5. Servidor nagios

Note

Servicio de monitorización

1dnf install nagios
2dnf install nagios-plugins-dns
3
4dnf install perl-Unicode-UTF8
5dnf install perl-utf8-all
6dnf install nagios-plugins-disk_smb
7
8pip3 install nagios-sql
9dnf install nagios-plugins-mysql

Directorio de trabajo /etc/nagios

  1. Crea nuevos directorios para nuestros componentes

    1mkdir commands
2mkdir hosts

  2. Añadir los directorios a la configuración en el fichero nagios.conf

    1cfg_dir=/etc/nagios/commands
2cfg_dir=/etc/nagios/hosts

  3. Monitorización del servidor core en el fichero hosts/core.cfg

     1define host {
 2   use                     linux-server
 3   host_name               core
 4   alias                   core
 5   address                 core
 6}
 7define service {
 8   use                     local-service
 9   host_name               core
10   service_description     WIREGUARD
11   check_command           check_core_wireguard
12}
13define service {
14   use                     local-service
15   host_name               core
16   service_description     NAGIOS
17   check_command           check_core_nagios
18}
19define service {
20   use                     local-service
21   host_name               core
22   service_description     DOCUS
23   check_command           check_core_docus
24}

  4. Monitorización del servidor database en el fichero hosts/database.cfg

     1define host {
 2   use                     linux-server
 3   host_name               database
 4   alias                   database
 5   address                 database
 6}
 7define service {
 8   use                     local-service
 9   host_name               database
10   service_description     MYSQL
11   check_command           check_mysql_custom
12}
13define service {
14   use                     local-service
15   host_name               database
16   service_description     SQLSERVER
17   check_command           check_sqlserver_custom
18}
19define service {
20   use                     local-service
21   host_name               database
22   service_description     ORACLE
23   check_command           check_oracle_custom
24}

  5. Monitorización del servidor docker en el fichero hosts/docker.cfg

     1define host {
 2   use                     linux-server
 3   host_name               docker
 4   alias                   docker
 5   address                 docker
 6}
 7define service {
 8   use                     local-service
 9   host_name               docker
10   service_description     SSH
11   check_command           check_ssh
12}
13define service {
14   use                     local-service
15   host_name               docker
16   service_description     PORTAINER
17   check_command           check_port_docker_portainer
18}
19define service {
20   use                     local-service
21   host_name               docker
22   service_description     EMBY
23   check_command           check_port_docker_emby
24}
25define service {
26   use                     local-service
27   host_name               docker
28   service_description     NEXTCLOUD
29   check_command           check_port_docker_nextcloud
30}

  6. Monitorización del servidor multiserv en el fichero hosts/multiserv.cfg

     1define host {
 2   use                     linux-server
 3   host_name               multiserv
 4   alias                   multiserv
 5   address                 samba
 6}
 7define service {
 8   use                     local-service
 9   host_name               multiserv
10   service_description     SAMBA
11   check_command           check_samba_custom
12}
13define service {
14   use                     local-service
15   host_name               multiserv
16   service_description     DNS
17   check_command           check_dns_custom
18}
19define service {
20   use                     local-service
21   host_name               multiserv
22   service_description     GIT
23   check_command           check_git_custom
24}

  7. Definición de los comandos para el servidor core en el fichero commands/core_commands.cfg

     1define command {
 2   command_name        check_core_wireguard
 3   command_line        $USER1$/check_core_wireguard
 4}
 5define command {
 6   command_name        check_core_nagios
 7   command_line        $USER1$/check_core_nagios
 8}
 9define command {
10   command_name        check_core_docus
11   command_line        $USER1$/check_core_docus
12}

  8. Definición de los comandos para el servidor database en el fichero commands/database_commands.cfg

     1define command {
 2   command_name        check_mysql_custom
 3   command_line        $USER1$/check_mysql -H database -d nagios -u nagiosadmin -p nagiosadmin
 4}
 5define command {
 6   command_name        check_sqlserver_custom
 7   command_line        $USER1$/check_mssql -H database -t sql_ping -U nagiosAdmin -P nagi0sAdmin
 8}
 9define command {
10   command_name        check_oracle_custom
11   command_line        $USER1$/check_oracle
12}

  9. Definición de los comandos para el servidor docker en el fichero commands/docker_commands.cfg

     1define command {
 2   command_name        check_port_docker_emby
 3   command_line        $USER1$/check_port -h docker -p 8096
 4}
 5define command {
 6   command_name        check_port_docker_portainer
 7   command_line        $USER1$/check_port -h docker -p 9000
 8}
 9define command {
10   command_name        check_port_docker_nextcloud
11   command_line        $USER1$/check_port -h docker -p 9002
12}

  10. Definición de los comandos para el servidor multiserv en el fichero commands/multiserv_commands.cfg

 1define command {
 2   command_name        check_dns_custom
 3   command_line        $USER1$/check_dns -H www.google.es -s dns
 4}
 5define command {
 6   command_name        check_samba_custom
 7   command_line        $USER1$/check_disk_smb -H samba -s exs01 -u diego -p blanca#11
 8}
 9define command {
10   command_name        check_git_custom
11   command_line        $USER1$/check_ssh -H git -p 22
12}

