====== 加裝 Nagios Plugin 增加監控能力 ======

  * 返回 [[tech:librenms]]

===== 安裝語法 =====
  * CentOS 7 <cli>
yum install nagios-plugins-all
</cli>
  * Ubuntu 20.04 <cli>
sudo apt install nagios-plugins
</cli>

===== 進行設定 =====
==== CentOS 7 ====
  * 更改設定檔 <code sh>vi /opt/librenms/config.php</code><file>
:
# nagios-plugins-all
$config['show_services']           = 1;
$config['nagios_plugins']   = "/usr/lib64/nagios/plugins";
</file><code sh>
chmod +x /usr/lib64/nagios/plugins/*
</code>

==== Ubuntu 20.04 ====
  * 更改設定檔 <code sh>vi /opt/librenms/config.php</code><file>
:
# nagios-plugins
$config['show_services']           = 1;
$config['nagios_plugins']   = "/usr/lib/nagios/plugins";
</file><code sh>
chmod +x /usr/lib/nagios/plugins/*
</code>

===== 共同設定 =====
  * 設定定時起動 services-wrapper.py <code sh>vi /etc/cron.d/librenms</code><file>
:
*/5  *    * * *   librenms    /opt/librenms/services-wrapper.py 1

# Daily maintenance script. DO NOT DISABLE!
:
</file>
  * CentOS 7<code sh>
service crond restart
</code>
  * Ubuntu 20.04 <cli>
systemctl restart cron 
</cli>
  * 可以透過 Add Service 增加設定檢查 SSL 憑證到期日, mail 服務運作是否正常...等等的設定
    * {{:tech:2019010801.png}}
    * {{:tech:2019010802.png}}
    * {{:tech:2019010803.png}}
    * {{:tech:2019010804.png}}

<note>
  * 如果要研究所有 plugin 的語法, 可以直接到 /usr/lib64/nagios/plugins 目錄內下命令測試 Exp. ssmtp -> check_ssmtp <code sh>
cd /usr/lib64/nagios/plugins/
./check_ssmtp --help
</code>
++++看結果|<file>
[root@ct-librenms plugins]# ./check_ssmtp --help
check_ssmtp v2.2.1.git (nagios-plugins 2.2.1)
Copyright (c) 1999 Ethan Galstad <nagios@nagios.org>
Copyright (c) 1999-2014 Nagios Plugin Development Team
        <devel@nagios-plugins.org>

This plugin tests SSMTP connections with the specified host (or unix socket).

Usage:
check_ssmtp -H host -p port [-w <warning time>] [-c <critical time>] [-s <send string>]
[-e <expect string>] [-q <quit string>][-m <maximum bytes>] [-d <delay>]
[-t <timeout seconds>] [-r <refuse state>] [-M <mismatch state>] [-v] [-4|-6] [-j]
[-D <warn days cert expire>[,<crit days cert expire>]] [-S <use SSL>] [-E]
[-N <server name indication>]

Options:
 -h, --help
    Print detailed help screen
 -V, --version
    Print version information
 --extra-opts=[section][@file]
    Read options from an ini file. See
    https://www.nagios-plugins.org/doc/extra-opts.html
    for usage and examples.
 -H, --hostname=ADDRESS
    Host name, IP Address, or unix socket (must be an absolute path)
 -p, --port=INTEGER
    Port number (default: none)
 -4, --use-ipv4
    Use IPv4 connection
 -6, --use-ipv6
    Use IPv6 connection
 -E, --escape
    Can use \n, \r, \t or \\ in send or quit string. Must come before send or quit option
    Default: nothing added to send, \r\n added to end of quit
 -s, --send=STRING
    String to send to the server
 -e, --expect=STRING
    String to expect in server response (may be repeated)
 -A, --all
    All expect strings need to occur in server response. Default is any
 -q, --quit=STRING
    String to send server to initiate a clean close of the connection
 -r, --refuse=ok|warn|crit
    Accept TCP refusals with states ok, warn, crit (default: crit)
 -M, --mismatch=ok|warn|crit
    Accept expected string mismatches with states ok, warn, crit (default: warn)
 -j, --jail
    Hide output from TCP socket
 -m, --maxbytes=INTEGER
    Close connection once more than this number of bytes are received
 -d, --delay=INTEGER
    Seconds to wait between sending string and polling for response
 -D, --certificate=INTEGER[,INTEGER]
    Minimum number of days a certificate has to be valid.
    1st is #days for warning, 2nd is critical (if not specified - 0).
 -S, --ssl
    Use SSL for the connection.
 -w, --warning=DOUBLE
    Response time to result in warning status (seconds)
 -c, --critical=DOUBLE
    Response time to result in critical status (seconds)
 -t, --timeout=INTEGER:<timeout state>
    Seconds before connection times out (default: 10)
    Optional ":<timeout state>" can be a state integer (0,1,2,3) or a state STRING
 -v, --verbose
    Show details for command-line debugging (Nagios may truncate output)

Send email to help@nagios-plugins.org if you have questions regarding use
of this software. To submit patches or suggest improvements, send email to
devel@nagios-plugins.org
</file>++++
</note>

===== 檢查網站 SSL 憑證到期日 =====
  * 因為網站大量使用 Web Virtual Host 方式設定, 但檢查 SSL 憑證到期日都只會回應預設的網址憑證到期日.. Exp. www.ichiayi.com 與 svn.ichiayi.com <file>
./check_http -H www.ichiayi.com --ssl -C 30,10
SSL OK - Certificate 'www.ichiayi.com' will expire in 79 days on 2019-06-14 23:34 +0800/CST.

./check_http -H svn.ichiayi.com --ssl -C 30,10
SSL OK - Certificate 'www.ichiayi.com' will expire in 79 days on 2019-06-14 23:34 +0800/CST.
</file> 所以看到 svn.ichiayi.com 回應出來的結果會出現 www.ichiayi.com , 這問題可以**增加 --sni 參數**來解決<file>
./check_http -H www.ichiayi.com --ssl --sni -C 30,10
SSL OK - Certificate 'www.ichiayi.com' will expire in 79 days on 2019-06-14 23:34 +0800/CST.

./check_http -H svn.ichiayi.com --ssl --sni -C 30,10
SSL WARNING - Certificate 'svn.ichiayi.com' expires in 29 day(s) (2019-04-26 15:26 +0800/CST).
</file>

===== 檢查網址回應效率與關鍵字 =====
  * 檢查特定網址的回應效率與正確性 .. Exp. https://172.16.1.32/erptools/Tracing_material.php
    * 參考網址 - https://raymii.org/s/tutorials/Service_checks_in_LibreNMS_nagios_plugins.html
    * {{:tech:2019090301.png}}
    * 參數說明 
      * -E : 額外的效能資料
      * -I : 指定特定的 IP (Exp. 網站內部外部 IP 不同)
      * -S : 使用 SSL 加密協定 (https) **如有出現 Cannot make SSL connection 錯誤訊息可加上 --sni** Exp. <cli>--sni -S</cli>
      * -p 443 : 使用連線埠 443
      * -u : 要進行效能檢核的網址
      * -s : 網頁內容必須出現的關鍵字串 Exp. Jonathan
    * 檢核的結果可能類似以下的訊息 : <code>
HTTP OK: HTTP/1.1 200 OK - 1073685 bytes in 0.536 second response time
</code>

===== 參考網址 =====
  * 參考相關參數的意義 - https://www.monitoring-plugins.org/doc/man/index.html
      * https://www.monitoring-plugins.org/doc/man/check_http.html
      * https://www.monitoring-plugins.org/doc/man/check_ping.html

{{tag>librenms_agent nagios}}