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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We are planning to implement two factor authentication (2FA)  the solution DUO Security for the on-premise web application for the users who access it from the internet, application we are using is SugarCRM enterprise runs on linux with the following components Apache2, Mysql, PHP7.1, java, elastix.  We are not having centralised management of passwords in windows Active Directory or ldap instead we are using SugarCRM application standard authentication, now to implement the two factor authentication Duo Security Prerequisites is that we deploy a SAML IdP(requires a SAML 2.0 Identity Provider ) and sugarcrm can be configured the accept the SAML, please help me understand on the following
1. what are the steps to be taken like who are the SAML service provider is it something similar like SSL certificate and install in SugarCRM or to setup a internal server and install and configure SAML please explain

2. Duo Security solutionPrerequisites from their website says: Before you deploy the Duo Network Gateway, make sure to complete these requirements.
Deploy a SAML IdP
Duo Network Gateway requires a SAML 2.0 Identity Provider to use as its primary authentication source. You can use the Duo Access Gateway or another provider such as AD FS, OneLogin, or Okta.

Duo Access Gateway secures access to cloud applications with your users’ existing directory credentials (like Microsoft Active Directory or Google Apps accounts) using the Security Assertion Markup …
Cloud Class® Course: Microsoft Office 2010
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Cloud Class® Course: Microsoft Office 2010

This course will introduce you to the interfaces and features of Microsoft Office 2010 Word, Excel, PowerPoint, Outlook, and Access. You will learn about the features that are shared between all products in the Office suite, as well as the new features that are product specific.

Hi everyone. I have an Android 7 device. It's not rooted. I need a file manager/utility that allows me to view the files & folders of the root directory; specifically the System and Data partitions. I don't need 'Write' permissions, just Read-Only. I want to copy some files. In other words, I don't want to root the device. I just need read-only access. I would prefer a file manager type app but I'm open to other methods.

I have tried Solid Explorer. It shows the System Partition but not the Data partition. Thanks.
How to write php output to excel? more than 100 rows and each 10 column. Platform linux.
Does someone know where  the spool file  is stored in a Windows 2012 server when I run a lp command in a Linux server?

I run this command in a linux server
lp -c -d<PRINTER> -w Test.txt

The printer is configured to send the spool to the Windows server. I need to know where is stored the file Test.txt in the windows server

Thank you in advance
This is using a SuSE Linux Enterprise server 11. This is about a mailing software called postfix. This mailing is working fine in production. Please see the (postconf -n) as follows:

alias_maps = hash:/etc/aliases
biff = no
canonical_maps = hash:/etc/postfix/canonical
command_directory = /usr/sbin
config_directory = /etc/postfix
daemon_directory = /usr/lib/postfix
data_directory = /var/lib/postfix
debug_peer_level = 2
debugger_command = PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin ddd $daemon_directory/$process_name $process_id & sleep 5
defer_transports =
delay_warning_time = 1h
disable_dns_lookups = no
disable_mime_output_conversion = no
html_directory = /usr/share/doc/packages/postfix-doc/html
inet_interfaces = localhost
inet_protocols = all
mail_owner = postfix
mail_spool_directory = /var/mail
mailbox_command =
mailbox_size_limit = 0
mailbox_transport =
mailq_path = /usr/bin/mailq
manpage_directory = /usr/share/man
masquerade_classes = envelope_sender, header_sender, header_recipient
masquerade_domains =
masquerade_exceptions = root
message_size_limit = 10240000
message_strip_characters = \0
mydestination = $myhostname, localhost.$mydomain
#myhostname =
mydomain =
mynetworks_style = subnet
newaliases_path = /usr/bin/newaliases
queue_directory = /var/spool/postfix
readme_directory = /usr/share/doc/packages/postfix-doc/README_FILES
relayhost =
relocated_maps = …
I am looking for a SMTP mail relay server preferably in the Linux world with a gui.
Dear Wizards, we are setting a iRedmail Server (Ubuntu v16) and would like to synchronize all mail accounts to an AD server (Window Server 2008R2)

For example: similar to an Exchange Server, when we create a new mail user, it will automatically create an user in AD server

Is there any way to do it? Can you please give me some resources? Many thanks!
I have one access_log under main folder and have to copy that access_log under another folder where external FTP Server can able to download the log automatically.

My Question is Access_log generated in server for Whole day but we need to have only access_log for 15minutes using diff command.

Please let me know the diff command to be used for changing filename automatically everytime once the diff checked between two files.
Hi Experts,

I want to compare directories only on two servers, without files inside each directory.
I was hoping to get output telling me what directories are missing.

Below command works but doesn't tell that parent directory31 is missing on server1.
Is it possible to get just missing directories between two server paths without copying anything?

