Facebook March 2018: Can't Load URL: The domain of this URL isn't included in the app's domains

In March 2018 Facebook will invalidate calls from URIs not listed in the Valid OAuth redirect URIs requiring us to Enable Strict Mode for Redirect URIs.

If you tried all the solutions available googling about it without success you can try this fix too.

To fix this problem 

a) Update and Enable Strict Mode and HTTPS in the app's settings.

b) Add in the app settings the valid OAuth redirect URIs the URL used to interact with Facebook SDK. 

c) Change this piece of code:

$accessToken = $helper->getAccessToken();

In:

$accessToken = $helper->getAccessToken('myurl_callback');

    } catch(Facebook\Exceptions\FacebookResponseException $e) {

...

}

That's all, this fixed the problem.

How to access git using a key pair

The following method will help you accessing your repository using a keypair file. 

This could be usefull when you are using Amazon server with a keypair file without a password otherwise you don't need to follow this guide.

1) Upload/Copy the keypair file (.pem) on your  ~/.ssh/ directory

$ cp cert.pem  ~/.ssh/.

2) Move on your ssh directory and change the permissions on the file

$ chmod 400 cert.pem

3) Create or update your  ~/.ssh/config file

$ nano  ~/.ssh/config

4) Copy and update the rows below with the correct hostname, user and identifyfile:

Host git

Hostname www.example.com

User ubuntu

IdentityFile /pathtossh/ssh/cert.pem

5) Clone the repository

$ git clone git:/path/to/remoteproject/repository.git

Done!

If you need to copy and overwrite the entire cloned project inside another directory you could you the command below:

$ \cp -R source destination

To update your projects and use the new address you need to open the project's git config file

$ nano ~/path/to/remoteproject/.git/config 

After that you have to change the url line:

git:path/to/remoteproject/repository.git

Fix TImezone on RDS Mysql MariaDB

In this post i will explain the steps to fix the timezone UTC "issue" on RDS (if we can call it an issue...). If you need to do that you have to follow this guide. I used MariaDB as mysql fully compatible database.

1) Connect to your RDS instance via shell or client

2) Create the following stored procedure 
DELIMITER | CREATE PROCEDURE mysql.store_time_zone () IF NOT (POSITION('rdsadmin@' IN CURRENT_USER()) = 1) THEN SET SESSION time_zone = 'Europe/Rome'; END IF | DELIMITER ; 

3) Grant permission to the user 
GRANT EXECUTE ON PROCEDURE `mysql`.`store_time_zone` TO 'usersql'@'%'; 

4) Create a new parameter group with eg. Timezonefix 

5) In the search bar search for "init_connect" 

6) Insert the following value: CALL mysql.store_time_zone 

7) Go to your rds instance and modify it selecting the new parameters group 

8) Apply immediatly 

9) Reboot your instance and the job is done.

Parallels Plesk Can't Create/Write to file /tmp/#sql_ MYD (Errcode 17)

To fix this error on parallel plesk, you need to remove the /tmp/#sql_xxx.MYD file from the tmp directory in your root.

SSH exchange identification: Connection closed by remote host [Solved]

If you will face this problem when connecting through ssh:
SSH exchange identification: Connection closed by remote host.
Maybe your server was under a brute force attack. To solve this problem in an easy way you could install denyhosts. On Centos server yum install denyhosts. Edit /etc/hosts.allow and insert the IP that you never want to block. Edit /etc/denyhosts.conf and check your distribution default conf. After that, simply start denyhosts service denyshosts start Stay tuned.

[Solved] Vsftpd with chrooted users not restart on Ubuntu 12.04

If you face this error on your Ubuntu 12.04 500 OOPS: vsftpd: refusing to run with writable root inside chroot()

Once edited the /etc/passwd to chroot the user with /bin/rbash and after changed permissions on the directory that will be the ftp home directory of the user, to enable vsftpd without errors on starting the service you need to follow the steps below:

1) wget http://http.us.debian.org/debian/pool/main/v/vsftpd/vsftpd_3.0.2-3_amd64.deb

2) dpkg -i vsftpd_3.0.2-2_amd64.deb

3) echo "allow_writeable_chroot=YES" >> /etc/vsftpd.conf

4) /etc/init.d/vsftpd restart

Now you will be able to restart your vsftpd service without any other issue.

