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 have Debian cloud server that I am trying to upgrade to use Java 8.

I am getting these errors but even when I try to upgrade and add the dependencies, further errors occur.

Can anyone let me know what command I can use to install Java 8 and all dependencies?


You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 java-package : Depends: debhelper (>= 9) but it is not going to be installed
                Depends: dpkg-dev but it is not going to be installed
                Depends: fakeroot
                Depends: libasound2
                Recommends: gcc but it is not going to be installed
 libc-bin : Depends: libc6 (< 2.20) but 2.27-2 is to be installed
 locales : Depends: libc-bin (> 2.27) but 2.19-18+deb8u10 is to be installed
           Depends: libc-l10n (> 2.27) but it is not going to be installed
 unifi : Depends: java8-runtime-headless
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

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My Dell Laptop, Intel Core i5 is running Windows 10 Pro 64-bit

Step 1 -  I invoke windows command prompt.  The screen text is White with black background.  That's what I expect.

Step 2  -  I telnet into remote Linux server from my windows computer.  I'm at my home directory.  Screen colors are as expected.

Step 3  -  I invoke Linux command to view contents of my home directory.  The output is displayed in different colors.  Why?  I need colors to remain as expected.

Please see attached.
I have set up UFW on Ubuntu for a mailserver. I have the following rules

To                         Action      From
--                         ------      ----
22/tcp                     ALLOW       Anywhere                  
25/tcp                     ALLOW       Anywhere                  
465/tcp                    ALLOW       Anywhere                  
587/tcp                    ALLOW       Anywhere                  
110/tcp                    ALLOW       Anywhere                  
995/tcp                    ALLOW       Anywhere                  
143/tcp                    ALLOW       Anywhere                  
993/tcp                    ALLOW       Anywhere                  
22/tcp (v6)                ALLOW       Anywhere (v6)             
25/tcp (v6)                ALLOW       Anywhere (v6)             
465/tcp (v6)               ALLOW       Anywhere (v6)             
587/tcp (v6)               ALLOW       Anywhere (v6)             
110/tcp (v6)               ALLOW       Anywhere (v6)             
995/tcp (v6)               ALLOW       Anywhere (v6)             
143/tcp (v6)               ALLOW       Anywhere (v6)             
993/tcp (v6)               ALLOW       Anywhere (v6)  

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However when I run NMAP it is not working. I'm getting the following results for nmap.

Not shown: 990 filtered ports
21/tcp   open   ftp
22/tcp   open   ssh
110/tcp  closed pop3
143/tcp  closed imap
465/tcp  closed smtps
554/tcp  open   rtsp
587/tcp  closed submission
993/tcp  closed imaps
995/tcp  closed pop3s
7070/tcp open   realserver

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Why isn't UFW working?
I'm using CentOS 6.8 but think this is a more general Linux question.

I'm writing a script which modified the hosts file in /etc but have noticed there is another hosts file in /etc/sysconfig/network-scripts/

I've had a search but can't find a description for the use of this host file, does anyone know? I'm trying to work out if I need to change multiple files.

Client has 1 year old Dell Win 10...
There were 2 profiles...Sharon and Norma...
Norma's profile...the current user...had disappeared...does not appear as an option on the login screen...
Sharon's profile is a local profile...she no longer works for the company and they do not know her login password...

I need to be able to boot the computer and create a new profile for Norma...

I have several bootable CD's that I used on Win 7 to reset the admin or any user password on the older OS's...
Both Linux based and Win PE based...None of them work with UEFI on this Dell PC...

If I change to Legacy mode...and change boot order to CD will NOT boot at all...

If I leave it in UEFI mode and try to change the boot order...I do not have an option for CD "first"...only Onboard NIC IPV4 and Onboard NIC IPV6 and disabled...

The default boot is Windows Boot Manager and evidently it cannot identify a CD in the drive and boot from the CD first....

Does anyone have a fix...workaround...boot CD recommendations that will allow the PC to boot from the CD while in UEFI mode...???

Apprecaiste any and all help and suggestions...
HI Experts,
could you hep with this tricky syntax please? I'm trying to execute an aws cli within python3.

