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 running nginx on a raspberry pi.

I want to run it as a reverse proxy.

I have multiple servers running ssl and one needing forwarding on multiple ports (2195,2196,5228,5229,5230,38880,38881,80,443)

My question is two fold.

Is this even possible? in other words can you forward ports that are non http based ports. For example ports other than 80 8080 443 stuff like that.

I own a domain linked to a dynamic DNS service so I have * available (* being anything I want it to be)
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I am setting an Ubuntu Mate release for armhf hardware and till now I managed quite well to get almost everything working (Firefox, Evolution Mail, Pidgin, Chromium with NTLM, Printers, Proxy,…)

I am able to get the machine into AD without any issues

I am also able to access with Samba folders in our active directory \\server1\%user% using ntlm authentication.

My main issue is to mount automatically home directory (\\server1\%user%) for domain users on the Ubuntu machine in /home/%(DOMAIN_USER) or other location such as /media or /mnt.

I installed libpam_mount along with cifs-utils but I am not managing to mount the home directory on from  \\server1\ by using libpam_mount module and exiting the xml file.

Just that you know, Kerberos authentication works, as when I run klist I get the Kerberos ticket info.

Any help would be appreciated. If you need more details, please don't hesitate to ask.
Hello:  I am new to Linux and don't have a Linux system to work on.  I have a database background (user, planner, DBA, etc.) but no hand-on Linux experience or training in Linux administration.

I am working with a customer who regularly lets their OS-level passwords on their Linux servers expire.  They don't log in very often, so when they do, they find that the password has expired and they can't remember the old password to reset it.  

They then have to engage my company's customer service staff, who are getting a bit vexed by having to do custom work for which they previously didn't charge any money.  (For this frequent offender, they are changing that policy.)  

This also happens when our customer service staff is preparing to do service work at the Linux level and ask the customer for the password, only to find that the customer hasn't a clue.

My question is:  Will the solution given in this string of postings work for the OS level password, or only for user passwords?

If not, is there a similar solution that will?

Thank you for any assistance you might be able to give me on this question.
I am just wondering what this change in July 2018 is in the world wide web.  Are sites insistent on being on secure servers, using HSTS and OCSP stapleing?
heard there was a change coming in effect in June or Junly this year but I can't find any information on it.  Is it strictly based on SEO techniqures, for example?

Thanks for your help
We have tried to configure Postfix for multiple domains with dedicated IPS for each domain.
When I am sending mail from a different domain then header shows same local or main domain name. For all domains:

Received: from localhost (localhost [])
      by (Postfix) with ESMTP id 6DF1A2048CEB
      for <>; Sun, 18 Mar 2018 10:56:36 +0530

And I would like to change above header like this

for domain1:
Received: by id hlnq360001gt for <>; Sun, 18 Mar 2018 10:09:26 +0530

for domain2:
Received: by id hlnq360001gt for <>; Sun, 18 Mar 2018 10:09:26 +0530

We used this regex in smtp header checks:

/^Received:[[:space:]]from[[:space:]]localhost+(.*)\n+(.*)by+(.*)\n+(.*)/ REPLACE Received: by$3$4

Received: by (Postfix) with ESMTP id 682662048CEB      for <>; Sun, 18 Mar 2018 12:00:12 +0530

here we are not able to replace the with the sending domain.
Need to ensure directory permissions stay set to 755. We have a program that stores files in /var/log/rederUI. I need the permissions to stay set on this directory to 755 so that internal service accounts can access world readable files in it. Vendor patches will change the permissions to be more restrictive so each time the server is updated, I have to reset permissions. I'd like to create a cron job to reset them to 755 anytime the restart is done. Though I know how to do this manually, what would be the best way to set it up in cron? Create a simple bash script to set the permissions and have cron run it? Is there a way to have cron only run a script or command at startup?
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?
winscp how to name the link i save to favorite

say i have link

i want to save above link with name as production_logs_folder

I have other link as below


i want to save above link with name as crm_logs_folder

how do i name like above so that it is easy to locate and navigate later
\please advise
Server: HP ProLiant DL360e Generation 8
RAID Controller: Dynamic Smart Array B320i RAID Controller
RAID Configuration: RAID-1 (2x1TB drives)

