Single T test

 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6813708/

Enable rsa based key authentication on Ubuntu 22

 https://askubuntu.com/questions/1409105/ubuntu-22-04-ssh-the-rsa-key-isnt-working-since-upgrading-from-20-04

ESIM activation in T-Mobile S21 Ultra

 It's been a while I am searching for a solution to activate eSIM on my T-Mobile S21 Ultra. T-Mobile or Samsung versions of instructions don't work.

Here is how to get it work.

1. Remove existing T-Mobile sim card and transfer it to a spare phone. You may not receive texts right away- so open a browser and navigate to https://messages.android.com or https://mesages.google.com. Open your android message app and hit link a device from the three dot menu. Scan the QR code and you will receive your texts in your browser.

Go back to your S21 Ultra's settings and navigate to eSIM menu. Click on add a plan and chose to transfer data from an old phone. Since my S21 is T-Mobile branded, it asked if my old phone is from T-Mobile. At this point, you need to login to your T-Mobile account. Next prompt will be for the number you want to transfer to eSIM. Choose your actual number. Follow onscreen instructions and you are all set.