Category Archives: how-to

Problem connecting to KVM with Virt-Manager

Recently I have had some issues with connecting from my laptop running Linux OS (Fedora 30, Xubuntu 19.04) from virt-manager to server running KVM. Virt-Manager keeps asking me for root password, which was very annoying.

The solution was simple – first I had to create ssh keys which then I needed to send to my CentOS(7) server running KVM

# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/username/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /home/username/.ssh/id_rsa.
Your public key has been saved in /home/username/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567 username@laptop
The key's randomart image is:
+---[RSA 2048]----+
|     xxxxxxxxxxxx|
|      xxxxxxxxxx |
|     x x x x x x |
|    xxxxxxxxxx   |
|     x x x x x   |
|  xx  xx   xx x  |
|   x x x x x x   |
|   xxx x x x x   |
|    xxxxxxxxxxxx |
+----[SHA256]-----+
# ssh-copy-id root@192.168.200.50
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@192.168.200.50's password:

Number of key(s) added: 1

Now try logging into the machine, with:   "ssh 'root@192.168.200.50'"
and check to make sure that only the key(s) you wanted were added.

# ssh-keygen

Generating public/private rsa key pair.

Enter file in which to save the key (/home/username/.ssh/id_rsa):

Enter passphrase (empty for no passphrase):

Enter same passphrase again:

Your identification has been saved in /home/username/.ssh/id_rsa.

Your public key has been saved in /home/username/.ssh/id_rsa.pub.

The key fingerprint is:

SHA256:1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567 username@laptop

The key's randomart image is:

+---[RSA 2048]----+

| xxxxxxxxxxxx|

| xxxxxxxxxx |

| x x x x x x |

| xxxxxxxxxx |

| x x x x x |

| xx xx xx x |

| x x x x x x |

| xxx x x x x |

| xxxxxxxxxxxx |

+----[SHA256]-----+

# ssh-copy-id root@192.168.200.50

/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed

/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys

root@192.168.200.50's password:

Number of key(s) added: 1

Now try logging into the machine, with: "ssh 'root@192.168.200.50'"

and check to make sure that only the key(s) you wanted were added.

After that I was able to use Virt-Manager without any asking for password.

How-to install cockpit on CentOS 7

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Here is a quick install guide how I setup Cockpit on my CentOS 7 servers:

First update CentOS 7 server

Updating server
Shell

yum update

1

yum update
Install cockpit

Installing cockpit
Shell

yum install cockpit cockpit-machines cockpit-packagekit cockpit-dashboard cockpit-system cockpit-storaged -y

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yum install cockpit cockpit-machines cockpit-packagekit cockpit-dashboard cockpit-system cockpit-storaged -y
Change firewall settings

Cockpit firewall setup
Shell

systemctl enable --now cockpit.socket firewall-cmd --permanent --zone=public --add-service=cockpit firewall-cmd --reload

1
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systemctl enable --now cockpit.socket
firewall-cmd --permanent --zone=public --add-service=cockpit
firewall-cmd --reload
Access CentOS 7 server via Cockpit webpage

Accessing cockpit
Shell

http://your_server_ip:9090

1

http://your_server_ip:9090

And that’s all 😉

How to install MS SQL Server 2017 on CentOS 7

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There are many instructions and how-to’s regarding installing MS SQL Server 2017 on CentOS 7 but here are my notes about it:

You should plan how to setup your CentOS 7 system because by default MS SQL Server hold his files in those directories:
1. SQL Server 2017 file location after install
  
  MS SQL Server 2017 program file location
  Shell
  
  /opt/mssql
  
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  /opt/mssql
2. database and others
  
  MS SQL Server 2017 database and logs location
  Shell
  
  /var/opt/mssql/.system /var/opt/mssql/data /var/opt/mssql/log /var/opt/mssql/secrets
  
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  2
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  4
  
  /var/opt/mssql/.system
  /var/opt/mssql/data
  /var/opt/mssql/log
  /var/opt/mssql/secrets
3. Of course this directories can be changed after install, but does anyone change directories for MySQL/PostgreSQL ?
Read carefully documentation provided by Microsoft ®, especially this:
https://docs.microsoft.com/en-us/sql/linux/quickstart-install-connect-red-hat?view=sql-server-2017
https://docs.microsoft.com/en-us/sql/linux/sql-server-linux-performance-best-practices?view=sql-server-2017
https://docs.microsoft.com/en-us/sql/linux/sql-server-linux-configure-mssql-conf?view=sql-server-2017
Check if your software will work with MS SQL Server running on Linux. Some software will work but you will probably have no support if you run it that way.

