Linux OS Dev

Kernel programming for Linux operating systems can be done with many different languages; C, C++, Python, Perl and Java, which are some of the most common languages used.There are also many different varieties of Linux, such as Ubuntu, Fedora and OpenSUSE.

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How to communicate ipa server with samba domain active directory?
can ipa server install in domin controller?
How add windows as ipa client?
Build an E-Commerce Site with Angular 5
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Build an E-Commerce Site with Angular 5

Learn how to build an E-Commerce site with Angular 5, a JavaScript framework used by developers to build web, desktop, and mobile applications.

i got both braseero and k3b,  but i can't copy an iso of new ubuntu to dvd.  i did it before on older version of ubuntu,but i've forgottten how to do it.  please give a dummies version.  i'm on ubuntu 16 and want 18
is it possible to move samba active directory to freeipa server?

I am trying to update my old VM installation. I updated the kernel to 4.4.0 and ubuntu 16.04 LTS. However, this VM is being used by old programs which I cannot change its code it's out of my control right now.

I am running following command to run my new VM.

Command with new VM: qemu-system-x86_64 -hda <hard-drive> -smp 16 -m 10G -kernel <my-bz-kernel> -append "root=/dev/sda1 console=ttyS0" -enable-kvm

However, in my old VM installation everything was same except, -append part.
Old command: -append "root=/dev/hda console=ttyS0"  

I want to my new ubuntu 16.04 LTS installation can be booted from /dev/hda as well not only /dev/sda1.

I already tried to change /boot/menu.lst file and /etc/fstab but my tries wasn't successfull. Maybe I am doing something wrong

Please help

Thanks a lot

The below one is rough from actual one.  If I call only T2, application works fine. When I call T1 and then T2, then fuse_main fails with /dev/fuse already mounted as per /etc/mtab.

Here, I am surprised, how  T1 thread affects T2 thread. What could be the reason.

void*  someworkerfn()
     //some logic

void* call_fuse_main()
     //prepare agrs (-s,-f,-o,allow_other...)

int main()
      pthread_create(id1, NULL,someworkerfn,NULL);  //joinable thread-T1
      pthread_create(id1, NULL,call_fuse_main,NULL); //joinable thread-T2

      return 0;

I looking for some hosting (international) to locate all my lxd. If you are familiar with that type.
I have a 80 mm thermal USB printer connected to my Ubuntu and it has been automatically detected since I can see its name in the printer list. However, I'm not able to print nothing when I try to print sample text from LibreOffice or Gedit.
This is what I get from dmesg -d:
[  422.674671 <    7,758140>] usb 3-3.1: new full-speed USB device number 7 using xhci_hcd
[  427.971019 <    5,296348>] usb 3-3.1: New USB device found, idVendor=1051, idProduct=1000, bcdDevice= 1.00
[  427.971020 <    0,000001>] usb 3-3.1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[  427.971021 <    0,000001>] usb 3-3.1: Product: NII W2K203DPI USB
[  427.971022 <    0,000001>] usb 3-3.1: Manufacturer: NII
[  427.975340 <    0,004318>] usblp 3-3.1:1.0: usblp0: USB Bidirectional printer dev 7 if 0 alt 0 proto 2 vid 0x1051 pid 0x1000

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The manufacturer (Nippon) provided an old C code sample that should print some text and a photo (for this reason it needs OpenCV 2.4).
I attached the file to this topic with also the SDK document.

I cannot compile it since I get lots of errors related to the OpenCV version, I tried to remove the OpenCV occurrences since I do not need the print the photo, but I get errors:

gcc libNPrint_sample.c /usr/local/lib/ -o test `pkg-config --cflags --libs opencv` -lm -lpthread
libNPrint_sample.c: In function ‘fncTestSample’:
libNPrint_sample.c:75:18: warning: implicit declaration of function ‘cvLoadImage’; did 

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i take a snapshot of my lxd:
i stop lxd (lxd stop "server_name) then i take snapshut (lxc snapshot "server_name" "snap_name")
i check with lxc ls snap was created and i start server (lxc start " servername) i make a ls igen lxc ls snapshot was there.
now i try to restore to snapshut
i  make lxc ls   snapshot for that server missing. the snapshot column is 0 .
is it possible to this snapshot is hide under some place and can restore to that
i have slapd on my ubuntu 18.04 services is running and ok
i try ldapsearch -x get error : Operations error (1)
Additional information: 00002020: Operation unavailable without authentication
and in /var/log/auth.log: ldapsearch: DIGEST-MD5 common mech free
What to adjust, due to the error below?

[smb01@28-218-217-172-on-nets samba]$ cp smb_c.conf /home/share
cp: cannot create regular file ‘/home/share/smb_c.conf’: Permission denied
[smb01@28-218-217-172-on-nets samba]$ 

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OWASP: Forgery and Phishing
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OWASP: Forgery and Phishing

Learn the techniques to avoid forgery and phishing attacks and the types of attacks an application or network may face.

how to connect a backend ldap (fx. slapd)  with a samba (ubuntu) active directory?
Ubuntu 16 server- no GUI available.

I have a small config file called config.xml

I have this folder structure..

