linux cmd¶

awk¶

cat docs/CLI/awscli/vpc-cmd.md |awk '/^```sh title="func-.*/,/^```$/ {print}' > /tmp/$$.1

awscurl¶

export AWS_DEFAULT_REGION=us-east-2
export AMP_QUERY_ENDPOINT=https://aps-workspaces.us-east-2.amazonaws.com/workspaces/ws-xxx/api/v1/query
awscurl -X POST --region ${AWS_DEFAULT_REGION} --service aps \
"${AMP_QUERY_ENDPOINT}" -d 'query=prometheus_tsdb_head_series' \
--header 'Content-Type: application/x-www-form-urlencoded'

awscurl -X POST --region ${AWS_DEFAULT_REGION} --service aps \
"${AMP_QUERY_ENDPOINT}" -d 'query=up&time=1652382537&stats=all' \
--header 'Content-Type: application/x-www-form-urlencoded'

query=sum+%28rate+%28go_gc_duration_seconds_count%5B1m%5D%29%29&start=1652382537&end=1652384705&step=1000&stats=all

install¶

pip install git+https://github.com/okigan/awscurl

brew¶

install

sudo yum install -y git gcc make curl
git clone https://github.com/Homebrew/brew.git
sudo cp brew/bin/brew /usr/local/bin/

column¶

column -t

curl¶

curl-sample-1
badssl.com

check http return code¶

curl -sL -w '%{http_code}' -o /dev/null "https://httpbin.org/status/302"

datediff¶

http://www.fresse.org/dateutils/

git clone https://github.com/hroptatyr/dateutils.git
cd dateutils
sudo yum install -y texinfo gperf
autoreconf -i
./configure
make
sudo make install

ec2-instance-selector¶

brew tap aws/tap
brew install ec2-instance-selector

ec2-instance-selector -c 4 -m 16 -r us-east-2 -a arm64

envsubst¶

var1=string1
var2=string2

cat >$$.yaml <<-'EOF'
$var1
$var2
$var3
EOF

export var1 var2
cat $$.yaml |envsubst '$var1 $var2' > $$-new.yaml

refer envsubst

ffmpeg¶

ffmpeg

fio¶

snapshot impact with fio

firewall-cmd¶

firewall-cmd --permanent --add-port=80/tcp
firewall-cmd --reload

function¶

less or no parameters¶

在 func 中定义 local 变量，export 后在 func 外部依然无法访问

function a() {
 local var1=cccc
 echo $var1
 export var1
}

function b() {
  echo $var1
  var1=bbb
}

var1=abc

a
echo $var1

b
echo $var1

parse parameter¶

c:p: 参数 c 和 p 都需要参数
cp 参数 c 和 p 都不需要参数

function parsepara () {
    OPTIND=1
    OPTSTRING="h?v:c:p:"
    local VPC_ID=""
    local VPC_CIDR=""
    local PORTS=()
    while getopts ${OPTSTRING} opt; do
        case "${opt}" in
            v) VPC_ID=${OPTARG} ;;
            c) VPC_CIDR=${OPTARG} ;;
            p) PORTS+=("${OPTARG}") ;;
            h|\?) 
                echo "format: create-sg -v VPC_ID -c VPC_CIDR [-p PORT1] [-p PORT2]"
                echo -e "\tsample: create-sg -v vpc-xxx -p 172.31.0.0/16"
                echo -e "\tsample: create-sg -v vpc-xxx -p 0.0.0.0/0 -p 80 -p 443"
                return 0
            ;;
        esac
    done
    : ${VPC_ID:?Missing -v}
    : ${VPC_CIDR:?Missing -c}

    echo "CIDR:"${CIDR}
    echo "PORTS:"${PORTS}
    echo "PORTS[@]"${PORTS[@]}

    for i in ${PORTS[@]:--1}; do
        echo "i:"$i
    done
}

history¶

bash                        # open a new session.
unset HISTFILE              # avoid recording commands to file.
commands not recorded
.
.
exit

imagemagick¶

brew install imagemagick

ip-forward-¶

echo 'net.ipv4.ip_forward = 1
net.ipv4.conf.default.rp_filter = 0
net.ipv4.conf.default.accept_source_route = 0
' |tee -a /etc/sysctl.conf
sysctl -p

ip-public¶

cmd-my-public-ip-address

iptables-¶

MASQUERADE-¶

iptables -t nat -A POSTROUTING  -j MASQUERADE

iptables¶

yum install iptables-services -y;

# Start and configure iptables:
systemctl enable iptables;
systemctl start iptables;


# Configuration below allows allows all traffic:
# Set the default policies for each of the built-in chains to ACCEPT:
iptables -P INPUT ACCEPT;
iptables -P FORWARD ACCEPT;
iptables -P OUTPUT ACCEPT;

# Flush the nat and mangle tables, flush all chains (-F), and delete all non-default chains (-X):
iptables -t nat -F;
iptables -t mangle -F;
iptables -F;
iptables -X;