Here is how I have setup my CentOS 7 to work with MS SQL Server only

I have created Virtual Machine which has:
2 x CPU’s
8 GB of RAM
100 GB of space
1 x NIC
Disk partitioning:
/boot – 1024 MB
/ – 30 GB
/var – 60 GB
/tmp – 5 GB
/var/log – 5 GB
/swap – 8192 MB

CentOS 7 setup

Update system

Shell

yum update

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yum update
Enable EPEL repo (not necessery, but I like to have it)

Shell

yum install -y epel-release

1

yum install -y epel-release
Download MS SQL Server 2017 repo

Shell

curl -o /etc/yum.repos.d/mssql-server.repo https://packages.microsoft.com/config/rhel/7/mssql-server-2017.repo

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curl -o /etc/yum.repos.d/mssql-server.repo https://packages.microsoft.com/config/rhel/7/mssql-server-2017.repo
Install

Shell

yum install -y mssql-server

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yum install -y mssql-server

Setup

[root@echo ~]# /opt/mssql/bin/mssql-conf setup
Locale pl_PL not supported. Using en_US.
Choose an edition of SQL Server:
  1) Evaluation (free, no production use rights, 180-day limit)
  2) Developer (free, no production use rights)
  3) Express (free)
  4) Web (PAID)
  5) Standard (PAID)
  6) Enterprise (PAID)
  7) Enterprise Core (PAID)
  8) I bought a license through a retail sales channel and have a product key to enter.

Details about editions can be found at
https://go.microsoft.com/fwlink/?LinkId=852748

Use of PAID editions of this software requires separate licensing through a
Microsoft Volume Licensing program.
By choosing a PAID edition, you are verifying that you have the appropriate
number of licenses in place to install and run this software.

Enter your edition(1-8): 3
The license terms for this product can be found in
/usr/share/doc/mssql-server or downloaded from:
https://go.microsoft.com/fwlink/?LinkId=855862

The privacy statement can be viewed at:
https://go.microsoft.com/fwlink/?LinkId=853010

Do you accept the license terms? [Yes/No]:Yes

Choose the language for SQL Server:
(1) English
(2) Deutsch
(3) Español
(4) Français
(5) Italiano
(6) 日本語
(7) 한국어
(8) Português
(9) Русский
(10) 中文 – 简体
(11) 中文 （繁体）
Enter Option 1-11: 1
Enter the SQL Server system administrator password: 
Confirm the SQL Server system administrator password: 
Configuring SQL Server...

The licensing PID was successfully processed. The new edition is [Express Edition].
ForceFlush is enabled for this instance. 
ForceFlush feature is enabled for log durability.
Created symlink from /etc/systemd/system/multi-user.target.wants/mssql-server.service to /usr/lib/systemd/system/mssql-server.service.
Setup has completed successfully. SQL Server is now starting.
[root@echo ~]#

[root@echo ~]# /opt/mssql/bin/mssql-conf setup

Locale pl_PL not supported. Using en_US.

Choose an edition of SQL Server:

1) Evaluation (free, no production use rights, 180-day limit)

2) Developer (free, no production use rights)

3) Express (free)

4) Web (PAID)

5) Standard (PAID)

6) Enterprise (PAID)

7) Enterprise Core (PAID)

8) I bought a license through a retail sales channel and have a product key to enter.

Details about editions can be found at

https://go.microsoft.com/fwlink/?LinkId=852748

Use of PAID editions of this software requires separate licensing through a

Microsoft Volume Licensing program.

By choosing a PAID edition, you are verifying that you have the appropriate

number of licenses in place to install and run this software.