Linux adduser user@domain.tld with @ or . inside the userid and use it as an FTP account

If you want to add a new user to your linux box and it not contains any special char like an '@' or '.' there is no problem. In the other case you could not find an answer simply googling around. For this reason i have to make some tests on different kind of server (dedicated and vps ones). 

Via plesk or others gui i didn't find a way to add user with special chars inside the username, also via shell i had some problems with that. 

The final solution for me was using webmin or follow the instructions below:

# groupadd ftpusers
# adduser 1234455 -d /home/1234455 -G ftpusers
# passwd 1234455
# type and retype password
# chown 1234455:ftpusers /home/1234455/

Well, now you have a user without @extdomain.tld so to do that you have to modify two files:

/etc/passwd
/etc/shadow

edit in passwd:

old one
1234455:x:10005:505::/home/1234455:/bin/false
new one
1234455@extdomain.tld:x:10005:505::/home/1234455:/bin/false

edit the same in the shadow and be carefull when do that.

After doing these hacks you could access to your home directory via ftp using 1234455@extdomain.tld :)

[SOLVED] My website is unreachable but SSH still works Centos Linux

Hi all,
if suddenly your websites becomes unavailables or unreachables instead your IP/SSH still works than you could try this tricks that works for me in some situations on redhat Centos.

If you could reach your IP but not your website, then there's something wrong - maybe - with DNS configuration or FIREWALL rules.
If you reviewed your DNS configuration and you tried to restart dns service through:

service named restart

with no success, maybe the problem could be the linux firewall iptables.
So, type these 2 line into your bash 


service iptables stop

nano /etc/sysconfig/iptables

To check if the server accept incoming connection on the 80 port and 443 port (http and https) you have to verify the iptables config files in /etc/sysconfig/iptables.

# Generated by iptables-save v1.4.7
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [26:2600]
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
-A INPUT -p icmp -j ACCEPT
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 8443 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
COMMIT
# Completed

If port 80 and 443 not exists you have to add these two lines to your VPS iptables config file and it will accept new incoming connection.


-A INPUT -p tcp -m state --state NEW -m tcp --dport 80 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 443 -j ACCEPT

Now type in your console:

service iptables start

Now you could check if your website is again available and reachable through the 80 and 443 port.

This works fine on RedHat Centos Linux distribution.

If you have problem listing your directory via FTP so type this in your ssh:

iptables -A INPUT -p tcp --dport 21 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

Stay tuned.

Drupal 6 Pages and Feed RSS: set the offset and item's pagination.

If you have to change dinamically the number of items that are displayed on your feed page or do you need to set their offset via Drupal 6 Feed Rss Views Module, than this post could helps.

After googling for a couple of hours without find any solution to this issue, i tried to solve it by myself.
I would like to pass custom number of items and their offset as arguments of an url.

Something like this

http://www.yourdrupalwebsite.com/rss.xml?items-limit=5&items-offset=5

This page is a custom feed page created by the drupal's admin side .



/admin/build/views/edit/(rss-feed) (in my case)


After that you'll have to use this little hack that change a little piece of code inside the file

modules/views/plugins/views_plugin_display.inc

I found this piece of code on the line 1861. So i changed the following default settings:


$this->view->set_pager_element($this->get_option('pager_element'));$this->view->set_items_per_page($this->get_option('items_per_page'));
$this->view->set_offset($this->get_option('offset'));


and i replaced them with:


$this->view->set_items_per_page(($_GET['items-limit'] > 0) ? $_GET['items-limit'] : $this->get_option('items_per_page'));
$this->view->set_offset(($_GET['items-offset'] > 0) ? $_GET['items-offset'] :$this->get_option('offset'));


Save the file and you'll be ready to call your feed page with your custom arguments with it.

http://www.yourdrupalwebsite.com/rss.xml?items-limit=5&items-offset=5


and check the response.


