I'm trying to build a user data file to be included on each and every AWS EC2 instance I launch.
The data should be executed on initial launch, as well as on every reboot/restart.
It is supposed to create/overwrite a .env file using params passed in the data itself, and then run a nodejs app that comes as part of the custom system image.
This is what I have so far
Content-Type: multipart/mixed; boundary="//"
MIME-Version: 1.0
--//
Content-Type: text/cloud-config; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="cloud-config.txt"
#cloud-config
cloud_final_modules:
- [scripts-user, always]
--//
Content-Type: text/x-shellscript; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename="userdata.txt"
#!/bin/bash
# Create .env file -- This works
cat << EOF > /home/ec2-user/.env
UN=XXX
PW=XXX
CID=XXX
KEY=XXX
EOF
# Start the Node.js app --Nothing happens here
screen -d -m node index.js
--//--
With a bit of additional logging, I have managed to get the machine to output the following: Node.js is not installed.
However, I don't believe this is correct, because when I SSH into the machine directly and run node --version it spits back v20.14.0.
Could this be a timing issue? Should I be calling another shell script included in the machine image directly instead to execute the file?
I have also tried to remove screen and just run node index.js directly, which no success.
Any help would be greatly appreciated!
The issue was that, by default, user data scripts execute on the machine as root user. So when I would ssh in as the default ec2-user and look for any sign the script executed, it wouldn't be there (root made it, not ec2).
To get around this, I just modified the user data script to execute relevant commands as ec2-user rather than root.
sudo -u ec2-user -i <<'EOF'
commandhere
EOF
Handled it.