Linux

Download

Debian

https://cdimage.debian.org/debian-cd/current/amd64/bt-dvd/

Ubuntu

http://ftp.sjtu.edu.cn/ubuntu-cd/

http://archive.ubuntu.com/ubuntu/dists/bionic-updates/main/installer-amd64/current/images/netboot/mini.iso ( Mirror only http://us.archive.ubuntu.com/ , need proxy, local DNS not working )

Debug: Console 4 or /var/log/syslog

Mirrors

http://mirrors.huaweicloud.com

Bash

https://www.gnu.org/software/bash/manual/bash.html

url=https://raw.githubusercontent.com/fzinfz/scripts/master/init.sh # alias & functions
source /dev/stdin <<< "$(curl -sS $url)"
set
-x debug
-T If set, any traps on DEBUG and RETURN are inherited
-o functrace/errtrace
shopt [-pqsu] [-o] [optname …]
-s: Enable (set) each optname.
-u: Disable (unset) each optname.
shopt -s expand_aliases # when the shell is not interactive
alias foo='...'
0: stdin; 1: stdout; 2: stderr # File descriptor
2>&1 >/dev/null
&>/dev/null
ssh-add 2>/dev/null

http://nbviewer.jupyter.org/github/fzinfz/notes/blob/master/linux.ipynb

tmux

ctrl+b x -> kill pane # /usr/share/doc/tmux/examples/screen-keys.conf
cat /usr/share/doc/tmux/examples/screen-keys.conf | grep '\bbind \w'

Init

Level

Desc

0

Halt the system.

1

Single-user mode (for special administration).

2

Local Multiuser with Networking but without network service (like NFS)

3

Full Multiuser with Networking

4

Not Used

5

Full Multiuser with Networking and X Windows(GUI)

6

Reboot.

ls -R -l /etc/rc*
ls -l /usr/lib/systemd # check `systemd` page for more
ls -l /usr/share/upstart # last release 2014; 3 years ago
ls -l /etc/init.d # SysV init
cat /etc/modules-load.d/*
apt install systemd-sysv # make link: /sbin/init -> /lib/systemd/systemd
vi ~/.bash_profile # login shells
vi ~/.bashrc # non-login shells

supervisord

http://supervisord.org/running.html

Exit code

http://tldp.org/LDP/abs/html/exitcodes.html

1 Catchall for general errors
2 Misuse of shell builtins
126 Command invoked cannot execute
127 "command not found" illegal_command Possible problem with $PATH or a typo
128+n Fatal error signal "n"
kill -9 $PPID of script $? returns 137 (128 + 9)
130 Script terminated by Control-C

Syslog Message Severities

https://tools.ietf.org/html/rfc5424#section-6.2.1

0 Emergency: system is unusable
1 Alert: action must be taken immediately
2 Critical: critical conditions
3 Error: error conditions
4 Warning: warning conditions
5 Notice: normal but significant condition
6 Informational: informational messages
7 Debug: debug-level messages

Signals

kill -l
1) SIGHUP 2) SIGINT 3) SIGQUIT 4) SIGILL 5) SIGTRAP
6) SIGABRT 7) SIGBUS 8) SIGFPE 9) SIGKILL ... 64) SIGRTMAX

kill

pkill -KILL -u {username}

top

  • 1 - Single Cpu Off (thus multiple cpus)

  • c - Command line Off (name, not cmdline)

  • i - Idle tasks On (show all tasks)

    j - Str align right Off (not right justify)

    V - Forest view On (show as branches)

    f - sort/hide columns

    (`*') could be overridden through the command-line.

Glances - A top/htop alternative - Python

https://github.com/nicolargo/glances

pip install glances[action,browser,cloud,cpuinfo,chart,docker,export,folders,gpu,ip,raid,snmp,web,wifi]

User & Permission

add user to group

sudo adduser foobar www-data
sudo usermod -a -G ftp tony

password

echo user:pwd | chpasswd

sudoers

sudo visudo
root ALL=(ALL) ALL # {terminals}=({users}) {commands}
%supergroup ALL=(ALL) NOPASSWD:ALL

chown

chown -h myuser:mygroup mysymbolic

Package Management

Redhat

Free RHEL: https://developers.redhat.com/articles/no-cost-rhel-faq/

subscription-manager register
subscription-manager attach --auto
subscription-manager repos --enable rhel-7-server-optional-rpms
subscription-manager repos --enable rhel-7-server-extras-rpms
yum install epel-release
rm -f /var/run/yum.pid <PID> && yum remove PackageKit
yum-config-manager --disable c7-media
yum --nogpgcheck localinstall xx.rpm
### EPEL
http://elrepo.org/tiki/tiki-index.php
rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-3.el7.elrepo.noarch.rpm
yum install yum-plugin-fastestmirror
yum --enablerepo=elrepo-kernel install kernel-ml

Ubuntu

Main - Canonical-supported free and open-source software. Universe - Community-maintained free and open-source software. Restricted - Proprietary drivers for devices. Multiverse - Software restricted by copyright or legal issues.