Note:
You need to filter and sanitize your $_GET input values for security reasons.



Enjoy

[solved] MYSQL Can't start server: can't create PID file: No space left on device

Hi all dear friends of HTV, today i will explain how to fix a bug that affects MySQL server running on a Centos 5.0 Box.

The error in the /var/log/mysqld is :

Can't start server: can't create PID file: No space left on device MYSQL

If your MySQL can't restart and the /var/log/mysqld log show you this message, well, most probably you finished your partition space available.

To solve this issue you have to do the following steps:

1) check your partitions with the command:

df -h

this command will output your partitions conf:

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              58G   53G   0  100% //dev/sda1              99M   12M   83M  13% /boot
/dev/sda2              58G   13G   42G  24% /media/sda2


Please notice that the full size of /dev/sda2 partition is 58GB, the used space is 53GB and the available once is 0 (100% use).


2) Now that we are aware of this we have to find the files (often they are huge log files) that fill our partition. So we could take a look in the /var directory or /tmp directory to find and move some of them via rsync into another partition or we could free some space deleting older logs and files not needed. (Be carefully when you are doing that).
To find big files over your system you could execute this command via ssh


 du -h --max-depth=3 /* > mybigfiles.txt


This command will write in the file all the output of the command du -h -max-depth=3 in the file named mybigfiles.txt all showing all the dirs in the system with theirs current size.

Navigating through this file you could find which directories are the biggest ones and after that you have to clean them before restarting MySQL server.

First of all do this command via cmd line:

yum clean all

To empty cached sources and packages in your RH distro.

Then if you would like to remove, for example, all the log files in a dir older then 3 days you have to execute the command :

find /var/log/mydirectorywithbigfiles -type f -mtime +3 -exec rm {}

or use this bash script

#!/bin/bash

find /var/log/mydirectorywithbigfiles -type f -mtime +3 -exec rm {} \;

  

that use a combo of find command and -exec rm {} that removes all the files inside that dir.

After that please execute again the command to check if you freed up some disk space.


df -h

Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              58G   13G   42G  24% //dev/sda1              99M   12M   83M  13% /boot
/dev/sda2              58G   13G   42G  24% /media/sda2



Once finished, please restart your Mysqld daemon, via /etc/init.d/mysqld start.


Leave a comment if you liked this guide.


HTV

Setup and configure SSL / HTTPS with Verisign CA on Linux CENTOS [step by step tutorial]

If you need to install SSL certificates on your server web you have to follow this step by step tutorial about Verisign's certificate installation. (i get a 30 days trial cert to test it)

1) Install mod_ssl with command:

yum install mod_ssl


2) Create a directory in which we save our key files and move to it

mkdir /home/ssl/
cd /home/ssl/

3) Execute the follow command on a single line:

openssl x509 -req -days 365 -in www.domain_name.com.csr -signkey secure.domain_name.com.key -out www.domain_name.com.crt


4) Copy the key into .secure file.

cp www.domain_name.com.key www.domain_name.com.key.secure


5) Execute the command to generate the file

openssl rsa -in www.domain_name.com.secure -out www.domain_name.com.key

6) Type the following command to generate a private key that is file encrypted. You will be prompted for the password to access the file and also when starting your webserver. Warning: If you lose or forget the passphrase, you must purchase another certificate.

openssl genrsa -des3 -out www.domain_name.com.key 1024


7) You could also create a private key without file encryption if you do not want to enter the passphrase when starting your webserver:

openssl genrsa -out www.domain_name.com.key 1024

Note: i recommend that you name the private key using the domain name that you are purchasing the certificate for ie domainname.key

8) Type the following command to create a CSR with the RSA private key (output will be PEM format):

openssl req -new -key www.domain_name.com.key -out www.domain_name.com.csr

* Note: You will be prompted for your PEM passphrase if you included the "-des3" switch in step 6.

* 2nd Note: When creating a CSR you must follow these conventions. Enter the information to be displayed in the certificate. The following characters can not be accepted: < > ~ ! @ # $ % ^ * / \ ( ) ?.,&

8) Put the output of cat command in a txt file.

cat www.domain_name.com.csr > mycert.txt


9) Copy source from that file mycert.txt and paste it into the Verisign's CSR form validation.

