{"id":800,"date":"2017-09-15T01:29:06","date_gmt":"2017-09-14T18:29:06","guid":{"rendered":"https:\/\/trichev.com\/blog\/?p=800"},"modified":"2017-09-15T01:30:11","modified_gmt":"2017-09-14T18:30:11","slug":"nagios-4-x-installation-on-centos-6","status":"publish","type":"post","link":"https:\/\/trichev.com\/blog\/2017\/09\/15\/nagios-4-x-installation-on-centos-6\/","title":{"rendered":"Nagios 4.x installation on CentOS 6"},"content":{"rendered":"

Installation and Configuration<\/strong><\/p>\n

yum install httpd php gcc glibc glibc-common gd gd-devel -y
\nuseradd nagios
\ngroupadd nagcmd
\nusermod -a -G nagcmd nagios
\nusermod -a -G nagcmd apache<\/code><\/p>\n

yum install -y rpm-build doxygen gperf bind-utils mysql-devel net-snmp-utils openssl-devel postgresql-devel samba-client<\/code><\/p>\n

mkdir -p ~\/rpmbuild\/{BUILD,BUILDROOT,RPMS,SOURCES,SPECS,SRPMS}<\/code><\/p>\n

mkdir -p ~\/src && cd ~\/src<\/code><\/p>\n

wget http:\/\/sourceforge.net\/projects\/nagios\/files\/nagios-4.x\/nagios-4.0.8\/nagios-4.0.8.tar.gz
\nwget http:\/\/www.nagios-plugins.org\/download\/nagios-plugins-2.0.3.tar.gz
\ntar zxvf nagios-4.0.8.tar.gz
\ntar zxvf nagios-plugins-2.0.3.tar.gz<\/code><\/p>\n

mv nagios-4.0.8.tar.gz ~\/rpmbuild\/SOURCES
\nmv nagios-plugins-2.0.3.tar.gz ~\/rpmbuild\/SOURCES\/<\/code><\/p>\n

cd ~\/src\/nagios-4.0.8 && ls | grep *.spec<\/code><\/p>\n

vi nagios.spec
\n#add
\n%define _libdir %{_exec_prefix}\/lib<\/code><\/p>\n

rpmbuild -ba nagios.spec<\/code><\/p>\n

cd ~\/src\/nagios-plugins-2.0.3 && ls | grep *.spec<\/code><\/p>\n

vi nagios-plugins.spec<\/code>
\ncomment %config(missingok,noreplace) %{_sysconfdir}\/command.cfg<\/code><\/p>\n

update %doc ChangeLog command.cfg<\/code>
\nto
\n%doc ChangeLog<\/code><\/p>\n

rpmbuild -ba nagios-plugins.spec<\/code><\/p>\n

yum install -y nagios-4.0.8-2.el6.x86_64.rpm nagios-contrib-4.0.8-2.el6.x86_64.rpm nagios-devel-4.0.8-2.el6.x86_64.rpm nagios-plugins-2.0.3-1.x86_64.rpm<\/code><\/p>\n

vi \/etc\/nagios\/objects\/contacts.cfg<\/code><\/p>\n

mail user@domain.com;<\/code><\/p>\n

vi \/etc\/httpd\/conf.d\/nagios.conf<\/code>
\n
\n#Order allow,deny
\n#Allow from all
\nOrder deny,allow
\nDeny from all
\nAllow from 127.0.0.1 192.168.1.0\/24 192.168.2.0\/24<\/code><\/p>\n

htpasswd -s -c \/etc\/nagios\/htpasswd.users nagiosadmin<\/code><\/p>\n

service httpd start
\nservice nagios start
\nchkconfig httpd on
\nchkconfig nagios on<\/code><\/p>\n

\/usr\/bin\/nagios -v \/etc\/nagios\/nagios.cfg<\/code><\/p>\n

yum install policycoreutils-python<\/code><\/p>\n

If SELinux is enforcing then add this line.
\nsemanage fcontext -a -t httpd_sys_content_t \/usr\/share\/nagios\/<\/code><\/p>\n

yum install mod_ssl<\/code><\/p>\n

service httpd restart<\/code><\/p>\n

vi \/etc\/nagios\/nagios.cfg
\ncfg_dir=\/etc\/nagios\/servers<\/code><\/p>\n

NRPE Server installation\/configuration<\/strong><\/p>\n

yum install nagios-plugins-nrpe -y <\/code><\/p>\n

ln -s \/usr\/lib64\/nagios\/plugins\/check_nrpe \/usr\/lib\/nagios\/plugins\/check_nrpe<\/code>
\n
\nvi \/etc\/nagios\/objects\/commands.cfg
\ndefine command{
\ncommand_name check_nrpe
\ncommand_line \/usr\/lib\/nagios\/plugins\/check_nrpe -H '$HOSTADDRESS$' -c '$ARG1$'
\n}<\/code><\/p>\n