# https://mirror.tuna.tsinghua.edu.cn/help/ubuntu/
deb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ xenial main restricted universe multiverse

Debian

→ experimental → unstable(Sid) → testing → stable Unstable - repository where new & untested packages are introduced. Testing - repository with packages from unstable, if no bug are found within 10 days.

main consists of DFSG-compliant packages, which do not rely on software outside this area to operate. These are the only packages considered part of the Debian distribution. contrib packages contain DFSG-compliant software, but have dependencies not in main (possibly packaged for Debian in non-free). non-free contains software that does not comply with the DFSG.

deb http://deb.debian.org/debian/ experimental main contrib non-free
deb https://mirrors.tuna.tsinghua.edu.cn/debian stretch main contrib non-free

dpkg

dpkg --get-selections # list installed

To install .deb manually, visit linux/kernel page.

apt

apt-get install linux-base -t jessie-backports
apt-cache search linux-image | grep linux-image-4
apt install linux-image-4.10.0-9-generic linux-image-extra-4.10.0-9-generic
apt show linux-image-extra-4.10*
apt-get install --only-upgrade docker-engine
apt policy docker-ce | head -n 20
apt-get autoclean
apt list --installed
rm -r /var/lib/apt/lists/*

Grub

grub2-mkconfig -o /boot/grub2/grub.cfg
awk -F\' '/menuentry / {print $2}' /boot/grub/grub.cfg
grub2-set-default 'CentOS Linux (4.9.0-rc8-amd64) 7 (Core)'
grub2-editenv list

grub-customizer

sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

boot repair

https://sourceforge.net/p/boot-repair-cd/home/Home/ apt install linux-image-* # if vmlinuz & initrd.img missing

ubuntu

sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt-get update
sudo apt-get install -y boot-repair && boot-repair

Benchmark

http://www.brendangregg.com/Perf/linux_benchmarking_tools.png

sysbench --test=cpu --cpu-max-prime=20000 --num-threads=32 run
wget http://www.numberworld.org/y-cruncher/y-cruncher%20v0.7.1.9466-static.tar.gz
tar zxvf y-cruncher\ v0.7.1.9466-static.tar.gz

ssh redirect

ssh -L 9000:public.com:80 # visit local:9000 -> public.com:80
ssh -R 9000:localhost:3000 # visit remote:9000 -> local:3000, "GatewayPorts yes" in sshd_config
-nNT -L ... # port forwarding only, no shell

web

wget

wget -O diff_name.zip http://...

curl

curl -O http://...
curl -o diff_name.zip http://
curl -sSL $1
-f, --fail Fail silently (no output at all) on HTTP errors (H)
-s, --silent Silent mode (don't output anything)
-S, --show-error Show error. With -s, make curl show errors when they occur
-L, --location Follow redirects (H)
-o, --output FILE Write to FILE instead of stdout
-O, --remote-name Write output to a file named as the remote file

files

String replace: http://unix.stackexchange.com/questions/112023/how-can-i-replace-a-string-in-a-files

apt-get install mlocate
updatedb
locate -S
lsof -p <PID>
ls --help | grep -E '[-][tr]\b'
-r, --reverse reverse order while sorting
extension -X, size -S, time -t, version -v
-t sort by modification time, newest first
mkdir -p /not/existing/folder
cat > file <<'EOL'
EOL
ncdu --exclude='/root/data/*' /
du -hcd 2 / | more
du -a / | sort -n -r | head -n 20
ls -1 $PWD | wc -l # count files
file /bin/ps
ldd /bin/ps

find

find /home -iname tecmint.txt
find $1 -iname $2
# find . ! -readable / -writable / -executabl
# find . ! -perm -g=w
find -regextype posix-extended -regex ".*[.](py|sh)" -exec chmod +x {} \;

grep

grep --color=auto -rn -P "${regex}" ${path}
# -r, --recursive like --directories=recurse
# -n, --line-number print line number with output lines
# -P, --perl-regexp PATTERN is a Perl regular expression

compress/uncompress

gunzip file.gz
tar -czvf name-of-archive.tar.gz /path/to/directory-or-file # Compress
tar -tvf my-data.tar.gz '*.py'
tar -zxvf toExtract.tar.gz
tar -xvf {tarball.tar} {special_file} -C /target/directory
tar -cf archive.tar foo bar # Create archive.tar from files foo and bar.
tar -tvf archive.tar # List all files in archive.tar verbosely.
tar -xf archive.tar # Extract all files from archive.tar.
-t, --list list the contents of an archive
-j, --bzip2 filter the archive through bzip2
-c, --create create a new archive
-x, --extract, --get extract files from an archive
-z, --gzip, --gunzip, --ungzip filter the archive through gzip
-v, --verbose verbosely list files processed
-f, --file=ARCHIVE use archive file or device ARCHIVE
zip [options] zipfile files_list
-r recurse into directories
-x exclude the following names
-v verbose operation/print version info
-m move into zipfile (delete OS files) !!
-d delete entries in zipfile !!!
-u update: only changed or new files
xz --decompress file.xz # -dgrub

