安裝 LibreNMS (Docker)

安裝環境 Ubuntu 20.04 + docker compose
預計採用 image - librenms/librenms:latest
環境變數:
- TZ : Asia/Taipei
- LISTEN_IPV6 : false
- DB_HOST : 172.16.0.201
- DB_PORT : 8306
- DB_USER : librenms
- DB_PASSWORD : my_password999
Port : 8000 (http)
Volumes : /var/librenms/librenms ( config / plugins / rrd files/ logs… )

安裝與下載

建立 librenms 目錄

sudo mkdir /var/librenms/
sudo chown 1000:1000 /var/librenms/
cd /var/librenms/

下載 docker compsoe 設定檔

wget https://github.com/librenms/docker/raw/master/examples/compose/.env
wget https://github.com/librenms/docker/raw/master/examples/compose/compose.yml
wget https://github.com/librenms/docker/raw/master/examples/compose/librenms.env
wget https://github.com/librenms/docker/raw/master/examples/compose/msmtpd.env

將 .env 內的設定改成符合自己的設定 Exp.

TZ=Asia/Taipei
PUID=1000
PGID=1000

MYSQL_DATABASE=librenms
MYSQL_USER=librenms
MYSQL_PASSWORD=my_password999

將 msmtpd.env 內的設定改成符合自己的設定 Exp.

SMTP_HOST=smtp.gmail.com
SMTP_PORT=587
SMTP_TLS=on
SMTP_STARTTLS=on
SMTP_TLS_CHECKCERT=on
SMTP_AUTH=on
SMTP_USER=foo
SMTP_PASSWORD=bar
[email protected]

啟動 docker compose

docker compose up -d
docker compose logs -f

當啟動完成就可以直接輸入 http://server_ip:8000 來建立使用者

更新版本

cd /var/librenms
docker compose down
docker compose pull
docker compose up -d

命令列操作

新增監控節點 Exp. 10.0.0.197 / snmp community : mypass001

docker compose exec librenms lnms device:add 10.0.0.197 -c mypass001

手動執行掃描自動加入監控節點
1. 掃描參數設定
  1. [Global Settings]→[Discovery]→[Networks]→[Autodiscovery Networks] 加入掃描網路範圍 Exp. 10.0.0.0/24
  2. [Global Settings]→[Poller]→[SNMP]→[Communities (priority)] 加入 SNMP Agent 端的 Communities Exp. nms_ckey001 (預設 public)
2. 進行自動掃描
```
docker compose exec librenms ./snmp-scan.py
```

設定每小時自動掃描自動加入監控節點

建立 cron.txt

0 * * * * cd /var/librenms && docker compose exec librenms ./snmp-scan.py > /tmp/snmp-scan.log 2>&1

啟動 crontab
```
crontab cron.txt
crontab -l
```

驗證 Service(Nagios_Plugin) 設定參數

如果不確定參數該如何下可以正確運作, 可以先使用 cli 模式進行驗證 Exp. 檢查 Mail Server(192.168.11.241) 的 smtps / imaps / pop3s 的 SSL 憑證是否過期
```
docker compose exec -it librenms /usr/lib/monitoring-plugins/check_ssmtp -H 192.168.11.241 -p 465 -S -D 30,7 --sni mail.ichiayi.com
docker compose exec -it librenms /usr/lib/monitoring-plugins/check_spop -H 192.168.11.241 -p 995 -S -D 25,7 --sni mail.ichiayi.com
docker compose exec -it librenms /usr/lib/monitoring-plugins/check_simap -H 192.168.11.241 -p 993 -S -D 25,7 --sni mail.ichiayi.com
```
- Nagios_Plugin 存放在 librenms 容器內的 /usr/lib/monitoring-plugins/
- 如果確定可以正確運作, service 的 parameter 欄位內容就是 -H 192.168.11.241 之後的參數字串 Exp. -p 465 -S -D 30,7 –sni mail.ichiayi.com

設定告警條件(Alert Rules)

Alerts → Alert Rules → Click here to create the default alert rules!

設定告警通知(Alert Transports)

Line Notify

常見問題

已經安裝的 LibreNMS 主機設定好 snmpd , 卻無法在 LibreNMS 成功加入, 出現 SNMP v2c: No reply with community public 無法存取狀況

常見的問題是 LibreNMS 的 snmpd.conf 內所設定授權的 IP 範圍不正確, Exp. LibreNMS 主機 IP : 192.168.11.248 , 所以正常就會設定授權 IP 類似 192.168.11.248/32 Exp. snmod.conf 內設定為
```
:
com2sec mylibrenms 192.168.11.248/32 public
:
```
但是這環境已經有 docker 網路, 所以 LibreNMS 連過去主機會使用到 Docker 的網段 Exp. 172.20.0.0/16
```
localadmin@pve-librenms:~$ docker network inspect librenms_default | grep "Subnet"
                    "Subnet": "172.20.0.0/16",
```
因此需要將主機 snmpd.conf 的授權 IP 改成這 Docekr 網段 Exp.
```
:
com2sec mylibrenms 172.20.0.0/16 public
:
```
修改 snmpd.conf 後重啟 snmpd 服務就可