Folder A with 100's of subfolders - each subfolder contains a config.xml

I'm looking for a command to find and replace all files called config.xml with my new modified master config.xml file....

thanks for looking
I am using a Plesk server on an Ubuntu 18.04 cloud setup. There are 8 cpu's and 32 GB of ram.

I just did a stress test using

My CPU and Ram didn't seem to go up at all, but about 4 minutes in my sites started timing out.

I have the max php children set to 5 currently. I do not mind increasing that if need be, but I'm not sure what I should do in general to prepare for high traffic use.

I really need to be able to have 200 concurrent users on my server during peak hours.

This test failed with 25. Like I said the ram and cpu weren't even effected so not sure what I need to adjust.
linux (ubuntu) container can not ping from master.
i have a ubuntu 18.04 and i create a lxd. all server is in my dns and domain. i can ping all lxd from other server but in master server is not ping able even i add this host in (/etc/hosts)
ping says : ... Destination Host Unreachable
lxc list show all linux containers in this server with ip.
I am running a Plesk server and am using php-fpm with nginx.

I've looked for a lot of different recommended settings and no matter what I change it seems to still have this issue.

I'm on an Ubuntu 18.04 and I have about 40 websites running with 8cpus and 32 gb of ram on a cloud server.

The biggest suck is the mysql queries. I am looking at moving the databases to RDS as plesk has a plugin to work with that.

The main issue is that I have a lot of php-fpm processes for these sites that are just sleeping and they just suck down more and more ram until it hits 100% usage. I have to go in by hand every few hours and kill the sleeping processes.

I want to have the processes just die when they are not in use.

What is recommended here?
I am using ubuntu and I have an issue where different sites that I host use up a lot of ram with php-fpm and it just gets larger and larger but is sleeping for the most part.

I'd like to run a command every so often that will find the sleeping php-fpm and kill them. Ideally this would be done on those that are using more than a certain percentage or specific usage of ram in some way or have been in the sleep state for a given amount of time.

This way I don't close something that might be needed.

Currently I'm using:

ps axo stat,ppid,pid,comm | grep -w "S" | grep "php-fpm"

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I believe this is a good start to what I want:

kill -9 $(ps axo stat,ppid,pid,comm | grep -w "S" | grep "php-fpm")

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I haven't actually tested this yet as I'm on a production server and can't test till later in the evening.

This code does not take into account how long or how much ram is being used.

Any help would be appreciated.
AD Joined Ubuntu 16.04 server is receiving the following warning upon login of an AD authenticated user.

groups: cannot find name for group ID 50033

We are unable find a way to stop this warning.  We have cleared the SMB cache, removed the cache file, forcing a recache, removed cached_login from pam and still we are unable to eliminate it.  Its more of a an annoyance than anything, but it is causing our users to question it.

Any help would be greatly appreciated.
Good afternoon all,
I have built an Ubuntu Server 18.04.3 LTS VM on an ESXi host. Using the standard install wizard, I partitioned the disks using LVM and encrypted them and supplied a passphrase.
I'm aware that now, when I boot the VM, I will need to supply the passphrase to unlock the encrypted disk and complete the boot process.

The question is this. Is there a command to reboot the VM that I can use and pre-supply the passphrase as a one-off? I understand that this weakens the security model, but I may want to do this for planned maintenance.
Many Thanks
is there voice recognition in ubuntu?

i have used dragon naturally speaking  in windows in the past, but i am trying to not use windows.  if possible.  i like the free of ubuntu.  should i switch to mint?
Exploring ASP.NET Core: Fundamentals
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Exploring ASP.NET Core: Fundamentals

Learn to build web apps and services, IoT apps, and mobile backends by covering the fundamentals of ASP.NET Core and  exploring the core foundations for app libraries.

i have following in my nginx to return 404
location ^~ /wp { return 404; }
how to return 404 for wp and combination like wp-includ, wp-admin, wp...
how to say wp* in expression?
i try to join ubuntu 18.04 to samba domain controller via sssd
i used ubuntu doc.
itry realm discover my domain
realm: No such realm found: my domain.
i do not have any problem for ubuntu16 what is difference between 16.04 and 18.04 (except for netplan ehich is not working at all) in this propose?
I have two laptops one MAc and other running linux ubuntu version 16.04
I wanted to transfer a folder from linux to Mac. I right clicked on the folder and clicked
Local Network Share. The icon of the folder did change. But how do i access it on MAC
Need to bild a SSH Ubuntu account to one and one only Mysql account and no shell access. My idea is to autologin by some script and if that fails then abort. No password from the client. No access to any other ports than 3306. Possible?


I want every user to only have access  by the users unique key.
will alexa work on my ubuntu system?  should i change os to windows?
I would like to know how can I setup  Pxe server (Linux-windows ) so that I can deploy different versions of linux either server or client from single location so to have Ubuntu ,Centos
 Red Hat server edition in one menu   boot LIST  and to be done through Network as pxe  and to  be authorized only to IT stuff ,so the user cannot install it by booting from Network.
please guide me step by step as to have more options and to have clear understanding.

Linux OS Dev

Kernel programming for Linux operating systems can be done with many different languages; C, C++, Python, Perl and Java, which are some of the most common languages used.There are also many different varieties of Linux, such as Ubuntu, Fedora and OpenSUSE.