rsync

rsync -aP -e "ssh -p $3" $1 root@$2
rsync -aP /root/_bin root@remote:/root
rsync -aP -e "ssh -p 10220" /local root@remote:/dir --remove-source-files
-v, --verbose increase verbosity
-a, --archive archive mode; equals -rlptgoD (no -H,-A,-X)
--no-OPTION turn off an implied OPTION (e.g. --no-D)
-r, --recursive recurse into directories
-l, --links copy symlinks as symlinks
-p, --perms preserve permissions
-o, --owner preserve owner (super-user only)
-g, --group preserve group
-D same as --devices --specials
-t, --times preserve modification times
-S, --sparse handle sparse files efficiently
-e, --rsh=COMMAND specify the remote shell to use
--partial keep partially transferred files
--partial-dir=DIR put a partially transferred file into DIR
-z, --compress compress file data during the transfer
--progress show progress during transfer
-P same as --partial --progress

history without line numbers

history | cut -c 8-
-a append history lines from this session to the history file ~/.bash_history

time

sudo timedatectl set-ntp true
TZ='Asia/Shanghai'; export TZ

font

apt-get install xfonts-base

SELinux

getenforce
semanage port -a -t mongod_port_t -p tcp 27017

Serial Console

https://wiki.openwrt.org/doc/hardware/port.serial

cat openwrt-lantiq-ram-u-boot.asc > /dev/ttyUSB0
screen /dev/ttyUSB0 115200
picocom -b 115200 /dev/ttyUSB0

Dropbox

~/.dropbox-dist/dropboxd dropboxd will create a ~/Dropbox folder and start synchronizing it after this step! unlink: https://www.dropbox.com/account#security

Ubuntu snap

run without root

Proxy

vi /etc/environment
systemctl restart snapd

JAVA_HOME

echo export JAVA_HOME="/usr/lib/jvm/java-1.8.0-openjdk" >> /etc/profile

I18N & I10N

apt install -y locales-all
locale -a
dpkg-reconfigure locales
yum grouplist chinese-support
sudo apt-get install -y ttf-wqy-microhei #文泉驿-微米黑
sudo apt-get install -y ttf-wqy-zenhei #文泉驿-正黑
sudo apt-get install -y xfonts-wqy #文泉驿-点阵宋体

Chrome

chromium --no-sandbox # start as root

Proxy

export http_proxy=http://proxy_ip:1080
export https_proxy=http://proxy_ip:1080
sudo apt install -y proxychains
vi /etc/proxychains.conf

AD

https://wiki.samba.org/index.php/Setting_up_Samba_as_an_NT4_PDC_(Quick_Start)

cache diagnostics

https://hoytech.com/vmtouch/

git clone https://github.com/hoytech/vmtouch.git
cd vmtouch && make && sudo make install
Discovering which files your OS is caching
Telling the OS to cache or evict certain files or regions of files
Locking files into memory so the OS won't evict them
Preserving virtual memory profile when failing over servers
Keeping a "hot-standby" file-server
Plotting filesystem cache usage over time
Maintaining "soft quotas" of cache usage
Speeding up batch/cron jobs

WOL

ethtool enp1s0 | grep Wake-on
p (PHY activity)
u (unicast activity)
m (multicast activity)
b (broadcast activity)
g (magic packet activity) *
a (ARP activity)
d (disabled)

Tools - Online

http://explainshell.com/

Tools - Windows

https://www.netsarang.com/xshell_download.html https://mobaxterm.mobatek.net/features.html

CPU

getconf LONG_BIT

check_cpu_core_mapping

https://www.ibm.com/support/knowledgecenter/en/SSQPD3_2.6.0/com.ibm.wllm.doc/mappingcpustocore.html same physical/core ID =》 simultaneous multi threads (SMTs) / HT

cat /proc/cpuinfo | grep -P 'processor|physical id|core id|^$'
pip install walnut # pretty print
for c in sorted([ ( int(c['processor']), int(c['physical id']), int(c['core id']) ) for c in cpu.dict().values()]): print c

USB Persistence

https://docs.kali.org/downloading/kali-linux-live-usb-persistence http://antix.mepis.org/index.php?title=Using_liveusb_with_persistence

Video

https://askubuntu.com/questions/28033/how-to-check-the-information-of-current-installed-video-drivers

dpkg -l amdgpu-pro
glxinfo | grep direct
GALLIUM_HUD=help glxgears

OpenCL

installable client driver loader (ICD Loader) may expose multiple separate vendor installable client drivers (Vendor ICDs) for OpenCL.

sudo apt install ocl-icd-opencl-dev

zFCP

device driver that supplements the Linux SCSI stack.

Diagram

CN Mirrors

https://mirrors.tuna.tsinghua.edu.cn