But how do I start each OS? Just insert the flash drive, or do I always have to start from the Windows 10 Pro, and switch to a VM from there?

What of what I have described above should be changed? And is it a good idea to only install Windows 10 Pro "permanently", and keep all the rest of the different OSs as VMs (what are the pros and cons between keeping an OS as …
I have xlc compiler version 8 and perl 5.10 running on AIX 7.1. I have been able to install module successfully, but now am in need to install DBD::ORACLE module. The oracle version is 12 (64bit)

perl Makefile.PL runs fine for the DBD::ORACLE module, however the "make" command is throwing below error:
I attempted to fix the issue by changing the object mode value, but that end up giving a different type of error.
Can you advise on the solution ?

        rm -f blib/arch/auto/DBD/Oracle/
        LD_RUN_PATH="/u01/app/oracle/product/12.1.0/client_1/lib:/u01/app/oracle/product/12.1.0/client_1/rdbms/lib" ld  -bhalt:4 -G -bI:/usr/opt/perl5/lib/5.10.1
            /aix-thread-multi/CORE/perl.exp -bE:Oracle.exp -bnoentry -lpthreads -lc -lm -L/usr/local/lib Oracle.o  dbdimp.o  oci8.o /lib/crt0_64.o -bI:/usr/lib/iocp.
            exp  -o blib/arch/auto/DBD/Oracle/     -L/u01/app/oracle/product/12.1.0/client_1/lib/ -lclntsh -lclntshcore -lld -lm -ldl -lc -lm -lpthreads -
            -lbsd_r -lld -lperfstat -lm -lpthreads
ld: 0711-736 ERROR: Input file /lib/crt0_64.o:
        XCOFF64 object files are not allowed in 32-bit mode.
make: The error code from the last command is 8.

#bootinfo -K

#ORACCENV='cc=xlc_r'; export ORACCENV

#export OBJECT_MODE=64
        rm -f blib/arch/auto/DBD/Oracle/
        LD_RUN_PATH="/u01/app/oracle/product/12.1.0/client_1/lib:/u01/app/oracle/product/12.1.0/client_1/rdbms/lib" ld  -bhalt:4 -G …
I recently upgraded AIX from 6.1 to 7.1, which resulted in perl getting upgraded from 5.8 to 5.10 as well and in process i no longer have a module under perl 5.10.

I have been unable to find binary version for for perl 5.10 so i am trying to compile it but running into an issue with it.
I am using steps of running perl Makefile.PL, make, make test, make install to compile.
I am able to successfully run perl Makefile.PL from the directory that i saved in /tmp from, but when i run the "make" command, i get following error.

Skip blib/lib/DBI/ (unchanged)
        xlc_r -q32 -c    -D_ALL_SOURCE -D_ANSI_C_SOURCE -D_POSIX_SOURCE -qmaxmem=-1 -qnoansialias -DUSE_NATIVE_DLOPEN -DNEED_PTHREAD_INIT -qlanglvl=extended -I/usr/local/include -q32 -D_LARGE_FILES -qlonglong -O    -DVERSION=\"1.636\"  -DXS_VERSION=\"1.636\"  "-I/usr/opt/perl5/lib/5.10.1/aix-thread-multi/CORE"   Perl.c
/bin/sh: xlc_r:  not found
make: The error code from the last command is 127.

I do have xlc compiler installed.
  vac.C              COMMITTED  IBM XL C Compiler
  vac.C              COMMITTED  IBM XL C Compiler
  vacpp.cmp.core     COMMITTED  IBM XL C/C++ Compiler
  vacpp.cmp.core     COMMITTED  IBM XL C/C++ Compiler
  xlC.aix61.rte     COMMITTED  IBM XL C++ Runtime for AIX 6.1

/usr/vacpp/bin/xlC -qversion
IBM XL C/C++ Enterprise Edition V8.0 for AIX
Version: …

I have a java program that writes out files in both Linux and Windows directories.

I unfortunately have to create file names that have a slash in them "/".

