#!/bin/bash
#
# This script provides information regarding when kernel-related packages
# are installed on a system by querying information from the RPM database.
#

# Variables
PACKAGETYPE=kernel
PACKAGES=$(rpm -qa | grep $PACKAGETYPE)

# Loop through packages
for PACKAGE in $PACKAGES; do
    # Determine package install date and time
    INSTALLEPOCH=$(rpm -q --qf "%{INSTALLTIME}\n" $PACKAGE)

    # RPM reports time in epoch, so need to convert
    # it to date and time format with date command
    INSTALLDATETIME=$(date -d @$INSTALLEPOCH)

    # Print message
    echo "$PACKAGE was installed on $INSTALLDATETIME"
done

mkdir /dbbackup

$ mysql --skip-column-names -E -uroot -predhat -e 'SHOW DATABASES' | grep -v '^*' | grep -v '^information_schema$' | grep -v '^performance_schema$'
JDGCACHESTORE
apaccustomers
brokerinfo
eucustomers
matdb
mysql
products
test
uscustomers

#!/bin/bash

# Variables
DBUSER=root
DBPASSWORD=redhat
FMTOPTIONS='--skip-column-names -E'
COMMAND='SHOW DATABASES'
BACKUPDIR=/dbbackup

# Backup non-system databases
for DBNAME in $(mysql $FMTOPTIONS -u$DBUSER -p$DBPASSWORD -e "$COMMAND" | grep -v ^* | grep -v information_schema | grep -v performance_schema); do
    echo "Backing up \"$DBNAME\""
    mysqldump -u$DBUSER -p$DBPASSWORD $DBNAME > $BACKUPDIR/$DBNAME.dump
done

# Add up size of all database dumps
for DBDUMP in $BACKUPDIR/*; do
    SIZE=$(stat --printf "%s\n" $DBDUMP)
    TOTAL=$[ $TOTAL + $SIZE ]
done

# Report name, size, and percentage of total for each database dump
echo
for DBDUMP in $BACKUPDIR/*; do
  SIZE=$(stat --printf "%s\n" $DBDUMP)
  echo "$DBDUMP,$SIZE,$[ 100 * $SIZE / $TOTAL ]%"
done

$ dbbackup
Backing up "JDGCACHESTORE"
Backing up "apaccustomers"
Backing up "brokerinfo"
Backing up "eucustomers"
Backing up "matdb"
Backing up "mysql"
Backing up "products"
Backing up "test"
Backing up "uscustomers"

/dbbackup/apaccustomers.dump,7851,1%
/dbbackup/brokerinfo.dump,3239,0%
/dbbackup/eucustomers.dump,9697,1%
/dbbackup/JDGCACHESTORE.dump,4083,0%
/dbbackup/matdb.dump,7275,1%
/dbbackup/mysql.dump,514266,89%
/dbbackup/products.dump,15940,2%
/dbbackup/test.dump,3929,0%
/dbbackup/uscustomers.dump,9928,1%

#!/bin/bash

echo "$0 has $# arguments."

# Optionally, use 'for ARG in "$*"; do' will output the arguments in one line
for ARG in "$@"; do
    echo $ARG
done

$ ./showargs foo bar zoo
./showargs has 3 arguments.
foo
bar
zoo

#!/bin/bash

[ 1 -eq 1 ]; echo $?;
[ 1 -ne 1 ]; echo $?;
[ 8 -gt 2 ]; echo $?;
[ 2 -ge 2 ]; echo $?;
[ 2 -lt 2 ]; echo $?;
[ 1 -lt 2 ]; echo $?;

[ abc = abc ]; echo $?;
[ abc == def ]; echo $?;
[ abc != def ]; echo $?;

STRING=''; [ -z "$STRING" ]; echo $?;
STRING='abc'; [ -n "$STRING" ]; echo $?;

[ 2 -gt 1 ] && [ 1 -gt 0 ]; echo $?;
[ 2 -gt 1 ] && [ 1 -gt 2 ]; echo $?;
[ 2 -gt 1 ] || [ 1 -gt 2 ]; echo $?;
[ 0 -gt 1 ] || [ 1 -gt 2 ]; echo $?;

#!/bin/bash

# Variables
VHOSTNAME=$1
TIER=$2
HTTPDCONF=/etc/httpd/conf/httpd.conf
VHOSTCONFDIR=/etc/httpd/conf.vhosts.d
DEFVHOSTCONFFILE=$VHOSTCONFDIR/00-default-vhost.conf
VHOSTCONFFILE=$VHOSTCONFDIR/$VHOSTNAME.conf
WWWROOT=/srv
DEFVHOSTDOCROOT=$WWWROOT/default/www
VHOSTDOCROOT=$WWWROOT/$VHOSTNAME/www

