View SSL certificate details
openssl x509 -in ssl.crt -text -noout
To get SSL certificate details of a web site
timeout 5 echo QUIT | openssl s_client -connect serverok.in:443 2>&1 | openssl x509 -noout -text
Here are some dedicated server providers. If you need any recommendations or found a service provider that you think useful, contact me at [email protected]
These servers are very cheap. You can’t get a decent VPS for this price. Only use them for personal sites. Also make sure you take regular backups.
See list of Cloud Hosting Providers
To install PostgreSQL on Ubuntu/Debian, run
apt-get install -y postgresqlStart it with
service postgresql startBy default user “postgres” have full access on PostgreSQL. To create a user, run
su postgres
createuser -P USERNAMETo create a database, run
createdb -T template0 -E UTF8 -O USERNAME DBNAMEYou can see help with
postgres@ok-vm:~$ createdb --help
createdb creates a PostgreSQL database.
Usage:
createdb [OPTION]... [DBNAME] [DESCRIPTION]
Options:
-D, --tablespace=TABLESPACE default tablespace for the database
-e, --echo show the commands being sent to the server
-E, --encoding=ENCODING encoding for the database
-l, --locale=LOCALE locale settings for the database
--lc-collate=LOCALE LC_COLLATE setting for the database
--lc-ctype=LOCALE LC_CTYPE setting for the database
-O, --owner=OWNER database user to own the new database
-T, --template=TEMPLATE template database to copy
-V, --version output version information, then exit
-?, --help show this help, then exit
Connection options:
-h, --host=HOSTNAME database server host or socket directory
-p, --port=PORT database server port
-U, --username=USERNAME user name to connect as
-w, --no-password never prompt for password
-W, --password force password prompt
--maintenance-db=DBNAME alternate maintenance database
By default, a database with the same name as the current user is created.
Report bugs to <[email protected]>.
postgres@ok-vm:~$ To install x2Go server in Ubuntu, run
add-apt-repository ppa:x2go/stable apt-get update apt-get -y install x2goserver x2goserver-xsession
if you don’t have xfce, install it with
apt -y install xfce4
See x2go, add-apt-repository
When i try connect to a server, i get error
root@ok:~# ssh [email protected]
Unable to negotiate with 50.62.71.1 port 22: no matching host key type found. Their offer: ssh-dss
root@ok:~# Same happens with scp
root@ok:~# scp [email protected]:/var/chroot/home/content/83/13319983/html.tar .
Unable to negotiate with 50.62.71.1 port 22: no matching host key type found. Their offer: ssh-dss
root@ok:~#To fix this, add -oHostKeyAlgorithms=+ssh-dss to the command.
Example
ssh -oHostKeyAlgorithms=+ssh-dss [email protected]To list all supported ciphers, run
ssh -Q cipherYou can use -c option to change chiper.
ssh -c aes128-cbc [email protected]To install ioncube Debian 8, first download the ioncube loader from
http://www.ioncube.com/loaders.php
cd /usr/local/src wget https://downloads.ioncube.com/loader_downloads/ioncube_loaders_lin_x86-64.tar.gz tar xvf ioncube_loaders_lin_x86-64.tar.gz cd ioncube/
This folder have loader for several PHP versions, find the PHP version you have with command
php -v
By default Debian 8 come with PHP 5.6. The file you need to use for PHP 5.6 is ioncube_loader_lin_5.6.so
You need to copy this file to PHP extension directory. To find this, run
# php -i | grep extension_dir extension_dir => /usr/lib/php5/20131226 => /usr/lib/php5/20131226 #
Lets copy ioncube loader file to extension diretcory
cp /usr/local/src/ioncube/ioncube_loader_lin_5.6.so /usr/lib/php5/20131226
create file
echo "zend_extension=ioncube_loader_lin_5.6.so" > /etc/php5/apache2/conf.d/01-ioncube.ini ln -s /etc/php5/apache2/conf.d/01-ioncube.ini /etc/php5/cli/conf.d/01-ioncube.ini
Restart Apache web server
service apache2 restart
You can verify ioncube module installed with
root@myterrarium-vm:~# php -m | grep ion ionCube Loader Reflection session the ionCube PHP Loader (enabled) + Intrusion Protection from ioncube24.com (unconfigured) root@myterrarium-vm:~#
Install pip
On CentOS
wget https://bootstrap.pypa.io/get-pip.py python get-pip.py
On Ubuntu
apt install python-pip
On Ubuntu, python3
apt install python3-pip
Install a python module from github using pip
cd /opt/bench git clone https://github.com/frappe/bench bench-repo
Now run
pip install -e bench-repo
Install modules from requirments.txt
pip install -r requirements.txt
To create requirements.txt file, run
pip freeze > requirements.txt
On CentOS, the wheel group allows users in this group to run commands as user root with sudo.
To add a user to the wheel group, run
usermod -aG wheel USERNAMEOn Ubuntu/Debian, use
usermod -aG sudo USERNAMERemove a User from Group
deluser USERNAME GROUPExample
root@ip-172-31-56-4:~# deluser designware sudo
Removing user `designware' from group `sudo' ...
Done.
root@ip-172-31-56-4:~# Here we remove user designware from group sudo.
To remove a user from all secondary groups, run
usermod -G "" USERNAMETo disable SSH login, run
usermod -s /sbin/nologin USERNAMEFor example
usermod -s /sbin/nologin mysqlYou can find latest version of Node.js at
To install Node.js on CentOS 7/8
Add node.js repository
NodeJS 12.x
curl -sL https://rpm.nodesource.com/setup_12.x | bash -
NodeJS 11.x
curl -sL https://rpm.nodesource.com/setup_11.x | bash -
NodeJS 10.x
curl -sL https://rpm.nodesource.com/setup_10.x | bash -
NodeJS 8.x
curl -sL https://rpm.nodesource.com/setup_8.x | bash -
NodeJS 6.x
curl -sL https://rpm.nodesource.com/setup_6.x | bash -
Install node.js with
yum -y install nodejs
For npm to install native modules, install dev tools
yum install gcc-c++ make
Or
yum groupinstall 'Development Tools'
See Node.Js
Connect to a server
lftp -u USER,PASSWORD SERVER_IP
Disable SSL
set ftp:ssl-allow false set ssl:verify-certificate no
Enable Active FTP mode
set ftp:passive-mode off
Here are some commands used to investigate server load/performance issue.
uptime free -m top atop htop
Checking logs
dmesg | tail
iostat
vmstat 1
sar
sar
iostat
iostat iostat -xz 1
pidstat/mpstat
pidstat 1 mpstat -P ALL 1