AUDIT APLIKASI — ZABBIX SERVER
================================
Tanggal audit : 2026-06-12
Sumber        : server/host.txt
Metode        : SSH langsung (root, key-based)

IP/SSH   : 10.100.1.42  |  ssh -m hmac-sha1 root@10.100.1.42 -p 22
           |  ssh -m hmac-sha1 geonet@10.100.1.42 -p 22
Hostname : ubuntudesktop
OS       : Ubuntu 22.04.1 LTS (Jammy)
Kernel   : 6.8.0-106-generic
Uptime   : ~80 hari
Resource : RAM 15 GiB (avail ~13 GiB) | Disk / 503G (7% terpakai, 33G used) | CPU 8 core
Docker   : TIDAK terinstall / tidak berjalan

Peran host: dedicated Zabbix monitoring server untuk infrastruktur Geonet.
Menjalankan Zabbix Server, Agent, Web Frontend (Apache + PHP), dan PostgreSQL
sebagai database backend. NAT Mikrotik: 117.102.73.102:10051 → 10.100.1.42:10051
(agent active checks dari luar).


A. LAYANAN ZABBIX & DEPENDENSI
------------------------------
| Layanan            | Versi paket              | Service systemd              | Port  | Status   |
|--------------------|--------------------------|------------------------------|-------|----------|
| Zabbix Server      | 6.2.6-1+ubuntu22.04      | zabbix-server.service        | 10051 | running  |
| Zabbix Agent       | 6.2.6-1+ubuntu22.04      | zabbix-agent.service         | 10050 | running  |
| Zabbix Agent 2     | —                        | zabbix-agent2.service        | —     | inactive |
| Zabbix Frontend    | 6.2.6-1+ubuntu22.04      | (via Apache2)                | 80    | running  |
| Apache2            | —                        | apache2.service              | 80    | running  |
| PostgreSQL         | 14/main                  | postgresql.service           | 5432  | running  |
| PHP                | 8.1.2                    | (mod_php / libapache2)       | —     | running  |

Paket Zabbix terinstall:
  zabbix-server-pgsql    1:6.2.6-1+ubuntu22.04
  zabbix-agent           1:6.2.6-1+ubuntu22.04
  zabbix-frontend-php    1:6.2.6-1+ubuntu22.04
  zabbix-apache-conf     1:6.2.6-1+ubuntu22.04
  zabbix-sql-scripts     1:6.2.6-1+ubuntu22.04
  zabbix-release         1:6.2-4+ubuntu22.04

Repo APT: https://repo.zabbix.com/zabbix/6.2/ubuntu jammy main

Zabbix Server uptime service: aktif sejak 2026-03-24 (~2 bulan 19 hari)
Memory zabbix-server: ~473 MiB | Tasks: ~48


B. PORT LISTENING (aktif)
-------------------------
  22    → SSH (sshd)
  80    → Apache2 (Zabbix Web UI di /zabbix/)
  5432  → PostgreSQL (0.0.0.0 dan ::)  ← terbuka semua interface
  10050 → Zabbix Agent (0.0.0.0 dan ::)
  10051 → Zabbix Server (0.0.0.0 dan ::)

  Port 443 (HTTPS) : via reverse proxy 10.100.1.24 (nginx)
  Web UI lokal     : HTTP 200 di http://localhost/zabbix/
  Web UI publik    : HTTPS 200 di https://zabbix.gisportal.id/zabbix/
                     HTTP → 301 redirect ke HTTPS


C. KONFIGURASI KUNCI
--------------------
Zabbix Server (/etc/zabbix/zabbix_server.conf):
  DBHost=localhost
  DBName=zabbix
  DBUser=zabbix
  LogFile=/var/log/zabbix/zabbix_server.log
  Timeout=4
  CacheSize=256M          (tuning 2026-06-12)
  HistoryCacheSize=128M
  ValueCacheSize=256M
  Backup config: zabbix_server.conf.bak.20260612

Zabbix Agent (/etc/zabbix/zabbix_agentd.conf):
  Server=127.0.0.1
  ServerActive=127.0.0.1
  Hostname=Zabbix server

SSH (/etc/ssh/sshd_config):
  PermitRootLogin prohibit-password  (root hanya via SSH key)
  PasswordAuthentication yes (default, dikomentari)

Firewall:
  ufw status: inactive


D. SKALA MONITORING (database zabbix)
-------------------------------------
| Metrik              | Jumlah  |
|---------------------|---------|
| Host monitored      | 59      |
| Host unmonitored    | 28      |
| Template            | 310     |
| Total hosts         | 397     |
| Items               | 25.660  |
| Triggers            | 13.596  |
| Problems aktif      | 1.020   |
| Ukuran DB total     | ~5,7 GB |

Tabel terbesar:
  history_uint   ~2,7 GB
  trends_uint    ~1,1 GB
  history        ~1,0 GB
  trends         ~402 MB
  history_text   ~213 MB
  event_tag      ~114 MB

