nextjs - 💡(How to fix) Fix /_next/image returns 504 / infinite loading for external images when using bun install on Linux server with PM2 [1 comments, 2 participants]

Link to the code that reproduces this issue

https://nextjs.org/docs/app/getting-started/images

To Reproduce

1. Build project using bun install && bun run build Ubuntu 24 Linux server
2. Run bun install --production on the server (without rebuilding sharp)
3. Start with PM2 — pm2 start ecosystem.config.js
4. Open any page with <Image /> component pointing to external URL (S3)
5. Observe infinite loading → 504

Current vs. Expected behavior

Current behavior

After upgrading from 16.1.6 → 16.2.0, all <Image /> components hang indefinitely on production server (Ubuntu 24, PM2, deployed with bun) and eventually return 504. This affects both external images (AWS S3 via remotePatterns) and local static assets. The /_next/image optimization endpoint never responds.

Server logs:

⨯ The requested resource isn't a valid image for https://....s3.amazonaws.com/user-media/....png received null ⨯ Error: The router state header was sent but could not be parsed.

Expected behavior

Images load correctly, same as in 16.1.6. If sharp is unavailable or incompatible at runtime, Next.js should fail fast with a clear error — not silently hang the /_next/image handler until timeout.

Notes

Works perfectly in local development on both versions

Adding images: { unoptimized: true } to next.config.js immediately fixes the issue, confirming the problem is isolated to the image optimization pipeline

Suspected cause: sharp native binary compiled on the build machine (macOS/Windows) is not recompiled for Linux x64 when running bun install --production on the server. 16.2.0 appears to handle this failure differently than 16.1.6

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #71-Ubuntu SMP PREEMPT_DYNAMIC Tue Jul 22 16:52:38 UTC 2025
  Available memory (MB): 3820
  Available CPU cores: 3
Binaries:
  Node: 24.12.0
  npm: 11.6.2
  Yarn: N/A
  pnpm: N/A
Relevant Packages:
  next: 16.2.0 // Latest available version is detected (16.2.0).
  eslint-config-next: N/A
  react: 19.2.4
  react-dom: 19.2.4
  typescript: 5.9.3
Next.js Config:
  output: N/A

Which area(s) are affected? (Select all that apply)

Image (next/image)

Which stage(s) are affected? (Select all that apply)

Other (Deployed)

Additional context

Deploying to: Self-hosted Ubuntu 24 LTS VPS, managed with PM2 (cluster mode)

Reproducible: Production only. Local development (macOS) works fine on both 16.1.6 and 16.2.0

Build & deploy flow:

• bun install && bun run build on the server (same machine)
• Built artifacts synced via rsync (excluding node_modules/)
• bun install --production in production directory
• pm2 reload

sharp is the likely culprit — after running npm install --platform=linux --arch=x64 --legacy-peer-deps sharp manually on the server and removing unoptimized: true, images still failed. The bun package manager appears to not correctly handle sharp's native binary compilation for the target platform regardless of flags.

Browser: Reproduced in all browsers (Chrome, Firefox, Safari) — rules out browser-specific issue

next.config.js images config:

images: {
  remotePatterns: [
    {
      protocol: "https",
      hostname: "*.s3.eu-north-1.amazonaws.com",
      pathname: "/**",
    },
  ],
}

Workaround in use: images: { unoptimized: true } — functional but loses all image optimization benefits