# Configure nat table to hairpin traffic back to GWLB:
iptables -t nat -A PREROUTING -p udp -s $gwlb_ip -d $instance_ip -i eth0 -j DNAT --to-destination $gwlb_ip:6081;
iptables -t nat -A POSTROUTING -p udp --dport 6081 -s $gwlb_ip -d $gwlb_ip -o eth0 -j MASQUERADE;

# Save iptables:
service iptables save;

lsblk-¶

lsblk -o name,mountpoint,label,size,uuid

network monitor¶

https://www.tecmint.com/linux-network-bandwidth-monitoring-tools/

iperf¶

https://aws.amazon.com/premiumsupport/knowledge-center/network-throughput-benchmark-linux-ec2/
server
```
sudo iperf -s
```

client

iperf -c 172.31.30.41 --parallel 40 -i 1 -t 2

openssl¶

compile

https://gist.github.com/fernandoaleman/5459173e24d59b45ae2cfc618e20fe06

encryption¶

encrypt on mac

openssl enc -aes-256-cbc -salt -in file.txt -out file.enc

decrypt on linux

openssl enc -d -aes-256-cbc -in file.enc -out file.txt -pass pass:yourpassword

parallel¶

touch 1024 files, with parallel 128, filename will test-1, test-2, etc.

time seq 1 1024 | parallel --will-cite -j 128 touch /mnt/efs/01/tutorial/touch/${directory}/test-1.4-{}

regctl¶

regctl

rsync¶

notable folder¶

rsync -narv --delete /home/ubuntu/.notable /home/ubuntu/OneDrive/CrossSync/

sync to s3¶

upload only md file to s3

–exclude 参数必须放在 –include 参数之前。

如果您需要上传多个类型文件，可以使用多个 –include 参数。

aws s3 sync ./work-notes s3://knowledge-base-quick-worknotes-1350/work-notes --delete  --exclude "*" --include "*.md"

work-notes¶

bash

export HISTSIZE=0
cd ~/Documents/
rsync -avr --delete \
    ./work-notes \
    ./SA-Baseline-50-12 \
    ./customers \
    stevenpan@10.68.69.100:/Users/stevenpan/Documents/

sed¶

file=file.md
gsed -i 's/^!\[\[\([^]]\+\)\]\]/![](\1)/' ${file}
# change 
# ![[stream-k8s-control-panel-logs-to-s3-21.png]]
# to 
# ![](stream-k8s-control-panel-logs-to-s3-21.png)

sponge & tee & redirect to same file¶

sponge reads standard input and writes it out to the specified file. Unlike a shell redirect, sponge soaks up all its input before opening the output file. This allows constructing pipelines that read from and write to the same file.

ssh¶

ssh-cmd

stress-ng¶

stress-ng --vm-bytes $(awk '_MemFree_{printf "%d\n", $2 * 0.95;}' < _proc_meminfo)k --vm-keep -m 1

container¶

apiVersion: apps/v1
kind: Deployment
metadata:
  name: cpu-stress-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: stress-ng
  template:
    metadata:
      labels:
        app: stress-ng
    spec:
      containers:

      - name: stress-ng-container
        image: polinux/stress-ng # progrium/stress
        command:
        - 'sh'
        - '-c'
        - |
          while true ; do
            echo "start stress (10 min)"
            stress-ng --cpu 2 --timeout 600
            echo "start sleep (10min)"
            sleep 600
          done
        resources:
          limits:
            cpu: "1"
          requests:
            cpu: "1"

tar¶

tar cf a.tar ./blue-green-upgrade/ --exclude=".terraform"

tcp setting - TIME_WIAT¶

net.ipv4.tcp_fin_timeout = 30
net.ipv4.ip_local_port_range = 15000 65000
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1

net.ipv4.ip_forward=1
net.ipv4.conf.all.accept_source_route = 1

tc - traffic control¶

yum install iproute-tc

doc¶

https://lartc.org/lartc.html#LARTC.COOKBOOK.FULLNAT.INTRO

scenario¶

connection-network-with-overlap-cidrs

ts¶

add timestamp at the front of every command output

yum install moreutils
ls |ts

vim¶

vim-cmd

wscat-¶

sudo apt install -y npm
npm install wscat

xfs¶

xfs-mount-¶

mount -t xfs -o nouuid /dev/nvme1n1 /mnt

get uuid¶

xfs_db -c uuid /dev/nvme1n1

xtop¶

top
htop
atop
iftop
```
iftop -t -s 10 > output
```

yum¶

yum --showduplicates list terraform
yum install terraform-1.5.7-1
yum versionlock terraform

fixed version¶

centos7centos8/9

yum install yum-plugin-versionlock

yum install python3-dnf-plugin-versionlock

ip address calc¶

yum -y install sipcalc --enablerepo=epel

brew install sipcalc