Ubuntu 16.04 <or> Ubuntu 14.04

Hi All,
I am trying to install Ubuntu Server on the HP ProLiant, but even thought I set up the RAID configuration during the Pre-boot, the Ubuntu setup does not show that any drives are detected.  *See attached screenshot*.
I will also note that I am NOT a Linux guy.  But in the Windows world, if you can't see the drives it's because the driver for the RAID controller is missing.  The fix is getting the driver from the manufacturer website, put it on a USB, and boom.  But I'm having difficulty trying to determine if that's the exact issue and how to obtain the right drivers for Linux.  Am I even on the right track?

Any help would be greatly appreciated!

I'm writing an installation shell script and part of the installation procedure is to setup a few desktop panel launchers for the users.

Is this possible to script?

The manual steps I currently do are ..
Right Click Panel -> Add to Panel -> Create Application Launcher ->
Type : Application In Terminal
Name: Application1
Command: /Path/Application1

I usually then click on the icon and set a specific icon.

I can find plenty of examples for manual steps but nothing via the command line
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How to block outgoing SMTP-connections from one IP on a Linux server.

I have a Linux server (Running Plesk) with 2 IP's
IP1 is used for website
IP2 is used for mail

I want to block users from creating script to send mail directly (spam).
All mail are supposed to be send via the mailserver on IP2

In the Plesk Firewall, I can block incoming connections on ex. port 25, but not (as far as I can see) outgoing.

I found this suggestion:
iptables -I OUTPUT -m owner ! --uid-owner postfix -m tcp -p tcp --dport 25 -j REJECT

How can this be done?

I have had to disable SELinux to get an application installed ,I was wondering if anyone has ever used 'AUDIT2ALLOW' to re-tag the objects in SELINUX and re-enable SELINUX  

I have never ever worked with SELINUX before and could use any advice you can give

So if I manually connect using sftp from a centos box to my Proftpd server and issue a get command to grab a file, all's good.

If I do it in a script, it fails after getting the file  (next step would be to delete the file which it never does)

It's driving me round the bend abit, so any help would be greatly appreciated.

on the sftp client side
Log from Scripted version
2018-03-15 12:34:35,029 [30711] <sftp:6>: received READ (5) SFTP request (request ID 11, channel ID 0)
2018-03-15 12:34:35,030 [30711] <sftp:7>: received request: READ 8fc9867310df242f 0 32768
2018-03-15 12:34:35,030 [30711] <sftp:8>: sending response: STATUS 1 'End of file' ('End of file' [-1])
2018-03-15 12:34:35,030 [30711] <ssh2:9>: sending CHANNEL_DATA (remote channel ID 0, 37 data bytes)
2018-03-15 12:34:35,030 [30711] <ssh2:19>: waiting for max of 600 secs while polling socket 1 using select(2)
2018-03-15 12:34:35,030 [30711] <ssh2:3>: sent SSH_MSG_CHANNEL_DATA (94) packet (80 bytes)
2018-03-15 12:34:35,031 [30711] <ssh2:11>: channel ID 0 remote window size currently at 2096633 bytes
2018-03-15 12:34:35,031 [30711] <ssh2:19>: waiting for max of 600 secs while polling socket 0 using select(2)
2018-03-15 12:34:35,031 [30711] <ssh2:20>: SSH2 packet len = 44 bytes
2018-03-15 12:34:35,031 [30711] <ssh2:20>: SSH2 packet padding len = 5 bytes
2018-03-15 12:34:35,031 [30711] <ssh2:20>: SSH2 packet payload len = 38 bytes
2018-03-15 12:34:35,031 [30711] <ssh2:19>: waiting for max of …

In a modern Oracle 12.x RAC database and all things being equal, would it be advisable to explicitly create an ACFS file system for storing shared files or would ASM be more appropriate (like Wallet files etc.)?

  • You do not want to store the files locally on each node if possible.
  • You do not already have an ACFS file system but do have ASM (because you have a RAC).