How do I create windows and Linux files with a forward slash "/" in them?

Here is an example of one of those file names: Test123/tst45#48


I was using an ORIGINAL document as a text file to learn Perl.  I screwed up the original and it will take me a couple days to retype it.  I've come to the conclusion that I can't trust myself to not screw up originals.  I want to add a program like subversion as another layer of protection.  I read I need to use a web server (???) to use subversion.  Am I getting involved in a big deal or is subversion good to install?
What is SQL Server and how does it work?
What is SQL Server and how does it work?

The purpose of this paper is to provide you background on SQL Server. It’s your self-study guide for learning fundamentals. It includes both the history of SQL and its technical basics. Concepts and definitions will form the solid foundation of your future DBA expertise.

We have a few windows servers a few linux - a few physical, but recently got a decently beefy vmware server and are running a handful of things on there.   We currently use Acronis but it is TERRIBLE...  mindbogglingly bad.  totally unreliable.... not even reliable to tell you when it's failing... it will have a nice big green "OK" next to servers that are NOT backed up.... sorry /rant.....

I want something RELIABLE... I want to set up the backups, and be able to rely they will happen or I will be notified, and preferably I dont have to intervene and have support try to fix things for hours every couple months.
Hi Dears,
I installed Flexible I/O Tester(FIO) from source in Centos 7,
now i want remove this package, but i dont find any command for remove from source,
can you help me, Please?

How to schedule a job to restart the server on Wed and Sat everyday at 4:00AM ?

I am running inotifywait to listen new files on a directory. The directory has 600 permission and user is vmail.
and I am running inotifywait using root user.

this is the command I used

inotifywait -mq -e CREATE --format %w%f /var/vmail/xxx/unsubscribe/cur | while read FILE; do echo "$FILE"; done

Whenever I receive mail it's not identifying the new file.
When I manually create file using root user it's displaying the file name.

What I observed is when I receive mail, the permissions of the file is 600.
When I create the file using root the file permission is 622.

I tried to switch user from root to vmail and run the command but no use.

I am stuck here.

I need to unsubscribe the user whenever I receive new unsubscribe mail immediately.
I setup a Samba server on CENTOS 7 with 10 users and an addtional 2 users 1 called ACCOUNTING and one called HR. Each user has their home directory mapped to their windows machine. Some of the 10 users I added to the group of accounting and some to the HR group. I Chmod the accounting and HR directories to 775. I then created a symbolic link from ACCOUNTING to USER1 but access was denied. What did I miss?
I had this question after viewing linux crontab output.

Hi everyone,
right now I am manually running this script to start a python app. I would like to do this @ reboot.

cd /home/ec2-user/console

python 8090 cloud& <<this runs fine

I tried to create a small bash script ,but cant seem to make it run @ reboot time

cd /home/ec2-user/console
python 8090 cloud&

crontab -e

@reboot sh $HOME/ <<dosnt work

the script runs when executed manually but not @ reboot


I am trying to find a Ghost boot disk for a Linux OS / Fedora

I can use Ubunto Ghost disk the "Try Ubuntu" for any Windows OS's but not having much luck finding an easy solution for Linux.
The Version of Ghost I tried with Linux was 12.04 - it fails to boot, shows a black screen only.
Hey guys, is there good tools to monitor a Linux file server access? As in like change logs and access to files?
Hello Experts,

I have been trying to compile DHCP client for ARM linux platform. I currently use Ubuntu 12.04

