user data on EC2 not working with CDK

Question

Hi team,

I created an ec2 instance with CDK and added used data on it :

```
   const userData = readFileSync("lib/my-script.sh", "utf8");
    instance.addUserData(userData);
    instance.applyRemovalPolicy(RemovalPolicy.DESTROY);
```

my-script.sh :

```
#! /bin/bash
sudo su
yum -y update
# adding MYSQL client to connect to RDS(MYSQL) instance.
sudo yum install mysql
```
but when i connect to my ec2 instance via the session manager tab and do MySQL command I have this error :

`sh: mysql: command not found`

looks like the user data script was not run.

I'm I missing something?
how can I know if the user data script was successfully run on the ec2 instance?

found this on : `/var/log/cloud-init-output.log`

```
Sep 15 00:17:50 cloud-init[xxxx]: util.py[WARNING]: Failed running /var/lib/cloud/instance/scripts/part-001 [1]
Sep 15 00:17:50 cloud-init[xxxx]: cc_scripts_user.py[WARNING]: Failed to run module scripts-user (scripts in /var/lib/cloud/instance/scripts)
Sep 15 00:17:50 cloud-init[xxxx]: util.py[WARNING]: Running module scripts-user () failed
ci-info: no authorized ssh keys fingerprints found for user ec2-user.
```

thank you!

Jess · Accepted Answer

removed  "sudo" from the script as User Data scripts are run as root user as per this answer:

https://stackoverflow.com/questions/67740072/user-data-not-running-command-in-mysql

https://stackoverflow.com/questions/41603517/installing-mysql-client-on-ec2-via-cloudformation

also noticed that ec2 add `#!/bin/bash` on top of the script even if it already exists

my final script :

```
yum -y update
# adding MYSQL client to connect to RDS(MYSQL) instance.
yum -y install mysql
```

Brettski-AWS · Answer

I think you need to do `sudo yum install mysql -y` so that the `yum` utility doesn't try and prompt the user.

user data on EC2 not working with CDK

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