I am basically looking for the current best practice in storing shared files as seen in the industry.  What has the best ROI etc.


we are running windows 7 and windows 10 as our samba clients.  samba is setup in Linux server.

windows 7 users are able to access the samba share but not windows 10 users.

we are using SMB v1
I have a setup with RHEL 7.4 machines that connect to Active Directory running on a Windows Server 2016 Datacenter edition. The Linux machines are in direct integration with the AD.

Since IDMU is removed from this version of Windows, the solution is to use sssd to autogenerate UID and GID numbers. I am not able to understand how the autogenerated GID will be mapped to the actual group on the Linux machine.

For ex, if user john is a member of LinuxGroup in the AD and is logged in and that should be mapped to group localgrp on the Linux machine, how will this work out? How would he get linuxgrp privileges if the autogenerated GID is 500 but localgrp GID is 10 on the Linux machine?

To have only central management of users, we are not allowed to add users directly in Linux i.e. in /etc/passwd

Is there way to execute shell script on Linux Box from Windows Power shell script?
Striggling with dhcp on linux.  
Need to know scope range, reservations, lease hours/days, % scope used, etc.

Here is what I have:   can can you take  apeek and help with commands?

# File managed by Chef

# set this to store vendor strings.
set vendor-string = option vendor-class-identifier;

allow booting;
allow bootp;
allow unknown-clients;
allow client-updates;

authoritative ;
ddns-domainname "";
ddns-update-style interim;
ddns-updates on;
default-lease-time 6400;
filename "pxelinux.0";
max-lease-time 86400;
next-server 10.x.x.x;
one-lease-per-client true;
ping-check true;
update-static-leases true;

option domain-name "";
option domain-name-servers 10.x.x.x,;
option domain-search "", "", "someothername";
option host-name  = binary-to-ascii (16, 8, "-", substring (hardware, 1, 6));

zone {
 primary 10.x.x.x;
 # uses name format could use IP address format
# zone {
#  primary serverhostname;
# }

include "/etc/dhcp/groups.d/list.conf";
include "/etc/dhcp/subnets.d/list.conf";
include "/etc/dhcp/hosts.d/list.conf";
~     …
what is curl and ping in unix.

lets say i have service called

now if do
get the exact_name of service from above result
then use that exact name to ping
ping exact_name
then we can get ip of the service where it is running?

please advise
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Need to migrate DHCP from old BIND box to Windows DC Server 2016.  Anyone can point to the right direction and steps required?
Also, lots of users are on Ubuntu and Macs.  Do they require an additional DHCP client to communicate with Windows DHCP Server or should be good by default?
Thanks in advance!!
verbose info neededhow can I get more verbose information with cloud formation templates in AWS ?

for example below , how can I get more information on the circled item , how can I see a verbose log on this ?\

After using apache and weblogic for more than 10 years(the last working module used is: mod_wl_22), I am ready to set up a replacement system with the newer version of the connector module (mod_wl_24) for our production.

I follow the official documentation from this link:

The server OS is:
root@server90 ~]# uname -a
Linux server90 4.1.12-94.3.9.el7uek.x86_64 #2 SMP Fri Jul 14 20:09:40 PDT 2017 x86_64 x86_64 x86_64 GNU/Linux

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Apache version:
[root@server90 ~]# apachectl -version
Server version: Apache/2.4.6 ()
Server built:   Oct 19 2017 14:54:33

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APACHE_HOME folder details
[root@server90 httpd]# pwd
[root@server90 httpd]# ll
total 8
drwxr-xr-x 2 root root   58 Mar 10 21:58 conf
drwxr-xr-x 2 root root  103 Mar 10 21:56 conf.d
drwxr-xr-x 2 root root 4096 Mar 10 21:42 conf.modules.d
drwxr-xr-x 2 root root 4096 Mar 11 15:31 lib
lrwxrwxrwx 1 root root   19 Feb 22 16:32 logs -> ../../var/log/httpd
lrwxrwxrwx 1 root root   29 Feb 22 16:32 modules -> ../../usr/lib64/httpd/modules
lrwxrwxrwx 1 root root   10 Feb 22 16:32 run -> /run/httpd
[root@server90 httpd]# 

