Docker PHP Configuration Checker
Analyze PHP configuration within Docker environments for production readiness.
Configuration Checks
1. php.ini Production vs Development
# BAD: Development config
RUN cp /usr/local/etc/php/php.ini-development /usr/local/etc/php/php.ini
# GOOD: Production config
RUN cp /usr/local/etc/php/php.ini-production /usr/local/etc/php/php.ini
2. OPcache Configuration
; GOOD: OPcache optimized for production
opcache.enable=1
opcache.memory_consumption=256
opcache.interned_strings_buffer=16
opcache.max_accelerated_files=20000
opcache.validate_timestamps=0
opcache.save_comments=1
3. OPcache JIT (PHP 8.4+)
opcache.jit=1255
opcache.jit_buffer_size=128M
4. PHP-FPM Pool Configuration
; BAD: Static pm wastes memory; ondemand has fork overhead
pm = static
pm.max_children = 100
; GOOD: Dynamic pm with tuned values
pm = dynamic
pm.max_children = 50
pm.start_servers = 10
pm.min_spare_servers = 5
pm.max_spare_servers = 20
pm.max_requests = 1000
5. Memory Limit
; BAD: Unlimited memory
memory_limit = -1
; GOOD: Appropriate for workload
memory_limit = 128M ; web
memory_limit = 256M ; workers
memory_limit = 512M ; batch
6. Error Reporting
; BAD: Development error display
display_errors = On
; GOOD: Production settings
display_errors = Off
display_startup_errors = Off
log_errors = On
error_log = /proc/self/fd/2
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT
7. Session Handling
; BAD: File-based sessions (not scalable)
session.save_handler = files
; GOOD: External storage
session.save_handler = redis
session.save_path = "tcp://redis:6379"
8. Upload Limits
upload_max_filesize = 20M
post_max_size = 25M
max_file_uploads = 10
9. Timezone
date.timezone = UTC
10. Realpath Cache
; GOOD: Increased for Symfony/Laravel
realpath_cache_size = 4096K
realpath_cache_ttl = 600
Grep Patterns
Grep: "php.ini-(production|development)" --glob "**/Dockerfile*"
Grep: "opcache\\." --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "^pm[. =]" --glob "**/*.conf"
Grep: "memory_limit" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "display_errors" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "session\\.save_handler" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "upload_max_filesize|post_max_size" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "date\\.timezone" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "realpath_cache" --glob "**/{Dockerfile*,*.ini,*.conf}"
Grep: "opcache\\.jit" --glob "**/{Dockerfile*,*.ini,*.conf}"
Detection Sources
- Dockerfile RUN echo — inline php.ini directives
- COPY'd php.ini — full configuration replacement
- COPY'd conf.d/*.ini — modular config files
- PHP-FPM pool config — www.conf or custom pools
- Environment variables — PHP_INI_SCAN_DIR overrides
Severity Classification
| Check | Severity | Impact |
|---|---|---|
| Using php.ini-development | Critical | Exposes errors, no OPcache |
| OPcache disabled | Critical | 3-10x slower responses |
| display_errors = On | Critical | Information disclosure |
| memory_limit = -1 | Major | OOM risk |
| validate_timestamps=1 | Major | FS checks per request |
| File-based sessions | Major | Not scalable, data loss |
| No timezone set | Minor | Inconsistent dates |
| Default upload limits | Minor | May block uploads |
| No realpath cache tuning | Minor | Extra FS lookups |
| JIT not configured | Minor | Missing perf gains |
Output Format
### PHP Config Issue: [Description]
**Severity:** Critical/Major/Minor
**Setting:** `directive = value`
**Location:** `Dockerfile:line` or `config-file:line`
**Current Value:**
```ini
directive = current_value
Recommended Value:
directive = recommended_value
Rationale: [Why this setting matters for production]
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