  1. Configuración de los comandos customizados

Directorio de trabajo /usr/lib64/nagios/plugins

En centos se puede convertir un fichero de shell script en un fichero ejecutable con la utilidad shc [shell compile]

  • Para checkear el estado de wireguard
    Crear el fichero check_core_wireguard.sh
    Convertirlo en un fichero binario con el comando shc -f check_core_wireguard.sh -o check_core_wireguard
    1#!/bin/bash
2python3 /usr/lib64/nagios/plugins/
    Crear el fichero check_core_wireguard.py
     1#!/usr/bin/python3
 2import os,sys
 3
 4num = os.popen('ip a | grep -E -c wg0:').read()
 5
 6if int(num) == 1:
 7   print('Interfaz de red activa')
 8   sys.exit(0)
 9else:
10   print('Interfaz de red NO ESTA activa')
11   sys.exit(2)
  • Para checkear el estado de la aplicación de nagios
    Crear los ficheros check_core_nagios.sh y check_core_nagios.py
    Convertirlo en un fichero binario con el comando shc -f check_core_nagios.sh -o check_core_nagios
    1#!/bin/bash
2python3 /usr/lib64/nagios/plugins/check_core_nagios.py

     1#!/usr/bin/python3
 2import requests, sys
 3def execute():
 4   try:
 5      response = requests.get('http://core/nagios/')
 6      print(response)
 7      code = response.status_code
 8      if code == 200:
 9            sys.exit(0)
10      elif code == 401:
11            sys.exit(0)
12      sys.exit(1)
13   except Exception as ex:
14      sys.exit(1)
15execute()
  • Para checkear el estado de la sección de documentación
    Crear los fichero check_core_docus.sh y check_core_docus.py
    Convertirlo en un fichero binario con el comando shc -f check_core_docus.sh -o check_core_docus
    1#!/bin/bash
2python3 /usr/lib64/nagios/plugins/check_core_nagios.py

     1#!/usr/bin/python3
 2import requests, sys
 3def execute():
 4   try:
 5      response = requests.get('http://core/docus/')
 6      code = response.status_code
 7      print(response)
 8      if code == 200:
 9            sys.exit(0)
10      elif code == 401:
11            sys.exit(0)
12      sys.exit(1)
13   except Exception as ex:
14      sys.exit(1)
15execute()
  • Para checkear el estado de oracle
    Crear el fichero check_oracle.sh
    Convertirlo en un fichero binario con el comando shc -f check_oracle.sh -o check_oracle
    1#!/bin/bash
2java -jar /usr/lib64/nagios/plugins/check_oracle.jar database 1521 FREE C##nagiosadmin nagiosadmin

    Crear un proyecto de maven para el fichero Main.java y compilarlo con Java 20 para crear el fichero check_oracle.jar