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I created a lib folder at the APACHE_HOME folder and copy all the lib files and this connection module(downloaded from Apache foundation website) into this folder
[root@server90 httpd]# cd lib/
[root@server90 lib]# ll
total 138808
-rwxr-xr-x 1 root root  6990875 Mar 10 21:00
-rwxr-xr-x 1 root root  6990875 Mar 10 21:00
-rwxr-xr-x 1 root root 58793741 Mar 10 21:00
-rwxr-xr-x 1 root root 58793741 Mar 10 21:00
-rwxr-xr-x 1 root root   409107 Mar 10 21:00
-rwxr-xr-x 1 root root  1768370 Mar 10 21:00
-rwxr-xr-x 1 root root   544150 Mar 10 21:00
-rwxr-xr-x 1 root root  6747034 Mar 10 21:00
-rwxr-xr-x 1 root root   346242 Mar 10 21:00
-rwxr-xr-x 1 root root    98521 Mar 10 21:00
-rwxr-xr-x 1 root root    72281 Mar 10 21:00
-rwxr-xr-x 1 root root   567319 Mar 11 15:24
[root@server90 lib]# 

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After that, I added directive for loading the module  into the $APACHE_HOME/conf/httpd.conf file:
[root@server90 httpd]# cd conf
[root@server90 conf]# ll
total 36
-rw-r--r-- 1 root root 11814 Mar 11 00:49 httpd.conf
-rw-r--r-- 1 root root 13077 Oct 19 17:55 magic
-rw-r--r-- 1 root root  4104 Mar 10 21:58 weblogic.conf
[root@server90 conf]# cat httpd.conf 
LoadModule weblogic_module /etc/httpd/lib/

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Then verify if this apache web server has included the dynamic sharing module: mod_so.c
[root@server90 conf]# apachectl -l
Compiled in modules:
[root@server90 conf]# 

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the next step is to try to test the syntax of httpd.conf:
[root@server90 conf]# apachectl -t
httpd: Syntax error on line 355 of /etc/httpd/conf/httpd.conf: Cannot load modules/ into server: cannot open shared object file: No such file or directory
[root@server90 conf]# 

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it shows some error message:

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Dear Experts, is there any way to monitor the Hardware's status (status of array, of disk, temporature, ....) of a IBM or HP servers?

We are using Zabbix 3.4. Many thanks!
Hi Experts,

How to connect to postgres, elastic search server in linux, ubuntu on AWS to  with Dango-cms or Wagtail cms from dev machine on windows

Please tell me how elastic search details are stored in database and how to connect to do a elastic search which is in postgres database.

All indexes of elastic search is stored in postgres sql.  How will i connect to postgres from windows dev machine.

And How can I access the postgres database in ubuntu aws to development machine have django-cms or wagtail cms on windows.


database connection string is created with dj_database_url  the connection string is DATABASE=postgres://user:password@server/database.

Please help me,

I get the following error when I build the wagatail cms - based on python
python makemigrations

throws the below error.

django.db.utils.OperationalError: could not connect to server: Connection timed out (0x0000274C/10060)
        Is the server running on host "" and accepting
        TCP/IP connections on port 5432?

I connect string sample postgres sample is postgres://test1:test2@

When I go inside the aws machine through putty (ssh) 54.*.*.*:22


telnet 5432

It is connection is success full.

but not able to connect from outside aws machine from a windows pc (development machine).

With Many Thanks,
Bharath AK
how can I place a key in a AWS RHEL instacne with "user data"

is it possible to create a "here" script and have it execute on AWS instance "user data"?

like this

user data with a bash script in it#!/usr/bin/env bash
mkdir -p /home/ec2-user/.ssh
cat <<EOF >  /home/ec2-user/.ssh/docker-master-key.pem

I want to be able to pass a key to an instance upon boot, I have used just this above and it does not seem to do anything at all , I can not find any errors , how can I find out logging from this user data ?







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.

Vendor Experts

Sandeep KumarKernel Data Recovery Learn more about Kernel Data Recovery
Naveen SharmaKernel Data Recovery Learn more about Kernel Data Recovery