# Check arguments
if [ "$VHOSTNAME" = '' ] || [ "$TIER" = '' ]; then
    echo "Usage: $0 VHOSTNAME TIER"
    exit 1
else
    case $TIER in
        1)    VHOSTADMIN='basic_support@example.com'
              ;;
        2)    VHOSTADMIN='business_support@example.com'
              ;;
        3)    VHOSTADMIN='enterprise_support@example.com'
              ;;
        *)    echo "Invalid tier specified."
              exit 1
              ;;
        esac
fi

# Create conf directory one time if non-existent
if [ ! -d $VHOSTCONFDIR ]; then
    mkdir $VHOSTCONFDIR

    if [ $? -ne 0 ]; then
        echo "ERROR: Failed creating $VHOSTCONFDIR."
        exit 1
    fi
fi

# Add include one time if missing
grep -q '^IncludeOptional conf\.vhosts\.d/\*\.conf$' $HTTPDCONF

if [ $? -ne 0 ]; then
    # Backup before modifying
    cp -a $HTTPDCONF $HTTPDCONF.orig
    echo "IncludeOptional conf.vhosts.d/*.conf" >> $HTTPDCONF

    if [ $? -ne 0 ]; then
        echo "ERROR: Failed adding include directive."
        exit 1
    fi
fi

cat <<DEFCONFEOF > $DEFVHOSTCONFFILE
<VirtualHost _default_:80>
  DocumentRoot $DEFVHOSTDOCROOT
  CustomLog "logs/default-vhost.log" combined
</VirtualHost>
<Directory $DEFVHOSTDOCROOT>
  Require all granted
</Directory>
DEFCONFEOF

# Check for default virtual host
if [ ! -f $DEFVHOSTCONFFILE ]; then
    cat <<DEFCONFEOF > $DEFVHOSTCONFFILE
<VirtualHost _default_:80>
  DocumentRoot $DEFVHOSTDOCROOT
  CustomLog "logs/default-vhost.log" combined
</VirtualHost>

<Directory $DEFVHOSTDOCROOT>
  Require all granted
</Directory>
DEFCONFEOF
fi

if [ ! -d $DEFVHOSTDOCROOT ]; then
  mkdir -p $DEFVHOSTDOCROOT
  restorecon -Rv /srv/
fi

cat <<CONFEOF > $VHOSTCONFFILE
<VirtualHost *:80>
  ServerName $VHOSTNAME
  ServerAdmin $VHOSTADMIN
  DocumentRoot $VHOSTDOCROOT
  ErrorLog "logs/${VHOSTNAME}_error_log"
  CustomLog "logs/${VHOSTNAME}_access_log" common
</VirtualHost>

<Directory $VHOSTDOCROOT>
  Require all granted
</Directory>
CONFEOF

# Check for virtual host conflict
if [ -f $VHOSTCONFFILE ]; then
    echo "ERROR: $VHOSTCONFFILE already exists."
    exit 1
elif [ -d $VHOSTDOCROOT ]; then
    echo "ERROR: $VHOSTDOCROOT already exists."
    exit 1
else
    cat <<CONFEOF > $VHOSTCONFFILE
<Directory $VHOSTDOCROOT>
  Require all granted
  AllowOverride None
</Directory>

<VirtualHost *:80>
  DocumentRoot $VHOSTDOCROOT
  ServerName $VHOSTNAME
  ServerAdmin $VHOSTADMIN
  ErrorLog "logs/${VHOSTNAME}_error_log"
  CustomLog "logs/${VHOSTNAME}_access_log" common
</VirtualHost>
CONFEOF

    mkdir -p $VHOSTDOCROOT
    restorecon -Rv $WWWROOT
fi

# Check config and reload
apachectl configtest &> /dev/null

if [ $? -eq 0 ]; then
    systemctl reload httpd &> /dev/null
else
    echo "ERROR: Config error."
    exit 1
fi

mkvhost test.example.com 2

# for i in tom jerry alias natasha mario harry ; do echo $i >> sample.users ; done
# cat sample.users
tom
jerry
alias
natasha
mario
harry

#!/bin/bash
if [ $# -ne 1 ]; then
   echo 'Usage: /root/makeusers <userfile>'
   exit 1
fi
if [ ! -f "$1" ]; then
   echo "Input file not found"
   exit 2
fi
   while read line
   do useradd -s /bin/false $line
   done < $1

# chmod +x makeusers

# ./makeusers
Usage: /root/makeusers <userfile>

# ./makeusers no.exsit
Input file not found

# ./makeusers sample.users && tail -n 6 /etc/passwd
tom:x:1001:1001::/home/tom:/bin/false
jerry:x:1002:1002::/home/jerry:/bin/false
alias:x:1003:1003::/home/alias:/bin/false
natasha:x:1004:1004::/home/natasha:/bin/false
mario:x:1005:1005::/home/mario:/bin/false
harry:x:1006:1006::/home/harry:/bin/false

#!/bin/bash
case $1 in
     all)
       echo "none" ;;
     none)
       echo "all" ;;
     *)
      echo "all|none" ;;
esac

# chmod +x script.sh

# /root/script.sh all
none

# /root/script.sh none
all

# /root/script.sh
all|none

# /root/script.sh xxx
all|none