Interface availability (tabel interface):
  unknown (0)  : 64
  available (1): 21


E. KONEKSI & AKSES SSH
----------------------
SSH key laptop (admin@DESKTOP-RRJ9G01) terdaftar di:
  /root/.ssh/authorized_keys
  /home/geonet/.ssh/authorized_keys

Login tanpa password:
  ssh -m hmac-sha1 root@10.100.1.42 -p 22     → OK (root)
  ssh -m hmac-sha1 geonet@10.100.1.42 -p 22   → OK (geonet)

Script helper: scripts/ssh-zabbix.ps1 (default user: root)


F. ERROR & PERINGATAN DI LOG
-----------------------------
File log: /var/log/zabbix/zabbix_server.log (~30 MB)

1. ValueCache penuh (perbaikan 2026-06-12):
   Dulu 988+ kali di log sebelum tuning. ValueCacheSize dinaikkan ke 256M.
   Monitor log pasca-restart untuk memastikan peringatan tidak muncul lagi.

2. Host tidak ditemukan — agent active dari 10.100.1.57:
   "cannot send list of active checks to 10.100.1.57: host [DEV16] not found"
   → Hostname agent DEV16 belum terdaftar di Zabbix.

3. SNMP timeout (intermittent) pada host Mikrotik:
   - Mikrotik-CSS-main  (mtxrHlProcessorTemperature, mtxrLTEModem, dll)
   - Mikrotik-CSS-Prod  (mtxrLTEModem, mtxrWlCMChannel, dll)

4. Preprocessing gagal:
   - LAPTOP-2N6BR1EG: net.if.status item error


G. ANALISA & CATATAN
--------------------
Kesimpulan umum: layanan inti Zabbix SEHAT dan berjalan stabil.

Selesai (2026-06-12):
  [x] ValueCacheSize tuning (256M/128M/256M) + restart zabbix-server
  [x] HTTPS Zabbix via nginx reverse proxy (zabbix.gisportal.id)
      Config: server/nginx/zabbix.gisportal.id.conf
      Deploy: /etc/nginx/conf.d/production/zabbix.conf (10.100.1.24)

Prioritas perbaikan tersisa:
  1. [OPERASIONAL] Daftarkan atau perbaiki host DEV16 (10.100.1.57) di Zabbix UI

  2. [KEAMANAN] PostgreSQL listen 0.0.0.0:5432 — batasi ke 127.0.0.1 saja
     atau aktifkan firewall (ufw) dan izinkan hanya IP internal yang perlu.

  3. [MAINTENANCE] 237 paket menunggu update; reboot diperlukan
     (kernel baru: linux-image-6.8.0-107-generic).
     /var/log = ~8,1 GB — periksa rotasi log.

  4. [VERSI] Zabbix 6.2.6 (Dec 2022) sudah melewati EOL.
     Rencanakan upgrade ke 6.4 LTS atau 7.0 LTS.

  5. [FIREWALL] ufw inactive — server bergantung pada firewall perimeter Mikrotik.


H. REVERSE PROXY (HTTPS)
------------------------
  Domain   : zabbix.gisportal.id
  Proxy    : 10.100.1.24 (nginx) → 10.100.1.42:80/zabbix
  SSL cert : /home/ssl-gisportal/gisportal.id-fullchain.pem
  Config   : /etc/nginx/conf.d/production/zabbix.conf
  Repo     : server/nginx/zabbix.gisportal.id.conf


I. ARSITEKTUR SINGKAT
---------------------
  [Browser] ──HTTPS──► [10.100.1.24 nginx] ──HTTP──► [10.100.1.42 Apache /zabbix/]

  [Zabbix Agents / NAT 10051]
           │
           ▼
  ┌─────────────────────────────────────┐
  │  10.100.1.42 (ubuntudesktop)        │
  │  ├─ Zabbix Server    :10051         │
  │  ├─ Zabbix Agent     :10050         │
  │  ├─ Apache2 + PHP    :80  (/zabbix/) │
  │  └─ PostgreSQL 14    :5432 (zabbix) │
  └─────────────────────────────────────┘


PERINTAH VERIFIKASI ULANG
-------------------------
# Status layanan Zabbix
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "systemctl status zabbix-server zabbix-agent apache2 postgresql"

# Port listening
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "ss -tlnp | grep -E '10050|10051|:80 |:5432 '"

# Versi Zabbix
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "zabbix_server -V | head -1"

# Web UI
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "curl -s -o /dev/null -w 'HTTP %{http_code}\n' http://localhost/zabbix/"

# Statistik monitoring
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "sudo -u postgres psql -d zabbix -t -A -c 'SELECT count(*) FROM hosts;'"

# Error log terbaru
ssh -m hmac-sha1 root@10.100.1.42 -p 22 "tail -20 /var/log/zabbix/zabbix_server.log"

# Via script helper (dari laptop)
.\scripts\ssh-zabbix.ps1 -Command "systemctl status zabbix-server"