10) wait for the Versign's confirmation email with the browser cert file that will be send to you within 24 hours.


Once you received that email you'll have to download and install the Test Root CA Certificate into your browser. This is the procedure to follow:

11.1) Save the test root CA certificate from Verisign website on a file with .cer extension (ex. browser.cer) and install it into your browser.

11.2) Copy the intermediate CA certificate content from verisign website into a file called (intermediate.crt)

11.4) Copy the certificate that you received with the email in a file called (public.crt)

11.5) Copy the content of the bundle (two cert) into a file ca-cert.crt

-----BEGIN CERTIFICATE-----
MIIEVzCCAz+gAwIBAgIQFoFkpCjKEt+rEvGfsbk1VDANBgkqhkiG9w0BAQUFADCB
.....
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
IEVzCCAz+gAwIBAgIQFoFkpCjKEt+rEvGfsbk1VDANBgkqhkiG9w0BAQUFADCB
......
-----END CERTIFICATE-----

11.6) Copy all .crt files (public.crt, intermediate.crt, ca-bundle.crt) into /etc/pki/tls/certs/ on your centos distribution.

11.7) Copy www.domain_name.com.key to /etc/pki/tls/private/ folder

11.8) Now you could check virtual host and insert these lines of code into your /etc/httpd/conf.d/ssl.conf file:


DocumentRoot /var/www/html/yourwebdir
ServerPath /var/www/html/yourwebdir
ServerName www.domain_name.com:443
ServerAlias *.domain_name.com:443
DirectoryIndex index.html index.php index.shtml
ErrorLog logs/ssl_error_log
TransferLog logs/ssl_access_log
LogLevel warn
SSLEngine on
SSLProtocol all -SSLv2
SSLCipherSuite ALL:!ADH:!EXPORT:!SSLv2:RC4+RSA:+HIGH:+MEDIUM:+LOW
SSLCertificateFile /etc/pki/tls/certs/public.crt
SSLCertificateKeyFile /etc/pki/tls/private/www.domain_name.com.key
SSLCertificateChainFile /etc/pki/tls/certs/intermediate.crt
SSLCACertificateFile /etc/pki/tls/certs/ca-bundle.crt

SSLOptions +StdEnvVars

SSLOptions +StdEnvVars
SetEnvIf User-Agent ".*MSIE.*" \
nokeepalive ssl-unclean-shutdown \
downgrade-1.0 force-response-1.0

CustomLog logs/ssl_request_log \
"%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"



12) Now restart apache /etc/init.d/httpd restart


If everything goes [OK] you could check your https and ssl at your web address: https://www.domain_name.com


Good luck!

Add a custom script as a daemon on reboot of a redhat centos server

To enable a custom script in a redhat centos server linux box you have to follow those simple steps.
This is useful when you have to start a server process that don't return anything..
One example is openoffice server aka (soffice).
Suppose you have two files.
The first file A call the second file named B-so
The file A contains a code like this

# Source function library.
. /etc/rc.d/init.d/functions

[ -f /usr/local/sbin/B-so ] || exit 0


prog="B-so"
start() {
echo -n $"Starting $prog: "
daemon /usr/local/sbin/B-so 1> /dev/null 2> /dev/null &
RETVAL=$?
echo
return $RETVAL
}

stop() {
if test "x`ps aux | grep B-so | grep -v grep | awk '{ print $2 }'`" != x; then
echo -n $"Stopping $prog: "
killproc B-so
killall processname
echo
fi
RETVAL=$?
return $RETVAL
}

case "$1" in
start)
start
;;

stop)
stop
;;

status)
status B-so
;;

restart)
stop
start
;;

*)
echo $"Usage: $0 {start|stop|restart|status}"
exit 1

esac

exit $RETVAL


Copy the file A in the directory /etc/init.d/

Copy the second file B.so in the dir /usr/local/sbin/
The file B-so contains a code like this:


. /etc/rc.d/init.d/functions

LOG="/root/mail2fax/log/safe-B.log"


while :
do
...done some stuff ...
done


After that you have to add a line with the path to the service to start in the /etc/rc.local.