      1import java.sql.*;
  2import java.io.*;
  3import java.util.*;
  4
  5class Main {
  6   static int debug = 0;  // 'normal'=>0,'verbose'=>1 when -d parameter is given
  7   static String db_name = "";  // varchar(128)
  8   static String release = "";  // varchar(128)
  9   static String s_level = "";  // varchar(128)
 10   static String b_level = "";  // varchar(128)
 11   static String prdname = "";  // varchar(128)
 12   static String version = "";
 13   static String cfgfile = "";  // the returned tablespace value of space used in percent
 14   static String[] cfgdata = new String[1000];
 15   static String output = ""; // the plugin output string
 16   static String perfdata = ""; // the plugin perfdata output, returning the KB values
 17   static String dbUrl = ""; // the access URL for the database to query
 18   static String query = ""; // the SQL query to execute
 19
 20   public static void main(String args[]) {
 21      if (args.length < 5) {
 22            System.err.println("Error: Missing Arguments.");
 23            System.err.println("Usage: java check_dbversion_oracle <db-ip> <db-port> <db-instance> <db-user> <db-pwd> [-d]");
 24            System.err.println("Usage: java check_dbversion_oracle <db-ip> <db-port> <db-instance> <db-user> <db-pwd> -f configfile");
 25            System.exit(-1);
 26      }
 27      // Check if we got -d for debug
 28      if (args.length == 6 && args[5].equals("-d")) {
 29            debug = 1;
 30      }
 31
 32      // Check if we got a config file to compare against
 33      if (args.length == 7 && args[5].equals("-f")) {
 34            cfgfile = args[6];
 35            try {
 36               // Open the configuration file
 37               FileInputStream fstream = new FileInputStream(cfgfile);
 38               // Convert our input stream to a DataInputStream
 39               BufferedReader in = new BufferedReader(new InputStreamReader(fstream));
 40
 41               // Continue to read lines while there are still some left to read
 42               int counter = 0;
 43               while (in.ready()) {
 44                  String line = in.readLine();
 45                  line = line.trim();
 46                  // load config data while ignoring comment lines starting with #
 47                  if (!line.startsWith("#")) {
 48                        cfgdata[counter] = line;
 49                        counter++;
 50                  }
 51               }
 52               in.close();
 53               fstream.close();
 54            } catch (Exception e) {
 55               System.err.println("File input error");
 56            }
 57      }
 58
 59      dbUrl = "jdbc:oracle:thin:" + args[3] + "/" + args[4] + "@" + args[0] + ":" + args[1] + ":" + args[2];
 60
 61
 62      if (debug == 1) {
 63            System.out.println("DB connect: " + dbUrl);
 64      }
 65
 66      try {
 67            // use the JDBC driver
 68            Class.forName("oracle.jdbc.driver.OracleDriver");
 69      } catch (ClassNotFoundException e) {
 70            System.err.println("Error: JDBC Driver Problem.");
 71            System.err.println(e);
 72            System.exit(3);
 73      }
 74      try {
 75            // open connection to database "jdbc:oracle:thin:@destinationhost:port:dbname", "dbuser", "dbpassword"
 76            Connection connection = DriverManager.getConnection(dbUrl);
 77
 78            // build query
 79            query = "SELECT PRODUCT, VERSION FROM PRODUCT_COMPONENT_VERSION WHERE PRODUCT like '%Database%'";
 80            if (debug == 1) {
 81               System.out.println("DB query: " + query);
 82            }
 83
 84            // execute query
 85            Statement statement = connection.createStatement();
 86            ResultSet rs = statement.executeQuery(query);
 87
 88            // get database information into performance data field
 89            DatabaseMetaData dbmd = connection.getMetaData();
 90            prdname = dbmd.getDatabaseProductName();
 91
 92            while (rs.next()) {
 93               // get values from column "2"
 94               {
 95                  db_name = rs.getString(1);
 96               }
 97               {
 98                  release = rs.getString(2);
 99               }
100            }
101            if (debug == 1) {
102               System.out.format("Server Name: %20s|Product: %10s|Version: %10s\n",
103                        db_name, release);
104            }
105
106            rs.close();
107            statement.close();
108            connection.close();
109
110      } catch (java.sql.SQLException e) {
111            System.err.println(e);
112            System.exit(3); // return UNKNOWN
113      }
114
115      version = prdname + " v" + release;
116      perfdata = db_name + " v" + release;
117
118      // If we have no config file, we are in reporting mode
119      if (cfgfile.equals("")) {
120            System.out.println("Version OK: " + version + "|" + perfdata);
121            System.exit(0); // return OK
122      } else {
123            // -------------------------------------------------------------------------------
124            // We are in 'compliance' mode, we check the DB Version against the config file
125            // -------------------------------------------------------------------------------
126            int counter = 0;
127            String required = "";
128            String dbgroup = "";
129            String dbversion = "";
130            String remarks = "";
131            while (cfgdata[counter] != null) {
132               StringTokenizer st = new StringTokenizer(cfgdata[counter], "|");
133               if (st.hasMoreTokens()) {
134                  required = st.nextToken();
135               }
136               if (st.hasMoreTokens()) {
137                  dbgroup = st.nextToken();
138               }
139               if (st.hasMoreTokens()) {
140                  dbversion = st.nextToken();
141               }
142               if (st.hasMoreTokens()) {
143                  remarks = st.nextToken();
144               }
145
146               if (dbgroup.equals("oracle") && dbversion.equals(version) && required.equals("approved")) {
147                  if (!remarks.equals("")) {
148                        perfdata = remarks;
149                  }
150                  System.out.println("Version OK: " + version + "|" + perfdata);
151                  System.exit(0); // return OK
152               }
153
154               if (dbgroup.equals("oracle") && dbversion.equals(version) && required.equals("obsolete")) {
155                  if (!remarks.equals("")) {
156                        perfdata = remarks;
157                  }
158                  System.out.println("Version WARN: " + version + " obsolete" + "|" + perfdata);
159                  System.exit(1); // return WARN
160               }
161
162               if (dbgroup.equals("oracle") && dbversion.equals(version) && required.equals("med-vuln")) {
163                  if (!remarks.equals("")) {
164                        perfdata = remarks;
165                  }
166                  System.out.println("Version WARN: " + version + " vulnerable (low-medium)" + "|" + perfdata);
167                  System.exit(1); // return WARN
168               }
169
170               if (dbgroup.equals("oracle") && dbversion.equals(version) && required.equals("crit-vuln")) {
171                  if (!remarks.equals("")) {
172                        perfdata = remarks;
173                  }
174                  System.out.println("Version CRITICAL: " + version + " vulnerable (high risk)" + "|" + perfdata);
175                  System.exit(2); // return CRITICAL
176               }
177               counter++;
178            }
179            //  the OS version is not listed, we don't know exactly if its good or bad.
180            System.out.println("Version UNKNOWN: " + version + " unverified" + "|" + perfdata);
181            System.exit(3); // return UNKNOWN;
182      }
183   }
184}