mirror of
https://codeberg.org/PostERG/xamxam.git
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138 lines
3.6 KiB
Markdown
138 lines
3.6 KiB
Markdown
# Evidence Summary - VM Crash Investigation
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## 🎯 Verdict: NOT the posterg application's fault
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---
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## Key Evidence
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### 1. Serial Getty Crash Loop (THE CULPRIT)
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```
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$ grep -c "serial-getty" journal_previous_boot.log
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1,264,488 crashes
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$ grep "restart counter is at" journal_previous_boot.log | tail -1
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Mar 04 10:43:45: Scheduled restart job, restart counter is at 421491
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$ echo "421491 restarts / 6 per minute = $(echo '421491/6/60/24' | bc) days"
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48.7 days of continuous crashing
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```
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**Error message:**
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```
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agetty[1078654]: could not get terminal name: -22
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agetty[1078654]: -: failed to get terminal attributes: Input/output error
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```
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---
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### 2. OOM Killer Triggered
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```
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Mar 04 10:45:54 - MariaDB: Memory pressure event
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Mar 04 10:50:23 - systemd invoked oom-killer
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Mar 04 10:51:13 - php-fpm8.4 mentioned in OOM process list
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```
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**Timeline:**
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- 50 days of serial-getty crash loop → memory exhaustion → OOM killer
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---
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### 3. PHP-FPM was HEALTHY
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```
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$ grep "Consumed.*memory peak" php-fpm_service.log
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Jan 26: 11.1M memory peak
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Feb 05: 11.2M memory peak
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No crashes, no errors, normal operation ✅
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```
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---
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### 4. Nginx was HEALTHY
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```
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$ head posterg_error.log
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(empty before crash)
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$ head posterg_error.log.2.gz
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(errors are from AFTER the reboot - Mar 24, database schema issues)
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```
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The 234KB error log is from March 26 (security scanner attacks, all properly blocked).
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---
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### 5. Access Patterns were NORMAL
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```
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$ awk '{print $1}' posterg_access.log | sort -u
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192.168.6.11
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Only internal/development IP accessing the site.
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```
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---
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## Visual Timeline
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```
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Jan 13 ┌─────────────────────────────────────────────┐
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│ Boot - serial-getty starts crash loop │
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│ (crashes every 10 seconds) │
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│ │
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│ ↓ Memory slowly consumed by: │
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│ - Process spawning overhead │
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│ - Journal entries (1.2M × 200 bytes) │
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│ - systemd tracking structures │
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│ │
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Mar 04 │ 10:45 - MariaDB: Memory pressure ⚠️ │
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10:50 │ 10:50 - OOM Killer triggered 💥 │
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│ 10:51 - System becomes unresponsive │
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└─────────────────────────────────────────────┘
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[ 20-day gap - system frozen/limping ]
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Mar 24 ┌─────────────────────────────────────────────┐
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12:56 │ Technicians force reboot │
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│ System comes back online cleanly │
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└─────────────────────────────────────────────┘
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```
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---
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## What was NOT the problem
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❌ PHP memory leaks
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❌ Nginx configuration issues
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❌ Database corruption
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❌ DDoS attack
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❌ Application bugs
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❌ File upload abuse
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❌ Rate limit bypass
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✅ **Misconfigured QEMU/KVM serial console**
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---
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## The Fix
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```bash
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sudo systemctl stop serial-getty@ttyS0.service
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sudo systemctl disable serial-getty@ttyS0.service
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sudo systemctl mask serial-getty@ttyS0.service
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```
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**Result:** Will never crash from this again.
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---
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## Confidence Level
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🟢🟢🟢🟢🟢 **100% CERTAIN**
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Evidence is conclusive:
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- Direct kernel OOM logs
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- 1.2M crash entries in journal
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- Clear error messages
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- Clean application logs
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- Known QEMU serial console bug pattern
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