Mickey
100 lines
2.3 KiB
Markdown
100 lines
2.3 KiB
Markdown
# Proxy Reminder: Race Management Upstream Resilience
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## Problem
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`mnmsoft_proxy` currently fails hard at nginx startup if the upstream hostname
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`race-management-web` is not resolvable at config-parse time.
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Observed failure:
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```text
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host not found in upstream "race-management-web" in /etc/nginx/conf.d/default.conf
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```
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This caused the proxy container to restart in a loop whenever the
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`race-management-web` container was down or not yet attached to the shared
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Docker network.
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## What Was Already Fixed
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In `/opt/docker/apps/race-management/docker-compose.yml`:
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- `db` now uses `restart: unless-stopped`
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- `web` now uses `restart: unless-stopped`
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That reduces the chance of the backend staying down, but the proxy should still
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be made tolerant of temporary upstream absence.
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## What Needs To Be Done In Proxy
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Relevant proxy files:
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- `/opt/docker/apps/proxy/generated/default.conf`
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- possibly `/opt/docker/apps/proxy/nginx/nginx.conf`
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### Goal
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Avoid nginx resolving `race-management-web` only once at startup.
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Instead, make nginx resolve through Docker DNS at request time or with a
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short-lived resolver cache.
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### Recommended Approach
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Use Docker's internal DNS resolver and proxy through a variable.
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Typical pattern:
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```nginx
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resolver 127.0.0.11 valid=10s;
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location / {
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set $race_management_upstream http://race-management-web:8000;
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proxy_pass $race_management_upstream;
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}
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```
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### Why
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With a static upstream like:
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```nginx
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proxy_pass http://race-management-web:8000;
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```
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nginx may try to resolve the hostname during startup/config load. If the
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container is absent at that exact moment, nginx exits and the proxy restarts.
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Using `resolver 127.0.0.11` plus a variable makes nginx rely on Docker DNS more
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safely at runtime.
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## Also Clean Up
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The proxy logs also show this warning:
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```text
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the "listen ... http2" directive is deprecated
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```
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If present, replace patterns like:
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```nginx
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listen 443 ssl http2;
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```
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with the newer form appropriate for the installed nginx version.
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## After Editing
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Reload/recreate the proxy stack and verify:
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```bash
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cd /opt/docker/apps/proxy
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docker compose up -d
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docker logs --tail 100 mnmsoft_proxy
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```
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Expected result:
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- proxy stays up even if `race-management-web` is briefly unavailable during startup
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- no more `host not found in upstream "race-management-web"` fatal error
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