Map Nginx Proxy Targets

Nginx returns 502, serves a stale app, or reaches the wrong backend, and you need to see exactly where proxied requests are sent.

Command

grep -RInE '^[[:space:]]*proxy_pass[[:space:]]' fixtures/nginx/conf.d fixtures/nginx/sites-enabled

Before you run this

System impact: Read-only. Can create load on large logs, directories, filesystems, or process tables.

When not to use it: Do not assume the upstream process is running just because the config points to it. Check the backend listener and app logs next.

Expected output

Config paths and `proxy_pass` target URLs, usually hostnames, sockets, local ports, or upstream names.

System impact

Read-only, can be slow. Nothing changes. The command lists `proxy_pass` targets from config text.

Scope this to the smallest useful path or service on busy systems.

Recovery / rollback: no state is changed.

When to use it

Use when 502s, stale apps, wrong containers, or unexpected backends suggest a proxy target problem.

When not to use it

Do not assume the upstream process is running just because the config points to it. Check the backend listener and app logs next.

Watch this command run

Command transcript

This sanitized transcript shows the commands and output shape without exposing host details.

demo@lab:~$

$ grep -RInE '^[[:space:]]*proxy_pass[[:space:]]' sample-files/nginx/conf.d sample-files/nginx/sites-enabled

sample-files/nginx/conf.d/admin.conf:6:        proxy_pass http://localhost:9100;
sample-files/nginx/sites-enabled/example.conf:16:        proxy_pass http://localhost:9000/;

$ grep -RInE 'proxy_set_header[[:space:]]+Host' sample-files/nginx/conf.d sample-files/nginx/sites-enabled

sample-files/nginx/sites-enabled/example.conf:15:        proxy_set_header Host $host;

View commands shown

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