2c Worth of Notes

The following nuggets of knowledge costed me US2c (AUD3c) by trial and error playing with EC2 outside of the 12-month free tier.

• after modifying (creating new versions of) launch templates make sure to make it default, or be specific of the version number when launching a new EC2 instance. Otherwise, the changes will not take effect.
• It's better to copy and paste when creating User Data - I made the simple mistake of typing 'ec2_user' instead of 'ec2-user'. Also consult https://aws.amazon.com/premiumsupport/knowledge-center/execute-user-data-ec2/ to change the frequency of the execution of the user data.
• the user data is run as root.

On another note, while I was playing with the EC2 launch template, my WSL played up - the DNS setting stopped working on the Linux VMs, and WSL kept overwriting the /etc/resolv.conf file even with /etc/wsl.conf created with 

[network]
generateResolvConf = false

It turns out that WSL has to be terminated to make the wls.conf take effect; alternatively, prevent the /etc/resolv.conf from being writable by

chattr +i /etc/resolve.conf