Enter your edition(1-8): 3

The license terms for this product can be found in

/usr/share/doc/mssql-server or downloaded from:

https://go.microsoft.com/fwlink/?LinkId=855862

The privacy statement can be viewed at:

https://go.microsoft.com/fwlink/?LinkId=853010

Do you accept the license terms? [Yes/No]:Yes

Choose the language for SQL Server:

(1) English

(2) Deutsch

(3) Español

(4) Français

(5) Italiano

(6) 日本語

(7) 한국어

(8) Português

(9) Русский

(10) 中文 – 简体

(11) 中文（繁体）

Enter Option 1-11: 1

Enter the SQL Server system administrator password:

Confirm the SQL Server system administrator password:

Configuring SQL Server...

The licensing PID was successfully processed. The new edition is [Express Edition].

ForceFlush is enabled for this instance.

ForceFlush feature is enabled for log durability.

Created symlink from /etc/systemd/system/multi-user.target.wants/mssql-server.service to /usr/lib/systemd/system/mssql-server.service.

Setup has completed successfully. SQL Server is now starting.

[root@echo ~]#

Enabling TCP port on firewall

Enabling TCP port for MS SQL
Shell

firewall-cmd --zone=public --add-port=1433/tcp --permanent firewall-cmd --reload

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firewall-cmd --zone=public --add-port=1433/tcp --permanent
firewall-cmd --reload
Connecting from SQL Management Studio
1. Logon screen
2. After logon screen

I think this is all … for now 😉 I will try to write something more after I will test it in production.

Prestashop 1.6.x.x contact form problem with sending messages.

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Hi,

Yesterday my client told that his Prestashop 1.6.x.x don’t send messages from the contact form. Here is what i have done to solve this:

Edit your Prestashop contact-form.tpl which is located in

Prestashop contact form location
Shell

/themes/YOUR_THEME_NAME/contact-form.tpl

1

/themes/YOUR_THEME_NAME/contact-form.tpl

Search for <div class=”submit”>

<button type="submit" name="submitMessage" id="submitMessage" class="button btn btn-default button-medium"><span>{l s='Send'}<i class="icon-chevron-right right"></i>$

</div>

and add this:

<button type="submit" name="submitMessage" id="submitMessage" class="button btn btn-default button-medium"><span>{l s='Send'}<i class="icon-chevron-right right"></i>$

</div>

To make it work do:clear cache and recompile your theme → Save and after that undo those options – this worked for me

Apache UserDir in CentOS 7

1 Reply

Quick steps to set it up (I assume you have apache installed):

edit userdir.conf

1	# nano /etc/httpd/conf.d/userdir.conf

#
# UserDir: The name of the directory that is appended onto a user's home
# directory if a ~user request is received.
#
# The path to the end user account 'public_html' directory must be
# accessible to the webserver userid.  This usually means that ~userid
# must have permissions of 711, ~userid/public_html must have permissions
# of 755, and documents contained therein must be world-readable.
# Otherwise, the client will only receive a "403 Forbidden" message.
#
<IfModule mod_userdir.c>
    #
    # UserDir is disabled by default since it can confirm the presence
    # of a username on the system (depending on home directory
    # permissions).
    #
    #UserDir disabled

#
    # To enable requests to /~user/ to serve the user's public_html
    # directory, remove the "UserDir disabled" line above, and uncomment
    # the following line instead:
    # 
    UserDir public_html
</IfModule>

#
# Control access to UserDir directories.  The following is an example
# for a site where these directories are restricted to read-only.
#
<Directory "/home/*/public_html">
    AllowOverride FileInfo AuthConfig Limit Indexes
    Options MultiViews Indexes SymLinksIfOwnerMatch IncludesNoExec
    #Require method GET POST OPTIONS
    Require all granted
</Directory>

