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Fix nginx IPv6 resolution causing backend connection failures#385

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ShaneIsrael merged 2 commits intodevelopfrom
copilot/update-nginx-to-use-ipv4
Jan 17, 2026
Merged

Fix nginx IPv6 resolution causing backend connection failures#385
ShaneIsrael merged 2 commits intodevelopfrom
copilot/update-nginx-to-use-ipv4

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Copilot AI commented Jan 17, 2026 •
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Nginx resolves localhost to IPv6 [::1] on some systems, but the backend only listens on IPv4, causing "upstream server temporarily disabled while connecting to upstream" errors.

Changes

  • Updated proxy_pass directives in /api/* and /w/* locations to use explicit IPv4 address 127.0.0.1:5000 instead of localhost:5000
  • Applied to both production (app/nginx/prod.conf) and development (app/nginx/dev.template.conf) configurations
 location ~ /api/.*$ {
-    proxy_pass              http://localhost:5000;
+    proxy_pass              http://127.0.0.1:5000;
     proxy_http_version      1.1;
Original prompt

Problem

Nginx is attempting to connect to the backend using IPv6 localhost [::1]:5000, but the backend may only be listening on IPv4, causing connection failures with the error:

upstream server temporarily disabled while connecting to upstream

Solution

Update nginx configuration files to explicitly use IPv4 localhost (127.0.0.1) instead of localhost to avoid IPv6/IPv4 resolution issues.

Files to Update

  1. app/nginx/prod.conf - Update lines 53 and 61:

    • Change proxy_pass http://localhost:5000; to proxy_pass http://127.0.0.1:5000;

  2. app/nginx/dev.template.conf - Update lines 48 and 56:

    • Change proxy_pass http://localhost:5000; to proxy_pass http://127.0.0.1:5000;

Expected Outcome

  • Nginx will reliably connect to the backend on IPv4 localhost
  • Eliminates "upstream server temporarily disabled" errors
  • API requests to /api/* and /w/* endpoints will work consistently

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Copilot AI changed the title [WIP] Update Nginx configuration to use IPv4 localhost Fix nginx IPv6 resolution causing backend connection failures Jan 17, 2026
Copilot AI requested a review from ShaneIsrael January 17, 2026 22:15
@ShaneIsrael ShaneIsrael marked this pull request as ready for review January 17, 2026 22:20
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ShaneIsrael commented Jan 17, 2026

Hoping this fixes an upstream connect error that happens all the time.

@ShaneIsrael ShaneIsrael merged commit 9dcc2ad into develop Jan 17, 2026
@ShaneIsrael ShaneIsrael deleted the copilot/update-nginx-to-use-ipv4 branch January 31, 2026 20:57
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