APM UMA Auto Attach not working for NGINX Apps

Products

• CA Application Performance Management (APM / Wily / Introscope)

Issue/Introduction

We have followed all installation steps as per documentation but AutoAttach injection for NGINX apps is not working

DX APM Agents - NGINX Agent Auto Attach 

 

Environment

• NGINX Monitor 26.3.x 

Cause

Root cause: Unsupported NGIX version.

From app-container-monitor-4xlwh\podmonitor\IntroscopeAgent.log

 

7/28/23 01:55:10 PM GMT [INFO] [IntroscopeAgent.AutoAttach.Nginx] UnixDockerEnricher - Nginx version : 1.23.3 not supported in container : 35551e8a861ae5bc10b893fd9a283ee49b79c90848718467d617fe36402b2967
7/28/23 01:55:11 PM GMT [INFO] [IntroscopeAgent.AutoAttach.Nginx] UnixDockerEnricher - Nginx App Container File Access output: [400, Command Exec error, err: "touch: cannot touch '/usr/lib/nginx/modules/nginx-probe-aa-write-access-verify.txt': Permission denied\n"]
7/28/23 01:55:11 PM GMT [INFO] [IntroscopeAgent.AutoAttach.Nginx] UnixDockerEnricher - Not Supported becuase of restricted permissions on nginx modules path location in container : 35551e8a861ae5bc10b893fd9a283ee49b79c90848718467d617fe36402b2967
7/28/23 01:55:11 PM GMT [INFO] [IntroscopeAgent.AutoAttach.Nginx] UnixDockerEnricher - Process 1 in container [namespace/cpeng-dev deploymentName/nginx-deployment pod/nginx-deployment-64d9d8cb6d-slmhq container/nginx ] Unsupported nginx . Skipping attach
7

Resolution

Below is a summary of reasons why AutoAttach NGIX could fail:

1) If the version of the NGINX in the application pod is not in the supported list {"1.10.1", "1.12.1", "1.13.8", "1.14.0", "1.14.2", "1.15.0", "1.15.8", "1.15.10", "1.15.12", "1.16.0", "1.16.1", "1.17.1", "1.18.0", "1.19.0", "1.19.1", "1.20.0"};

2) If the default standard libraries are not present in the application pod like libstdc++.so.6 which is the minimum dependent library required by the agent.

3) We only support DEBIAN, OPENSOURCE, CENTOS7 & CENTOS8, if the nginx is not one among those we will skip.

4) If the nginx is not configured with --modules-path where all the third party modules are present we will skip the autoattach process

5) If the nginx is not configured with --conf-path where the configurations of both nginx(nginx.conf) and also third party configurations are present, we will skip the autoattach process

6) If the nginx is not configured with --prefix which represents the working directory, we will skip the auoattach process

7) We require write permissions on three locations  to install nginx probe( --modules-path, --prefix, --standard-library-location). If we didn't have the necessary permissions we will skip the autoattach process.

8) We only support EXEC form of container start arguments, if the container starts with command form we will skip the autoattach process.

Additional Information

DX APM Agents - NGINX Agent Auto Attach