[sat@server directory]$ rsync -n -av --include='*/' --exclude='*' --delete /home/sat/directory/ sat@server1:/home/sat/directory/
sat@server1 password:
sending incremental file list
sent 385 bytes  received 63 bytes  179.20 bytes/sec
total size is 0  speedup is 0.00 (DRY RUN)
[sat@server directory]$

server output

[sat@server directory]$ pwd
[sat@server directory]$
[sat@server directory]$
[sat@server directory]$ ll
total 16
drwxrwxr-x 3 sat sat 4096 Jul 12 14:32 directory1
drwxrwxr-x 3 sat sat 4096 Jul 12 14:33 directory11
drwxrwxr-x 3 sat sat 4096 Jul 12 14:33 directory21
drwxrwxr-x 3 sat sat 4096 Jul 12 14:37 directory31
[sat@server directory]$

server1 output

[sat@server1 directory]$ pwd
[sat@server1 directory]$
[sat@server1 directory]$ ll

I am trying to pipe data to voipmonitor on a CentOS Linux server. Essentially packets are sniffed on a Windows machine with rpcapd. I have used the following guide to configure this.

I then run the following command on CentOS.

/usr/src/tcpdump-4.0.0/tcpdump -q -s0 -U -n -i rpcap://\\Device\\NPF_{F910A938-3321-4ADD-80B2-9AA43B57B336} -w- | /usr/src/voipmonitor-amd64-22.6.1-static/usr/local/sbin/voipmonitor -r /dev/stdin --config-file=/etc/voipmonitor.conf

I would like to run the above as a service? How can I do that? Or better yet, how can the voipmonitor service just pick up the data retrieved with tcpdump?

I have tried adding the command above to rc.local so its executed at startup but it only works for 10 minutes before something goes wrong.
Cloud Class® Course: CompTIA Cloud+
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Cloud Class® Course: CompTIA Cloud+

The CompTIA Cloud+ Basic training course will teach you about cloud concepts and models, data storage, networking, and network infrastructure.

I'm configuring postifx mail server in centos 7. i have facing problem related rate limit outgoing mails. my requirement is 3 mail every 1m. so what type of configuration in and i hope you will help me.

Thank you
Hello i'm configuring the Owncloud X Appliance and have some questions that i can't find answer

1- It’s now accesible from the web by here
but user can still access this page
Is there a way to deny access to this page https://owncloud.domain/univention/portal/#category=software and just have access to https://owncloud.domain/ownCloud

2- How can i change owncloud url to : https://owncloud.domain/ instead of https://owncloud.domain/ownCloud
i found this link but it don't seem to be relate to the appliance

3- If i want to increase space on the appliance once ive add more space on my lun what other step i need to do

Thanks for helping me !
i'm running ubuntu 16.04 ( xenial ) with 4.4.0-128-generic kernel

i create a bind mount using the following commands

root@sqlbol115:/usr/local/gitclones-hbs/User# mkdir /tmp/testmountsrc
root@sqlbol115:/usr/local/gitclones-hbs/User# touch  /tmp/testmountsrc/a

root@sqlbol115:/usr/local/gitclones-hbs/User# mkdir  /tmp/testmountdst
root@sqlbol115:/usr/local/gitclones-hbs/User# mount --bind -o ro /tmp/testmountsrc/ /tmp/testmountdst/

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the mount does work as expected :
root@sqlbol115:/usr/local/gitclones-hbs/User# ls /tmp/testmountdst/

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but the mount command reports something clearly wrong
root@sqlbol115:/usr/local/gitclones-hbs/User# mount | grep testmount
/dev/sda5 on /tmp/testmountdst type ext4 (ro,relatime,data=ordered)

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/dev/sda5 is actually the mount point for /tmp and the flags have been copied.
i tested with a real world scenario while creating a chroot environment and this seems to be consistent behavior

is that a feature or a bug ?
any way i can prevent this obviously idiotic behavior ?

i recollect this is not my first time seing this on linux boxes ... this makes scripting unsafe in so many ways :(

thanks a bunch
I have devices that pull their IP addresses from DHCP which are not on the domain. I however need the devices to provide he DHCP server with a hostname -- make a DNS entries and update it when the IP changes.

Is this possible to do when the infrastructure is as the following:

ISC DHCP ( dhcpd )
Microsoft DNS ( AD DNS )

how to fix "GPT PMBR size mismatch in Gentoo" after clone.
I just clone my old hard disk (100G) to the new bigger hard disk(300G).
I can use my new system without any issue, but the space only have 100G, not 300G.
I type "fdisk -l", it said  "GPT PMBR size mismatch (209715199 != 629145599) will be corrected by w(rite) "
I would like use the whole  300G.

I do some research, it looks "parted" can fix it, but I do not know how and the risk.

Anyone can tell me how to do it.


Device       Start       End   Sectors  Size Type
/dev/sda1     2048      6143      4096    2M BIOS boot
/dev/sda2     6144    268287    262144  128M EFI System
/dev/sda3   268288   1316863   1048576  512M Linux filesystem
/dev/sda4  1316864 209713151 208396288 99.4G Linux filesystem
While trying to install Zabbix on a new install of CentOS 7 I keep running into the same errors surrounding installing MySQL.

Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base:
 * extras:
 * updates:
Resolving Dependencies
--> Running transaction check
---> Package mariadb-server.x86_64 1:5.5.56-2.el7 will be obsoleted
--> Processing Dependency: mariadb-server for package: akonadi-mysql-1.9.2-4.el7.x86_64
---> Package mysql-community-server.x86_64 0:5.6.40-2.el7 will be obsoleting
--> Processing Dependency: mysql-community-common(x86-64) = 5.6.40-2.el7 for package: mysql-community-server-5.6.40-2.el7.x86_64
--> Processing Dependency: mysql-community-client(x86-64) >= 5.6.10 for package: mysql-community-server-5.6.40-2.el7.x86_64
--> Running transaction check
---> Package mariadb.x86_64 1:5.5.56-2.el7 will be obsoleted
---> Package mariadb-server.x86_64 1:5.5.56-2.el7 will be obsoleted
--> Processing Dependency: mariadb-server for package: akonadi-mysql-1.9.2-4.el7.x86_64
---> Package mysql-community-client.x86_64 0:5.6.40-2.el7 will be obsoleting
--> Processing Dependency: mysql-community-libs(x86-64) >= 5.6.10 for package: mysql-community-client-5.6.40-2.el7.x86_64
---> Package mysql-community-common.x86_64 0:5.6.40-2.el7 will be installed
--> Running transaction check
---> Package mariadb-libs.x86_64 1:5.5.56-2.el7 will be obsoleted
---> …
I'm looking for a good tutorial / guide how to install imagemagick with libsvg (rsvp) support and Iamgick on a Debian System,

I found much on the internet but really ALL failed in case of wrong versions or finally without libsvg support.

Background: I use XAMPP V on a Mac that has installed a Linux (Debian) OS.
I am in the process of standing up a Ubuntu Linux server from a .vhd file.
The existing partitions are too small to handle the backup file thus I need to add extra partition space to the system.
This is a hyper-V hosted system.
I've never done this before. Can someone give me some guidance on what I will need to do?
Initially I was building a new server with 2 Tb of disk space but we decided to use a existing secured version of a .ova file which I converted over to a .vhd file.
Can anyone help me understand what I need to do?
We have more space available, the vhd was set to more than what the original image was configured for.
How can I expand the relevant partitions to take account of this extra available space?
Which partitions should get the extra space?  Opt is where the backups are stored via the main application so that one definitely needs to be expanded.
Filesystem                        Size  Used Avail Use% Mounted on
udev                               16G     0   16G   0% /dev
tmpfs                             3.1G  8.7M  3.1G   1% /run
/dev/mapper/vg00-root              19G  1.4G   17G   8% /
tmpfs                              16G  4.0K   16G   1% /dev/shm
tmpfs                             5.0M     0  5.0M   0% /run/lock
tmpfs                              16G     0   16G   0% /sys/fs/cgroup
/dev/sda1                         464M   58M  382M  14% /boot
/dev/mapper/vg00-opt               76G   76G     0 100% /opt
tmpfs                            …
This is using SuSE Linux enterprise server 11 with SP3. There are few user accounts created. These users were used for application with ftp file transfer. Recently, found that the file and folder permissions were changed. If I remember correctly, the default umask should be 022, so as, the file created should be 644, and folder 755. However, files created by this user is more restricted with 600. I suspect the umask was changed was this user. btw, where to check and troubleshoot the problem?

Cloud Class® Course: MCSA MCSE Windows Server 2012
LVL 12
Cloud Class® Course: MCSA MCSE Windows Server 2012

This course teaches how to install and configure Windows Server 2012 R2.  It is the first step on your path to becoming a Microsoft Certified Solutions Expert (MCSE).

what is the meaning of below command

less log123.log | grep -i nullpointerexception

why we use less and then grep on it

Please advise
in vi we can use /nullpointerexception to find that string right.

how to find how many occurrence of that string total and go to say 10th occurence line
please advise
when i open with winscp that opens old stale file compared to putty opening of same file say xyz.ccfg

i wonder why winscp does not show recent changs?

please advise
tail -f logfile.log

what is the meaning of above command.

i see logs rolling too fast.

is there is a way i can slow it down to see clearly slowly

any god tips, links, resources on how to debug production logs efficiently just using putty without any fancy costly tools?

please advise
I have 8GB RAM memory on a Mac.  How can I tell if upgrading to 16GB RAM would help? In terms of, for example, how often does an appl need more than 8GB and start disk-swapping, slowing me down a bit? What type of applications are happier with 16GB RAM?
(I have 3 Macs, one with 4GM RAM, 1 with 8GB RAM, and one with 16GB RAM. When I look at Activity Monitor, they all seem to use less than what is installed of course)
Hi Experts,
According to my work , iI have a java code which generate shell script for ftp files.
So in the code
ftp.append("cd /home/user/user output/files for June ");

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But according to shell script , If folder name contains space, then either we need to keep complete path inside quotes or space we can replace with back slash
for eg
cd "/home/user/user output/files for June " 
cd /home/user/user\output/files\for\June

But in java , It is not allowing me to put both  back slash \ and " saying invalid escape sequence.
How can I resolve it?
Thanks in Advance Experts............






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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