Termux in Google play store is outdated and to get the latest version of Termux you will need to get it from F-Droid. Once you successfully install Termux, update it. pkg update Upgrade it if it is outdated. pkg upgrade

Alice has a keypair, alice_private.pem and alice_public.pem Bob has a keypair, bob_private.pem and bob_public.pem Please refer to asymmetric encryption if you would like to generate key pair. Alice sends Bob alice_public.pem Hence Bob owns 1) bob_private.pem 2) bob_public.pem 3) alice_public.pem Bob sends Alice bob_public.pem Hence Alice owns 1) alice_private.pem 2) alice_public.pem 3) bob_public.pem…

I would love to use Bob and Alice for this article, unfortunately Bob’s name is too short. It needs a minimum length of 5 characters. To install GnuPG run # macOS brew install gnupg # Ubuntu sudo apt install gnupg First you’ll need to generate the key. gpg --gen-key Enter…

Converting MD5 checksum to base64 will shorten the length from 32 characters to 24 characters. Let’s say we are converting the MD5 checksum below ef2eff22b9eddfac2f242245c66cddb1 To convert hexadecimal to base64, run the command below echo ef2eff22b9eddfac2f242245c66cddb1|xxd -r -p|base64 # 7y7/Irnt36wvJCJFxmzdsQ== To convert base64 back to hexadecimal echo 7y7/Irnt36wvJCJFxmzdsQ==| base64 -d | hexdump -v -e '/1 "%02x" ' #ef2eff22b9eddfac2f242245c66cddb1

How to encrypt/decrypt files with OpenSSL. To check the version of your OpenSSL # command to check openssl version openssl version Generate private key. # generate private key based on AES128 encryption with 1024 bit openssl genrsa -aes128 -out private.pem …

I don’t format disk very often but every time when I needed to format with command line I need to google for it. It is time I add this in my blog/medium for my own reference. # To view all the disks attached # I am formatting /dev/sdb lsblk #…

How to setup and run a Prometheus Blackbox exporter in few seconds. Assuming you have Docker Desktop already installed in your Mac, if not read macOS Install Docker Desktop I previously wrote. …

Go to https://docs.docker.com/desktop/install/mac-install/ and choose whether your Mac is using Apple Silicon or Intel chip. To find out, at the top left corner of your Mac, click the apple icon and choose “About This Mac” If it is an Intel chip.

Spring Boot starter cache is able to cache REST API response but expiring the cache will be troublesome to implement. Guava cache will solve this problem. Example below is a prototype from scratch on how to implement Guava cache.