As a cloud engineer, mastering advanced Linux commands is crucial for efficient cloud management. Here’s a list of the top 10 commands you should know:

1. jq (JSON Processor)

Extract a specific field from a JSON file

jq '.name' data.json

Filter JSON data based on a condition

jq '.age > 25' data.json

Convert JSON to YAML

jq -r tostring data.json | yq -

2. grep (Global Regular Expression Print)

Search for a string in a file

grep "error" log.txt

Count the occurrences of a pattern

grep -c "warning" log.txt

Exclude lines that match a pattern

grep -v "info" log.txt

3. sed (Stream Editor)

Replace a string with another

sed 's/old/new/g' file.txt

Delete a specific line

sed '10d' file.txt

Insert a line before a specific pattern

sed '/pattern/i\new line' file.txt

4. awk (Pattern Scanning and Processing Language)

Print specific fields from a CSV file

awk -F, '{print $1, $3}' data.csv

Calculate the sum of a column

awk -F, '{sum+=$2} END {print sum}' data.csv

Create a histogram of values

awk '{print $1, $2 | "sort -nk2"}' data.csv

5. curl (Client for URLs)

Send an HTTP GET request


Post data to an API

curl -X POST -d '{"name": "John"}'

Download a file

curl -O

6. dig (Domain Information Groper)

Lookup DNS records for a domain


Check the MX records for a domain

dig MX

Trace the route to a server

dig +trace

7. netstat (Network Statistics)

List all active network connections

netstat -an

Show the listening ports

netstat -l

Monitor network traffic in real-time

netstat -c

8. tcpdump (Network Traffic Capture)

Capture network traffic on a specific interface

tcpdump -i eth0

Filter traffic based on a protocol

tcpdump -i eth0 'tcp port 80'

Save captured traffic to a file

tcpdump -i eth0 -w traffic.pcap

9. lsof (List Open Files)

List all open files by a specific process

lsof -p 1234

Find out which process is using a specific file

lsof /path/to/file

Close a file descriptor

lsof -i :1234 -c kill

10. ps (Process Status)

List all running processes

 ps -ef

Show detailed information about a specific process

ps -aux | grep 1234

Kill a process

 ps -ef | grep 1234 | awk '{print $2}' | xargs kill