Author Archives: vicki

The du command is very useful when you are looking at disk space usage. Here are some of the most commonly used parameters: -h human-readable Displays sizes in human-readable format, using units such as KB, MB, GB, etc-a, –all Lists … Continue reading →

#Run iostat to get the average cpu usage every 10 seconds for 10 times:iostat -x 10 10 >> /home/<user>/iostat.out.$(date +”%Y-%m-%d”) #Run dstat to get cpu stats for cpus 1, 3 and the total:dstat -C 0,3,total

top and htop are free CLI process viewers. They list the top resource using processes being run.The information includes: top options:–a : Sort by memory usage This switch makes top to sort the processes by allocated memory–d : Delay time update interval as: -d ss.tt (seconds.tenths)–p : Monitor PIDs as: -pN1 … Continue reading →

Watch disk usage updating every 3 seconds:watch -d -n 3 ‘df -h’

Sed strings make VIM very powerful. You can use them to do many things. The changes will not be written to the file until you save the file, so you are safe to experiment a bit. To delete lines 4-12: … Continue reading →

Tar and encrypt: tar cz <dir>/ | openssl enc -aes-256-cbc -pbkdf2 -iter 10000 -e > out.tar.gz.enc Decrypt:openssl enc -aes-256-cbc -d -in out.tar.gz.enc | tar xz

Since RedHat/Ubuntu/Debian’s /proc/cpuinfo has a separate entry for each CPU core, you can use this command to count them:cat /proc/cpuinfo | grep processor | wc -l Or do it with the following Python script:—-!/usr/bin/env python3 import osimport psutil l1, l2, l3 = … Continue reading →

To convert a UTF-8 encoded file to UTF-16, you can use iconv on the command line: iconv -f utf-8 -t utf-16 oldfile > newfile

To connect to MySQL through a tunnel Open a tunnel on your local machine listening on localhost:3307 and forwarding everything to the mysqlserver server on port 3306, and doing it all via the ssh service on the gateway machine. ssh … Continue reading →