Simple aw cli works fine, but could you help me with nested aws cli

This one works fine.
p = Popen(['aws', 'ec2', 'describe-instances', '--instance-ids', instance , '--output', 'table'])

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Pls help with this. Trying to execute in above subprocess syntax. This one describe an aws instance based on user friendly tag name.
aws ec2 describe-instances --instance-ids $(aws ec2 describe-instances --filters  "Name=tag:Name,Values=testjumpbox" --query "Reservations[].Instances[].[InstanceId]" --output text | tr '\n' ' ') --output table

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Hi Team,

I have an requirement on connecting to different linux servers using a shell script.
I have server1 and Server2.

I need to connect to server1 using ssh , check if a file exists if exists then connect to server2 and perform some action say load data.

Is it possible using  a shell script. Any help is really appreciated
I want to teach a course on Udemy. I run Ubuntu on the Dell XPS 13 9360.

For the course I am just going to record my screen with myself talking.

I was hoping you could recommend software and a microphone that would work on Ubuntu.
Hello Experts - I've been trying to start learning how I can use Linux and other open source software to replace more traditional Windows servers and applications.  This would be to both save money and expand my skills.  I've really only handled Windows software in my career and I'd like to change that.  I'm looking for suggestions and ideas that I can check out using free distributions of Linux and open source software.  I thought one area that might be good to start with would be file shares.  Its easy enough for me to spin up a Linux VM but beyond that I don't really know how to get started, especially when it comes to integrating access permissions with AD.  Please send me your suggestions and ideas on how I can start using Linux!
Hi experts,

what is the best way to handle exception in below python3 subprocess scenario please?

I execute below line in my python script.['aws', 'ec2', 'start-instances', '--instance-ids', instance , '--output', 'table'])

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could you suggest a best way to handle exception please? try/except?

Thanks in advance
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Hi  Team,

I need to know how many terminals a user can open in a Linux server. For example as user sam, how many terminals can I open? is there a limit on the no connections to be allowed in Linux server.
I have two servers. On one of these I would like to run Windows Server 2016.

I'm a Linux guy, my computer runs Ubuntu 17.10. I know SSH. What is the Windows equivalent?

I'm running Windows 10 in a VM, should I be dual booting Windows 10 on my computer to access Windows server?
Recently our Storage Array LUN was extended by our Sys Admin group, to allow my DBA team to increase the size of “OCR_VOTE” disk group.  Apparently, this is a new requirement for Oracle Database 12c.  Unfortunately, the Sys Admin group did not format this new extended LUN.

The DBA team has determined we need 50Gig, and this has been confirmed running the Solaris, “format -e” command, and also the “prtvtoc” command.  So, am I totally wrong thinking, my DBA team could just run “format”, select the correct disk, partition, then label, then save?

# format<cr>
Searching for disks ... done

       0. c0t0d0 <SUN146G cyl 14087 alt 2 hd 24 sec 848>
       1. c0t1d0 <SUN146G cyl 14087 alt 2 hd 24 sec 848>
       2. c3t60A98000572D577465346D3936706348d0 <NETAPP-LUN-7330-200.00GB>
is there a way to upgrade to raid1 from a single drive? without wiping and reinstalling os.
adding a drive basically. currently server running only one single drive.
I have a very large WordPress site that's set up on a Linux based shared hosting environment (40+ GB)  .. and I need to find a proper way to migrate it -- in it's entirety -- to a different web hosting provider.  

The problem that I'm having is that I can't seem to download the entire site in one sitting.  Every time I try to download to site to my local machine via FTP (using Filezilla) .. it's not indexing all of the files, and what I end up with is a directory that's only about 15GB in size.

Note that I've also tried creating a full backup archive of the site via the site's hosting cpanel .. but that isn't working at all.  I've tried initiating the backup archive in the early evening, and in the morning, the ZIP file that I'm expecting to find in the site root is no where to be found.  

I'm reluctant to experiment or waste time with any of those WordPress "Backup" or "Duplicator" plugins, as they work pretty much the same way, where they attempt to create giant ZIP file archives, which I'm nearly certain will fail .. and will also hog all of the server's CPU's resources in the process.

I've already contacted technical support about this problem, and they're annoyingly clueless as to why this is happening. It's almost like they're holding the site hostage or something, and this is quickly turning into an emergency situation.  We need to get this site off of the shared hosting environment and set up on a VPS of some kind on another host ASAP.

Why is this …
I am using Windows computer.  I use telnet utility to connect to remote Linux machine and work on that machine remotely.

My embedded 'C' language project is in Linux machine.  I am using vim editor.  

