Failed to start nginx.service when running standalone_ubuntu_oss_install.sh

[shawnhankim]

Describe the bug
Failed to start nginx.service when running nginx-s3-gateway as a Systemd Service using standalone_ubuntu_oss_install.sh

To Reproduce
Steps to reproduce the behavior:

1. Create an IAM role
2. Provision an EC2 instance which associates with AWS instance profile credentials.
3. Switch user as a root via sudo su
4. Install NGINX using standalone_ubuntu_oss_install.sh
5. See the following errors:

   ▶ Starting NGINX
   Job for nginx.service failed because the control process exited with error code.
   See "systemctl status nginx.service" and "journalctl -xeu nginx.service" for details.

Expected behavior
The NGINX service should be successfully started as the following message:

▶ Creating NGINX configuration for S3 Gateway
▶ Creating directory for proxy cache
▶ Starting NGINX
root@ip-172-31-41-141:/home/ubuntu/nginx-s3-gateway-v2# ps -ef | grep nginx
root        2783       1  0 13:13 ?        00:00:00 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf
nginx       2784    2783  0 13:13 ?        00:00:00 nginx: worker process
nginx       2785    2783  0 13:13 ?        00:00:00 nginx: cache manager process
nginx       2786    2783  0 13:13 ?        00:00:00 nginx: cache loader process
root        2787    2600  0 13:13 pts/3    00:00:00 systemctl status nginx.service

A clear and concise description of what you expected to happen.

Your environment

• Version of the repo - master branch
• Version of the container used (if downloaded from Docker Hub or Github): N/A
• S3 backend implementation you are using (AWS, Ceph, NetApp StorageGrid, etc): AWS
• How you are deploying Docker/Stand-alone, etc: Stand-alone
• NGINX type: OSS
• Authentication method (IAM, IAM with Fargate, IAM with K8S, AWS Credentials, etc): IAM

Additional context

Same error occurs when the following files do not exist:

• cors.conf
• js_fetch_trusted_certificate.conf
• s3listing_location.conf
• s3_location.conf
• s3_server.conf

You could fine the error message as follows using the command of systemctl status nginx.service.

    root@ip-172-31-41-141:/home/ubuntu# systemctl status nginx.service
    × nginx.service - nginx - high performance web server
        Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
        Drop-In: /etc/systemd/system/nginx.service.d
                └─override.conf
        Active: failed (Result: exit-code) since Mon 2023-02-13 12:38:26 UTC; 35s ago
          Docs: https://nginx.org/en/docs/
        Process: 2463 ExecStartPre=/usr/local/bin/template_nginx_config.sh (code=exited, status=0/SUCCESS)
        Process: 2507 ExecStart=/usr/sbin/nginx -c /etc/nginx/nginx.conf (code=exited, status=1/FAILURE)
            CPU: 54ms

    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/js_fetch_trusted_certificat>
    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/cors.conf.template to /etc/>
    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/v4_js_vars.conf.template to>
    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/v4_headers.conf.template to>
    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/v2_headers.conf.template to>
    Feb 13 12:38:26 ip-172-31-41-141 template_nginx_config.sh[2476]: template_nginx_config.sh: Running envsubst on /etc/nginx/templates/gateway/s3_server.conf.template to >
    Feb 13 12:38:26 ip-172-31-41-141 nginx[2507]: nginx: [emerg] open() "/etc/nginx/conf.d/gateway/s3_location.conf" failed (2: No such file or directory) in /etc/nginx/co>
    Feb 13 12:38:26 ip-172-31-41-141 systemd[1]: nginx.service: Control process exited, code=exited, status=1/FAILURE
    Feb 13 12:38:26 ip-172-31-41-141 systemd[1]: nginx.service: Failed with result 'exit-code'.
    Feb 13 12:38:26 ip-172-31-41-141 systemd[1]: Failed to start nginx - high performance web server.

Sensitive Information
N/A