Configure CentOS 7

##################################
# Checkout the CentOS version
##################################
cat /etc/redhat-release
cat /etc/os-release

##################################
# Find out hostname and external IP
##################################
hostname
hostname -I
hostname -a

##################################
# Security checks
##################################

# See last logins
last

##################################
# Supervise processes/daemons
##################################
systemctl --list
systemctl | grep httpd
systemctl | grep sshd


##################################
# Updates (apps, kernel...)
##################################
yum check-update
# Do an update to an app or a group of apps or to all
yum update httpd
yum update "Development Tools"
yum update


#Update to the newest kernel (5) and cleanup old kernels
yum -y update
yum -y install yum-plugin-fastestmirror
rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh https://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
yum repolist
yum --enablerepo=elrepo-kernel install kernel-ml
uname -a

# Now configure the grub to boot the newest kernel
awk -F\' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg
sudo grub2-set-default 0
sudo grub2-mkconfig -o /boot/grub2/grub.cfg
reboot

uname -r
yum install yum-utils
package-cleanup --oldkernels

##################################
# Users
##################################
Add a new user and grant him as a sudo (wheel) privileges
useradd bananaspook
passwd bananaspook
su - bananaspook
usermod -aG wheel bananaspook

#List groups for current user
groups

#List all groups
getent group > /etc/initial-group-list
cat /etc/initial-group-list

#Delete a group
sudo groupdel NAME_OF_THE_GROUP_TO_DELETE
#Create a group
sudo groupadd NAME_OF_THE_NEW_GROUP

# Recommended I usually add group named www (or www-data, whatever works for you). To this group I add php daemons, nginx workers etc. It makes life easier with writing to files
sudo groupadd www-data (or www)
# Add a user to a group
sudo usermod -g www-data developer


##################################
# Firewall
##################################
# Install the firewall daemon
sudo yum install firewalld
sudo systemctl start firewalld
sudo firewall-cmd --permanent -add-service=ssh
sudo firewall-cmd --permanent --add-service=ssh
sudo firewall-cmd --permanent --add-service=http
sudo firewall-cmd --permanent --add-service=https
sudo firewall-cmd --permanent --add-service=smtp
sudo firewall-cmd --permanent --list-all
sudo firewall-cmd --get-services
sudo firewall-cmd --reload
#Make it permanent
sudo systemctl enable firewalld



##################################
# ssh keys
##################################
# For new user
ssh developer@IP_OF_THE_SERVER_HERE
ssh-keygen -t rsa -b 4096
# !! execute it from local pc not from server
ssh-copy-id developer@IP_OF_YOUR_SERVER
#this will do:
ssh developer@IP_OF_YOUR_SERVER
cd ~/.ssh
vi authorized_keys
//Press "i" to enter in input mode, paste there your code (usually it's right click of the mouse) and :wq (colon, w, q) it will save and quit from vi 
chmod 600 authorized_keys

#test key
ssh developer@IP_OF_YOUR_SERVER -i path/to/your/PRIVATE/key/file
##################################
# LAMP
##################################
# Install Apache http server
sudo yum install httpd
sudo systemctl start httpd.service

# www-data is the user that web servers on Ubuntu (Apache, nginx, for example) use by default for normal operation. 
# The web server process can access any file that www-data can access. It has no other importance.
# There is apache user instead of www-data in Centos
sudo chown -R apache:www-data /var/www
usermod -a -G www-data your-username

# Install MariaDB
sudo yum install mariadb-server mariadb
sudo systemctl start mariadb
# Remove unsecure configuration
sudo mysql_secure_installation
# Make it permanent
sudo systemctl enable mariadb.service

# Install PHP 7.3
sudo yum install epel-release
sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm
sudo yum install -y yum-utils
sudo yum-config-manager --enable remi-php73
sudo yum install php
php -v

# Composer
curl -sS https://getcomposer.org/installer | php
sudo mv composer.phar /usr/local/bin/composer
sudo chmod +x /usr/local/bin/composer
source ~/.bashrc
################################## 
# git
##################################
# Install latest git from https://www.kernel.org/pub/software/scm/git/
sudo yum remove git
cd /usr/src
wget https://www.kernel.org/pub/software/scm/git/git-2.24.0.tar.gz
tar xzf git-2.24.0.tar.gz
cd git-2.24.0
make prefix=/usr/local/git all
make prefix=/usr/local/git install
# If necessary go the root mode
echo "export PATH=$PATH:/usr/local/git/bin" >> /etc/bashrc
source /etc/bashrc
git -version
git config --global user.name "Jazz"                                                                                                             
git config --global user.email "Your mail"
git config --global core.editor vim
git config --global merge.tool vimdiff