../includes/omapip/isclib.h:51:24: error: isc/buffer.h: No such file or directory
../includes/omapip/isclib.h:52:21: error: isc/lex.h: No such file or directory
../includes/omapip/isclib.h:53:21: error: isc/lib.h: No such file or directory
../includes/omapip/isclib.h:54:21: error: isc/app.h: No such file or directory
../includes/omapip/isclib.h:55:21: error: isc/mem.h: No such file or directory
../includes/omapip/isclib.h:56:26: error: isc/parseint.h: No such file or directory
../includes/omapip/isclib.h:57:24: error: isc/socket.h: No such file or directory
../includes/omapip/isclib.h:58:26: error: isc/sockaddr.h: No such file or directory
../includes/omapip/isclib.h:59:22: error: isc/task.h: No such file or directory
../includes/omapip/isclib.h:60:23: error: isc/timer.h: No such file or directory
../includes/omapip/isclib.h:61:22: error: isc/heap.h: No such file or directory
../includes/omapip/isclib.h:62:24: error: isc/random.h: No such file or directory
../includes/omapip/isclib.h:64:24: error: dns/client.h: No such file or directory
../includes/omapip/isclib.h:65:27: error: dns/fixedname.h: No such file or directory
../includes/omapip/isclib.h:66:27: error: dns/keyvalues.h: No such file or directory
../includes/omapip/isclib.h:67:21: error: dns/lib.h: No such file or directory
../includes/omapip/isclib.h:68:22: error: dns/name.h: No such file…
U.S. Department of Agriculture and Acronis Access
U.S. Department of Agriculture and Acronis Access

With the new era of mobile computing, smartphones and tablets, wireless communications and cloud services, the USDA sought to take advantage of a mobilized workforce and the blurring lines between personal and corporate computing resources.

I had this question after viewing redirect certain certain urls to a subdomain on a different server.

I have a particular problem now which, in the meantime I've found a work-around for, but I don't understand why I'm having this problem. I created a series of rewrite matching redirect rules in the htaccess file that points those urls back to our previous server, which now has a subdomain. I have a set of urls that contain query strings that contain spaces (for instance: Kaf, Ali&list=A). When the url gets redirected, the space in the url gets encrypted to %2520 instead of %20 and because of that, the query string is not recognized. I'd like to know why that extra "52" is inserted into the querystring? Here is my redirect rule:
RewriteRule ^artcenter/newsite/en(.*)$$1 [R=301,NC,L]
I should also add that the redirect is to a windows server which might explain this?
Thanks for your help.

Suppose a user's password is NEWYORK555 and the the NTLMv2 hash is captured.

If the attacker plugs it into a password cracker such as john the ripper and uses a wordlist, would it only succeed if the wordlist has NEWYORK555?  Or would John the ripper be smart enough to try NEWYORK with 555?
Hi Guys
II need a little help with text-file transfers
I am using RHEL 7  server on the linux side and win7 or win10 on the windows side
Linux has a FQDN hostname  
preferred methods SSH2 or SFTP  using PUTTY

On my kali Linux running on debian, I need to free up port 80 to use for another service.  
How would I either remove ipv6 because I don't need it, or make it stop listening on port 80

root@kali:~# netstat -an | egrep '80'
tcp6       0      0 :::80                   :::*                    LISTEN
I am setting up a linux server on a small network for people to access their files, each windows computer will have local login.
I will create logins on the linux server that will be for each individual on the network.
I will map each computer with the appropriate folders that belong to those users.
How can I handle it if someone else needs to use someone else's computer and would like to access their personal files?
Should I have 2 logins, one belonging to the user of that system and a guest of some sort but how can they get to their files easily without needing me to map the drive for them? I need simple because these are not very technical people.

This is on a Dell Powervault MD1200 which is serving as storage for an ESXI5.5 host.
There are two 8TB disks for this purpose.
They will act as storage for an RHEL VM server.

Had problems getting it working when setting up as one large VD occupying the entire available space: Link

Thought it was the disks - got new ones: same issue.
Decided to create a VD using only 2TB...success! It works as intended. Seems to be some bug in the Linux or ESXI OS.
I am creating more VDs with the remaining space to make sure this will work.

What I am wondering if this is a good idea? Any potential drawbacks? Is it harder to recover from a disk failure or other such problem?





Articles & Videos



Linux is a UNIX-like open source operating system with hundreds of distinct distributions, including: Fedora, openSUSE, Ubuntu, Debian, Slackware, Gentoo, CentOS, and Arch Linux. Linux is generally associated with web and database servers, but has become popular in many niche industries and applications.