/etc/default/grub

getconf LONG_BIT

lscpu | egrep 'Byte Order'

file /bin/ps # LSB for Little Endian

netstat -antp

dd if=/dev/urandom of=50MB.bin bs=1M count=50

ls --help | grep -E '[-][tr]\b'

service nginx status
/etc/init.d/nginx status

update-rc.d

echo 'CentOS'
chkconfig nginx on
chkconfig nginx

export count=2
ps aux --sort=-pcpu | head -n $count
ps aux --sort=-rss | head -n  $count

ssh root@10.2.3.6 'racadm serveraction  powerup'

find /home -iname tecmint.txt

export http_proxy=http://192.168.4.10:7778/
export https_proxy=$http_proxy 
export no_proxy="localhost,127.0.0.1,192.168.*.*,10.*.*.*"
export ftp_proxy=$http_proxy
export rsync_proxy=$http_proxy

echo 'ubuntu set apt-get proxy'
cat /etc/apt/apt.conf
#Acquire::http::Proxy "http://Username:Password@proxy.foo.bar.edu.au:8080";

# detect proxy type
nmap -sV -p5201 127.0.0.1

set -h

curl -H 'Authorization: token INSERT_ACCESS_TOKEN_HERE' \
    -H 'Accept: application/vnd.github.v3.raw' -O -L \
    https://api.github.com/repos/owner/repo/contents/path

echo $TERM

netstat -lntup | grep sshd

ip addr show dev eth0

ip route

parted -s /dev/vdb mklabel gpt
parted -s /dev/vdb unit mib mkpart primary 0% 100%

mkfs.ext4 /dev/vdb1

mkdir /mnt/data
echo >> /etc/fstab
echo /dev/vdb1               /mnt/data       ext4    defaults,noatime 0 0 >> /etc/fstab
mount /mnt/data

mount -o loop,ro CentOS-7-x86_64-Everything-1511.iso /mnt/CentOS

mount.nfs nfs_server:/dir /dir
mount -tnfs4 -ominorversion=1 server_nfs_4.1:/dir

%%bash
cd ~
ls -l
date
cat py35.yml

h = !cat .bash_history 
','.join([s.split('install ')[1] for s in h if 'apt-get install' in s])

%%bash
ps --help all | grep rss

mkdir -p /not/existing/folder

cd ~
cat py35.yml | head -n 4

sed -i 's/(?<=name: )root/py352/' py35.yml
cat py35.yml | head -n 4

# http://tldp.org/LDP/abs/html/quotingvar.html
List="one two three"

for a in $List     # Splits the variable in parts at whitespace.
do
  echo "$a"
done

for a in "$List"   # Preserves whitespace in a single variable.
do #     ^     ^
  echo "$a"
  echo "${a}"
done
# one two three

a="zero zoo"

if [ $a == z* ] 
then
    echo '1'
fi

if [[ $a == z* ]]
then
    echo '2'
fi



string="1:2:3"
set -f                      # avoid globbing (expansion of *).
array=(${string//:/ })
for i in "${!array[@]}"
do
    echo "$i=>${array[i]}"
done

echo 'ps grep excluding grep pid'
RESULT_ssh_agent =`ps -aux | sed -n /[s]sh-agent/p`

if [ "${RESULT_ssh_agent:-null}" = null ]; then
	chmod 600 /home/fzinfz/.ssh/id_rsa_vultr
	eval $(ssh-agent -s)
	ssh-add /home/fzinfz/.ssh/id_rsa_vultr
else
    echo "ssh-agent running,skip adding"
fi

apt-get install git,aria2

dpkg --get-selections | grep postgres

rsync -aP  /root/_bin root@remote:/root
rsync -aP -e "ssh -p 10220" /root/data/docker-config root@remote:/root   --remove-source-files

rsync --help | grep -E '[-][ezaPrlptgoDv]\b|partial|progress|sparse'

tar -zcvf new.tar.gz directory-name

tar -ztvf my-data.tar.gz
tar -tvf my-data.tar.gz
tar -tvf my-data.tar.gz '*.py'

tar -zxvf toExtract.tar.gz

gunzip file.gz

cd ~ && wget -O - "https://www.dropbox.com/download?plat=lnx.x86_64" | tar xzf -

~/.dropbox-dist/dropboxd

./certbot-auto certonly --webroot -w  /usr/share/nginx/www/ -d example.com  -d www.example.com
/etc/letsencrypt/live/example.com/ -> /etc/letsencrypt/archive/example.com/ 
cert.pem  chain.pem  fullchain.pem  privkey.pem -> cert1.pem  chain1.pem  fullchain1.pem  privkey1.pem

apt-get install qemu-system

qemu-system-aarch64       qemu-system-m68k          qemu-system-mipsel        qemu-system-s390x         qemu-system-unicore32
qemu-system-alpha         qemu-system-microblaze    qemu-system-moxie         qemu-system-sh4           qemu-system-x86_64
qemu-system-arm           qemu-system-microblazeel  qemu-system-or32          qemu-system-sh4eb         qemu-system-x86_64-spice
qemu-system-cris          qemu-system-mips          qemu-system-ppc           qemu-system-sparc         qemu-system-xtensa
qemu-system-i386          qemu-system-mips64        qemu-system-ppc64         qemu-system-sparc64       qemu-system-xtensaeb
qemu-system-lm32          qemu-system-mips64el      qemu-system-ppcemb        qemu-system-tricore