Add Swap Memory to Prevent OOM Crashes During Builds

Why Builds Crash (OOM Error)

Building Next.js projects with Prisma is memory-intensive. If server RAM is full during a build, the Linux kernel kills the process. This results in a 502 Bad Gateway or exit code 255.

Signs of an OOM problem:

• Build exits with code 255
• 502 Bad Gateway after deployment
• Server becomes unresponsive during deploy

Create a 4GB Swap File

Run these commands on your server (via SSH or Coolify's Server Terminal):

COPY
# Create a 4GB swap file
fallocate -l 4G /swapfile

# Restrict permissions (security requirement)
chmod 600 /swapfile

# Format as swap space
mkswap /swapfile

# Activate the swap
swapon /swapfile

# Make swap permanent (survives reboots)
echo '/swapfile none swap sw 0 0' | tee -a /etc/fstab

Verify Swap is Active

COPY
swapon --show
free -h

Restart the Server After OOM

If the server is already unresponsive:

COPY
# SSH in and reboot
ssh root@your-server-ip
reboot

Or use Hetzner Cloud Console → Power → Restart.

After reboot (~2-3 minutes), Coolify and all containers restart automatically.

Monitor Memory During Build

COPY
# Watch memory usage live
watch -n 2 free -h