Is it possible to open file in vim editor that is not in the current directory?
For example, from home directory I want to open a 'C' language file that's in any directory in the Linux File System.
how can I suppress this message when ssh into a linux server , i cant seem to find this like no check or something ,

ECDSA key fingerprint is MD5:de:66:6wea:32:dw2:65:d7wwwwwww:1c:a4:05:e0.
Are you sure you want to continue connecting (yes/no)? yes
I've supported SSL certs and configured servers for years, so no newb here.

Had an interesting issue on CentOS 7.  
Let's call my SSL domain, we'll say IP is setup in the virtual host directive (Apache 2.4.6 / OpenSSL 1.0.2k-fips
And the server hosting it linux.domain.local, a CentOS 7.4.1708 box.

Cert is installed, and answering to, everything is good.

Here's where the issue rears it's ugly head -
For some local software, ansible + jenkins, we have to make a host file entry back to the machine's IP itself, so in my etc/host file, I placed:

When I restart apache / openssl, I then get a domain mismatch warning in a browser when visiting the site. If I go to, it gives the mismatch , and when viewing the cert via the browser (view cert), it says the servername is actually linux.domain.local.

If I REM out the /etc/hosts file entry, and restart apache, SSL works as expected.

When the entry is in /etc/hosts, it appears to grab the rDNS name of the machine rather than serving up what I have specified in the <Virtualhost> directive.
To pre-answer, Yes, the directive ServerName is, and the virtual host is setup specifically with the IP:port (

Never seen this on any other Linux / RMP based flavor. One workaround seems to be setting the rDNS, but I don't want to rely on that for our production server(s).
I'd rather know WHY CentOS 7 …
I'm writing a Linux Shell script and would like to have a Boolean variable called FileA_isPresent
I would like to set the variable to true if the file is present and false if not

Is this possible? I've used this in every other language I've used but looking on the net it seems that Linux shell scripts don't handle Boolean variables in the usual way?

Am I wrong? if so it would be great to get some pointers.
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AWS SSM "run " commnand" to pull down a file from s3 bucket and place it into a specific directory

I am attempting to run a shell script that copies  a file ( a pem.key)  from  an S3 bucket , to an AWSes 2 instance

I have the knowlege to get to the run command and run shell scripts no problem , but I have NO IDEA how to copy a file from S3 and place it into the

~/.ssh/ directory ,

the envental goal it to have an applicaion (ansible ) connect to each instance

I think I will first have to copy the PEM key and then that will allow me to copy the key to each instance

how can this be done , I am very new to this part of it

thanks !!
how can I ssh to a linux box and copy the key to the destination in one command

someone showed me this once it is l or ssh-L or somelike that
In a file called ifcfg-eth0 there is a line which states HWADDR=XX:XX:XX:XX:XX

I have a script called "gatherdata" and have set a variable called "HWADDR" and I want the variable to be set to XX:XX:XX:XX:XX

Is there an easy way of doing this? ive had a look on google and have seen the source command but couldn't find a good example to fit my scenario.

Im on CentOS 6.8


I'm attempting to install netbeans 8.2 on a standalone (No internet connect) PC running Fedora 12

I've downloaded and copied over  both the Java "" and ""

I've Followed instructions here

Steps Taken
first opened su terminal and cd to Download folder
chmod +x and

typed install got error about missing destination file operand after

in a file browser double clicked   installation wizard appeared and I accepted the default location


after finished Netbeans open up with only default JAVA apps

attempted to repeat the process with but nothing happens

in a file browser after double   clicking on the file a pop up appears saying this is an executable text file with options to Run, Cancel etc

I chose run but nothing  happens

Any idea how to install the other components?
I need to write html/PHP/ Javasript app and possibly perl but that's a pluggin
OK so I love Linux. Linux is great.

Now I was talking to a consultant about email for a website. He said there's only three types of email: Google, Office 365 and maybe if you know what you're doing Outlook.

Now I am thinking about what he told me and I am thinking about setting up a mail server. Just to put it on my IT cred (I'm a student).

Is it completely 'stupid crap' to run Linux for an email server?

I've avoided running Windows servers to current - is this a good opportunity to run a Windows server?
I am having an issue with sudo on RHEL.

I have a domain account that has been given sudo rights. However I cannot sudo commands (e.g. sudo netstat -ltnup | grep -E ':80') unless its a sudo su - command.

The resulting error is as follows:

Sorry, user [abc] is not allowed to execute '/bin/netstat -ltnup as root on [hostname.domain] 

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Can anyone offer a solution please?






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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