##################################
# Install Latest ruby, rvm, gem
##################################
# rvm (Ruby Version Manager)
curl -sSL https://get.rvm.io | bash -s -- --version latest
sudo printenv | grep -i rvm
# Dependencies
sudo yum install curl gpg gcc gcc-c++ make patch autoconf automake bison libffi-devel libtool patch readline-devel sqlite-devel zlib-devel openssl-devel
source ~/.rvm/scripts/rvm
rvm install 2.5.7
ruby -v
gem -v

# Check ruby versions and remove all ruby versions
rpm -qa | grep -i ruby
sudo yum erase ruby-*

##################################
# sshfs
# Mount droplet locally
##################################
sudo apt-get install sshfs
# local
sudo mkdir /mnt/droplet
sudo chown -R myuser:myuser /mnt/droplet
sshfs [-o allow_other,defer_permissions] [email protected]:/ /mnt/droplet
sshfs [-o allow_other,defer_permissions,IdentityFile=~/.ssh/id_rsa] [email protected]:/ /mnt/droplet
sudo umount /mnt/droplet

# Permanent mounting remote fs
sudo nano /etc/fstab
sshfs#[email protected]:/ /mnt/droplet
#save the changes to /etc/fstab and reboot if necessary.

  
##################################
# Spin up a Jekyll Blog + git revisioning system (ongoing)
##################################
# Local
gem install jekyll
gem install bundler
# if issue with permissions
alias sudo='sudo env PATH=$PATH'
jekyll new myjekyllsite
cd myjekyllsite
# In Amazon AWS Cloud9 you need to pas port 8080 to launch it
jekyll serve --detach --port 8080
# Now go to https://025dbc2f7f4a4dbbaf4caa9fcbe9cc4d.vfs.cloud9.eu-west-1.amazonaws.com/ where 025.. is your ID and tada!
bundle exec jekyll serve --host 198.18.58.2 --port 8080 --detach
#Then we get:server address: http://198.18.58.2:8080/

git remote remove droplet
git remote add droplet myuser@ip:/var/www/repos/jazjek.git
git push droplet master

git pull droplet master --allow-unrelated-histories



##################################
# Deploy jekyll with git hooks
##################################
# Local
jekyll new awesomeblog
cd awesomeblog
# Listen to http://localhost:8080
jekyll serve --port 8080
git init
git add .
git commit -m "Initial commit"


#On Centos server
cd ~/
mkdir repos && cd repos
mkdir awesomeblog.git && cd awesomeblog.git
git init --bare
cd hooks && touch post-receive && nano post-receive

# In post-receive hook paste

`
#!/bin/bash -l

# Install Ruby Gems to ~/gems
export GEM_HOME=$HOME/gems
export PATH=$GEM_HOME/bin:$PATH

GIT_REPO=$HOME/myrepo.git
TMP_GIT_CLONE=$HOME/tmp/myrepo
GEMFILE=$TMP_GIT_CLONE/Gemfile
PUBLIC_WWW=/var/www/myrepo

git clone $GIT_REPO $TMP_GIT_CLONE
BUNDLE_GEMFILE=$GEMFILE bundle install
BUNDLE_GEMFILE=$GEMFILE bundle exec jekyll build -s $TMP_GIT_CLONE -d $PUBLIC_WWW
rm -Rf $TMP_GIT_CLONE
exit
`
# Make it executable
chmod +x post-receive

# Local
git remote add droplet [email protected]:repos/awesomeblog.git
git push droplet master




Journaling
----

24.1
# update repos
yum makecache fast
yum -v repolists

# install php modules required for nextcloud
zip, dom, XMLWriter, libxml, mb multibyte, GD, SimpleXML, PDO

php -v
# version 7.3.11

yum search php73
yum list installed php73*


Upgrade 
https://www.tecmint.com/upgrade-centos-7-to-centos-8/

##################################
# References
##################################
  
# Installation of gitlab MINIMUM 4GB of RAM
https://about.gitlab.com/install/#centos-7
# or if have less memory
https://www.digitalocean.com/community/tutorials/how-to-deploy-jekyll-blogs-with-git
# sshfs
https://www.digitalocean.com/community/tutorials/how-to-use-sshfs-to-mount-remote-file-systems-over-ssh
# jekyll. rsync
https://davesworld.blog/publish-to-jekyll-blog-via-local-jekyll-server-and-git-enabled-web-hosting-account