Bruno Tinoco | IT Professional

1) Habilitando o RPMForge Repository

Os pacotes do monit e munion não estão no repositório do CentOS, por isso vamos habilitar o RPMForge

# wget http://packages.sw.be/rpmforge-release/rpmforge-release-0.3.6-1.el5.rf.i386.rpm
# rpm -Uvh rpmforge-release-0.3.6-1.el5.rf.i386.rpm

2) Instalando

# yum install monit
# chkconfig --levels 235 monit on

3) Configuração

O arquivo de configuração do monit fica em /etc/monit.conf, agora precisamos criar o arquivo de configuração para monitorar os serviços desejados, nesse exemplo vamos monitorar os serviços sshd e apache.

O acesso será feito via interface web na porta 2812, use o usuário admin e senha test.

# vi /etc/monit.d/monitrc

####################################################
# Configuração geral
set daemon 60
set logfile syslog facility log_daemon
set mailserver localhost
set mail-format { from: monit@server1.example.com }
set alert root@localhost
set httpd port 2812 and
SSL ENABLE
PEMFILE /var/certs/monit.pem
allow admin:test
# Monitorar sshd
check process sshd with pidfile /var/run/sshd.pid
start program "/etc/init.d/sshd start"
stop program "/etc/init.d/sshd stop"
if failed port 22 protocol ssh then restart
if 5 restarts within 5 cycles then timeout
####################################################

4) Configuração do certificado

A configuração do certificado se dá para uso do https, caso não queria utilizar comente as linhas SSL... e PEMFILE ... do arquivo acima e passe para etapada de executando o monit.

Agora vamos configurar o pem cert, é necessário ter instalando o OpenSSL.

# mkdir /var/certs
# vi /var/certs/monit.cnf

###################################################
# create RSA certs - Server
RANDFILE = ./openssl.rnd
[ req ]
default_bits = 1024
encrypt_key = yes
distinguished_name = req_dn
x509_extensions = cert_type
[ req_dn ]
countryName = Country Name (2 letter code)
countryName_default = MO
stateOrProvinceName = State or Province Name (full name)
stateOrProvinceName_default = Monitoria
localityName = Locality Name (eg, city)
localityName_default = Monittown
organizationName = Organization Name (eg, company)
organizationName_default = Monit Inc.
organizationalUnitName = Organizational Unit Name (eg, section)
organizationalUnitName_default = Dept. of Monitoring Technologies
commonName = Common Name (FQDN of your server)
commonName_default = server.monit.mo
emailAddress = Email Address
emailAddress_default = root@monit.mo
[ cert_type ]
nsCertType = server
#################################################################

# openssl req -new -x509 -days 365 -nodes -config ./monit.cnf -out /var/certs/monit.pem -keyout /var/certs/monit.pem
# openssl gendh 512 >> /var/certs/monit.pem
# openssl x509 -subject -dates -fingerprint -noout -in /var/certs/monit.pem
# chmod 700 /var/certs/monit.pem

5) Executando o monit

Para executar o monit use o comando abaixo:

# /etc/init.d/monit start

Para acessar a interface web use o endereço https://ip_do_servidor:2812 (login admin e senha test)

6) Observação

Para consultar maiores exemplos de monitoramento de serviços acesse http://mmonit.com/wiki/Monit/ConfigurationExamples