Check if permissions on those two files are set on 0755,then you could reboot your server and verify if the service start successfully.

img credits wmliu

Install Odf-converter-integrator on Linux Redhat Centos

Hi all, today i will explain to you how to install odf-converter-integrator, an open tool to convert Microsoft Office 2007 files with .docx .pptx, .xlsx extensions in open file format ODF , you have to download the software rpm into a temp dir. So change your current dir to /tmp/ dir and launch the command:

1) Launch:
wget http://linuxsoft.cern.ch/cern/slc5X/x86_64/yum/extras/odf-converter-integrator-0.2.3-2.i386.rpm

2) Execute the command:
rpm -ivh odf-converter-integrator-0.2.3-2.i386.rpm

3) When process completed the installation you could run your cmd for conversion
OdfConverter somefile.docx

If you use this tool with OpenOffice you could do very intersting different kinds of conversion...

[Solved] DocumentConverter.py via PHP on Linux RedHat Centos

This is a guide to fix the use of PYODConverter on linux RedHat Centos 5 box users.
If you wanna use DocumentConverter.py written by artofsolving, you have to follow those steps.

1)Install openoffice on your linux box or verify installation through commands:
Install Packages

yum install openoffice.org-xxx.

Check Packages

yum list | grep "openoffice".


2)Install python-uno bridge

3)Download DocumentConverter.py

4)Add the following line below "import uno"...

import sys
sys.path.append("/usr/lib/openoffice.org/program")


5)Run openoffice like a service with -headless and -nofirtstartwizard options.


/usr/lib/openoffice.org/program/soffice -nologo -nofirststartwizard -headless -norestore -invisible "-accept=socket,host=localhost,port=8100,tcpNoDelay=1;urp;"




The port 8100 must be the same for client and server obviously.


If you execute this php code



$cmd = "/usr/bin/python /var/www/html/DocumentConverter.py inputfile $outputfile.pdf 2>&1 | tee /var/www/html/mylog.txt"; // tee used to log output and errors of cmd
exec($cmd, $results);
printf("Exec Output: {".print_r($results).";}\n"); //print results of exec command


you'll probably get this error:


[Java framework] Error in function createSettingsDocument (elements.cxx).javaldx failed!
And other permissions problems on tmp dirs.

To solve this, simply add into your php script those lines of code

if (!file_exists("/tmp/ooohomedir"))
{
mkdir("/tmp/ooohomedir");
chmod("/tmp/ooohomedir", 0777);
}
putenv("HOME=/tmp/ooohomedir");



If you have another workaround about this please leave a comment below.
C u.

How to code a wordpress plugin.

Hi everybody. I would like to bookmark this screencast tutorial that explains how to build a simple wordpress plugin.

You could find the complete tutorial on tutplus

Project Natal & Lionhead Milo Project @ E3 2009

Here we are. These two videos demonstrates that the future of playing videogames is nearby.
Microsoft presents Xbox360 with new amazing devices at the E3 2009.
No controllers, no wires, facial recognition, voice and body recognition .
This and more other things are explained in the videos that follows.
The payoff says:
XBOX360, The only experience that you needs is your life experience.
Have a nice view.

Project Natal

Lionhead Milo Project

25 years mac video

January 24th 2009 marks the 25th anniversary for the Apple Macintosh.
In the far 1984 begun the Apple story.


happy birthday mac.

Obama president: inauguration 2009

Welcome Dear Mr. President Obama.
We believe in You.

Antenna Wireless Hacks

This video explains the easiest and cheapest way to hacks your wi-fi antennas.
The final result is that you could double signal strength and antenna's range for few cents and get a more omni-directional output (less fiddling with exact antenna placement) and a gain of 5 dB.





More infos and a step by step guide to hack your wifi antenna.

An amazing video that explains the evolution of internet.



History of the Internet from PICOL on Vimeo.

Credits to http://www.lonja.de/