如果重新開機 docker network 網段會改變, 可以指定固定網段的 Docker 網路 Exp. librenms-network 修改 compose.yml

name: librenms

networks:
  librenms-network:
    name: librenms-network
    ipam:
      driver: default
      config:
        - subnet: 172.20.0.0/16
          gateway: 172.20.0.1

services:
  db:
    image: mariadb:10.5
    container_name: librenms_db
    networks:
      - librenms-network
    command:
      - "mysqld"
      - "--innodb-file-per-table=1"
      - "--lower-case-table-names=0"
      - "--character-set-server=utf8mb4"
      - "--collation-server=utf8mb4_unicode_ci"
    volumes:
      - "./db:/var/lib/mysql"
    environment:
      - "TZ=${TZ}"
      - "MYSQL_ALLOW_EMPTY_PASSWORD=yes"
      - "MYSQL_DATABASE=${MYSQL_DATABASE}"
      - "MYSQL_USER=${MYSQL_USER}"
      - "MYSQL_PASSWORD=${MYSQL_PASSWORD}"
    restart: always

  redis:
    image: redis:5.0-alpine
    container_name: librenms_redis
    networks:
      - librenms-network
    environment:
      - "TZ=${TZ}"
    restart: always

  msmtpd:
    image: crazymax/msmtpd:latest
    container_name: librenms_msmtpd
    networks:
      - librenms-network
    env_file:
      - "./msmtpd.env"
    restart: always

  librenms:
    image: librenms/librenms:latest
    container_name: librenms
    hostname: librenms
    networks:
      - librenms-network
    cap_add:
      - NET_ADMIN
      - NET_RAW
    ports:
      - target: 8000
        published: 8000
        protocol: tcp
    depends_on:
      - db
      - redis
      - msmtpd
    volumes:
      - "./librenms:/data"
    env_file:
      - "./librenms.env"
    environment:
      - "TZ=${TZ}"
      - "PUID=${PUID}"
      - "PGID=${PGID}"
      - "DB_HOST=db"
      - "DB_NAME=${MYSQL_DATABASE}"
      - "DB_USER=${MYSQL_USER}"
      - "DB_PASSWORD=${MYSQL_PASSWORD}"
      - "DB_TIMEOUT=60"
    restart: always

  dispatcher:
    image: librenms/librenms:latest
    container_name: librenms_dispatcher
    hostname: librenms-dispatcher
    networks:
      - librenms-network
    cap_add:
      - NET_ADMIN
      - NET_RAW
    depends_on:
      - librenms
      - redis
    volumes:
      - "./librenms:/data"
    env_file:
      - "./librenms.env"
    environment:
      - "TZ=${TZ}"
      - "PUID=${PUID}"
      - "PGID=${PGID}"
      - "DB_HOST=db"
      - "DB_NAME=${MYSQL_DATABASE}"
      - "DB_USER=${MYSQL_USER}"
      - "DB_PASSWORD=${MYSQL_PASSWORD}"
      - "DB_TIMEOUT=60"
      - "DISPATCHER_NODE_ID=dispatcher1"
      - "SIDECAR_DISPATCHER=1"
    restart: always

  syslogng:
    image: librenms/librenms:latest
    container_name: librenms_syslogng
    hostname: librenms-syslogng
    networks:
      - librenms-network
    cap_add:
      - NET_ADMIN
      - NET_RAW
    depends_on:
      - librenms
      - redis
    ports:
      - target: 514
        published: 514
        protocol: tcp
      - target: 514
        published: 514
        protocol: udp
    volumes:
      - "./librenms:/data"
    env_file:
      - "./librenms.env"
    environment:
      - "TZ=${TZ}"
      - "PUID=${PUID}"
      - "PGID=${PGID}"
      - "DB_HOST=db"
      - "DB_NAME=${MYSQL_DATABASE}"
      - "DB_USER=${MYSQL_USER}"
      - "DB_PASSWORD=${MYSQL_PASSWORD}"
      - "DB_TIMEOUT=60"
      - "SIDECAR_SYSLOGNG=1"
    restart: always

  snmptrapd:
    image: librenms/librenms:latest
    container_name: librenms_snmptrapd
    hostname: librenms-snmptrapd
    networks:
      - librenms-network
    cap_add:
      - NET_ADMIN
      - NET_RAW
    depends_on:
      - librenms
      - redis
    ports:
      - target: 162
        published: 162
        protocol: tcp
      - target: 162
        published: 162
        protocol: udp
    volumes:
      - "./librenms:/data"
    env_file:
      - "./librenms.env"
    environment:
      - "TZ=${TZ}"
      - "PUID=${PUID}"
      - "PGID=${PGID}"
      - "DB_HOST=db"
      - "DB_NAME=${MYSQL_DATABASE}"
      - "DB_USER=${MYSQL_USER}"
      - "DB_PASSWORD=${MYSQL_PASSWORD}"
      - "DB_TIMEOUT=60"
      - "SIDECAR_SNMPTRAPD=1"
    restart: always

第一次啟動時 docker compose logs librenms 一直出現 librenms | nginx: [emerg] socket() [::]:8000 failed (97: Address family not supported by protocol)
- 主要是該 VM 沒有啟用支援 ipv6, 因此必須將 nginx 內的設定檔關閉 Listen ipv6
  1. 修改 compose.yml 設定 LISTEN_IPV6=false
```
:
  librenms:
    image: librenms/librenms:latest
:
    environment:
:
      - "LISTEN_IPV6=false"
:
```
  2. 重新啟動
```
docker compose up -d
```

參考網址

K8s, LibreNMS