# UserDir: The name of the directory that is appended onto a user's home

# directory if a ~user request is received.

# The path to the end user account 'public_html' directory must be

# accessible to the webserver userid. This usually means that ~userid

# must have permissions of 711, ~userid/public_html must have permissions

# of 755, and documents contained therein must be world-readable.

# Otherwise, the client will only receive a "403 Forbidden" message.

# UserDir is disabled by default since it can confirm the presence

# of a username on the system (depending on home directory

# permissions).

#UserDir disabled

# To enable requests to /~user/ to serve the user's public_html

# directory, remove the "UserDir disabled" line above, and uncomment

# the following line instead:

UserDir public_html

</IfModule>

# Control access to UserDir directories. The following is an example

# for a site where these directories are restricted to read-only.

AllowOverride FileInfo AuthConfig Limit Indexes

Options MultiViews Indexes SymLinksIfOwnerMatch IncludesNoExec

#Require method GET POST OPTIONS

Require all granted

</Directory>

restart Apache

Shell

# systemctl restart httpd.service

1

# systemctl restart httpd.service

setup your directory
as normal user enter:

# mkdir /home/your_username/public_html

# chmod 711 /home/your_username

# chown your_username:your_username /home/your_username/public_html

# chmod 755 /home/your_username/public_html

if you use SELinux as root enter:

Shell

# setsebool -P httpd_enable_homedirs true # chcon -R -t httpd_sys_content_t /home/your_username/public_html

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# setsebool -P httpd_enable_homedirs true
# chcon -R -t httpd_sys_content_t /home/your_username/public_html
create simple html page

Shell

# nano /home/your_username/public_html/index.html

1

# nano /home/your_username/public_html/index.html

enter this:

PHP

<html> <body> Hello! </body> </html>

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3
4
5

<html>
<body>
Hello!
</body>
</html>
change ownership of file

Shell

# chmod 644 /home/your_username/public_html/index,html

1

# chmod 644 /home/your_username/public_html/index,html
start your browser and enter this address:

Shell

http://localhost/~your_username/

1

http://localhost/~your_username/

and voila! 😉

Cloning VirtualBox vmdk to vdi

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First of all you have to shutdown VirtualBox machine that you wan’t to clone.
After that create new folder where you wan’t to clone existing vmdk machine to vdi

1	$ mkdir new_vm

After that run this command in terminal:

1	$ VBoxManage clonehd --format VDI old_vm_machine.vmdk new_wm/new_vm_machine.vdi

Wait until the job is done and… that’s all.

Mounting Windows share in CentOS 7

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Today i have to connect to Windows share from CentOS 7. This is how I done it:

1	# yum install samba samba-client cifs-utils

then I have created directory in /mnt

1 2	# cd /mnt # mkdir smb_share

after that:

1	# mount.cifs //ip_address/windows_share smb_share/ -v -o user=username,pass="secretpass",sec=ntlm

That’s all 🙂

ClearOS 6.x , OpenVPN and Windows 10

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Recently I have been in the UK, in a company where many users are connecting to my company server data via VPN and they have told me, that they have problems with OpenVPN client running on Windows 10.

First problem was with OpenVPN client version because, the newest client requires Administrator rights to start. The working version in my case was 32bit and 64bit versions.

The second problem was that after one hour the connection was closing down. Solution for that was easy. I had to only add those two lines

1 2	keepalive 10 60 ping-timer-rem

to openvpn config file – and that’s it. After one hour the connection was still up and runnig !

Cheers!

How to resize VirtualBox disk

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How to resize VirtualBox disk?

1	# VBoxManage modifyhd /path/to/vm/disk.vdi --resize 200000

That’s all 🙂

Prestashop 1.6 max_input_vars

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How to increase max_input_vars on remote hosting? Simple via .htaccess – just add this:

1	php_value max_input_vars 5000

dominik szynk@home

System Administrator daily notes…

Category Archives: how-to

Problem connecting to KVM with Virt-Manager

How-to install cockpit on CentOS 7

How to install MS SQL Server 2017 on CentOS 7

Prestashop 1.6.x.x contact form problem with sending messages.

Apache UserDir in CentOS 7

Cloning VirtualBox vmdk to vdi

Mounting Windows share in CentOS 7

ClearOS 6.x , OpenVPN and Windows 10

How to resize VirtualBox disk

Prestashop 1.6 max_input_vars