NRPE Client installation\/configuration<\/strong><\/p>\n

#nrpe is a part of EPEL repo
\nyum install nrpe openssl -y
\nyum install nagios-plugins-2.0.3-1.x86_64.rpm -y<\/code><\/p>\n

vi \/etc\/nagios\/nrpe.cfg
\n#nagios server
\nallowed_hosts=127.0.0.1,192.168.1.60<\/code><\/p>\n

service nrpe restart
\nchkconfig nrpe on<\/code><\/p>\n

NRPE Server\/Client configuration for PostgreSQL monitoring<\/strong><\/p>\n

server:
\nvi \/etc\/nagios\/servers\/dev-servers-services.cfg
\ndefine service {
\nuse generic-service
\nhost_name srvwiki01v
\nservice_description Mediawiki PostgreSQLD Connection
\ncheck_command check_nrpe!check_pgsql
\n}<\/code><\/p>\n

client:
\nvi \/etc\/nagios\/nrpe.cfg
\ncommand[check_pgsql]=\/usr\/lib\/nagios\/plugins\/check_pgsql -H 192.168.1.62 -l nagios<\/code><\/p>\n

service nrpe restart<\/code><\/p>\n

Testing from server:
\n\/usr\/lib\/nagios\/plugins\/check_nrpe -H 192.168.1.62 -c check_pgsql<\/code>
\nCRITICAL – no connection to ‘wikidb’ (FATAL: no pg_hba.conf entry for host “192.168.1.62”, user “nagios”, database “wikidb”, SSL off). *
\n* or default DB – “template1”<\/p>\n

Let’s configure ACL:
\nvi \/var\/lib\/pgsql\/data\/pg_hba.conf
\nhost template1 nagios 192.168.1.62\/32 trust<\/code><\/p>\n

Create nagios user in postgresql:<\/p>\n

su postgres -c bash\r\n$createuser\r\nEnter name of role to add: nagios\r\nShall the new role be a superuser? (y\/n) n\r\nShall the new role be allowed to create databases? (y\/n) n\r\nShall the new role be allowed to create more new roles? (y\/n) n\r\n$exit<\/code><\/pre>\n
Testing connection from nagios server:<\/p>\n
[root@srvmon01v ~]# \/usr\/lib\/nagios\/plugins\/check_nrpe -H 192.168.1.62 -c check_pgsql\r\nOK - database wikidb (0.003504 sec.)|time=0.003504s;2.000000;8.000000;0.000000<\/code><\/pre>\n
SNMP Client configuration<\/strong><\/p>\n
CentOS6
\nyum install -y net-snmp<\/code><\/p>\n
or<\/p>\n
CentOS5
\nyum install -y net-snmp net-snmp-utils net-snmp-devel<\/code><\/p>\n
or<\/p>\n
SLES11
\nzypper install net-snmp<\/code><\/p>\n
service snmpd stop<\/code><\/p>\n
mv \/etc\/snmp\/snmpd.conf \/etc\/snmp\/snmpd.conf_bak<\/code><\/p>\n
#Creating snmpv3 user
\nCentOS6
\nnet-snmp-create-v3-user -ro -A snmpv3authPass -a SHA -X snmpv3encPass -x AES snmpv3user<\/code><\/p>\n
or<\/p>\n
CentOS5
\nnet-snmp-config --create-snmpv3-user -ro -A snmpv3authPass -a SHA -X snmpv3encPass -x AES snmpv3user<\/code><\/p>\n
chkconfig snmpd on
\nservice snmpd start<\/code><\/p>\n
snmpwalk -u snmpv3user -A snmpv3authPass -a SHA -X snmpv3encPass -x AES -l authPriv 127.0.0.1 -v3<\/code><\/p>\n
#Ubuntu 9
\nremove \/usr\/share\/snmp\/snmp.conf and \/var\/lib\/snmp\/snmpd.conf
\nnet-snmp-config --create-snmpv3-user -ro -A snmpv3authPass -a SHA -X snmpv3encPass -x AES snmpv3user
\nstart snmpd<\/code><\/p>\n
vi \/etc\/sysconfig\/iptables<\/code>
\nCentOS6
\n-A INPUT -m state --state NEW -m udp -p udp -s 192.168.1.60 --dport 161 -j ACCEPT<\/code><\/p>\n
or<\/p>\n
CentOS5
\n-A RH-Firewall-1-INPUT -m state --state NEW -m udp -p udp -s 192.168.1.60 --dport 161 -j ACCEPT<\/code><\/p>\n
service iptables restart<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"
Installation and Configuration yum install httpd php gcc glibc glibc-common gd gd-devel -y useradd nagios groupadd nagcmd usermod -a -G nagcmd nagios usermod -a -G nagcmd apache yum install -y rpm-build doxygen gperf bind-utils mysql-devel net-snmp-utils openssl-devel postgresql-devel samba-client mkdir -p ~\/rpmbuild\/{BUILD,BUILDROOT,RPMS,SOURCES,SPECS,SRPMS} mkdir -p ~\/src && cd ~\/src wget http:\/\/sourceforge.net\/projects\/nagios\/files\/nagios-4.x\/nagios-4.0.8\/nagios-4.0.8.tar.gz wget http:\/\/www.nagios-plugins.org\/download\/nagios-plugins-2.0.3.tar.gz tar zxvf nagios-4.0.8.tar.gz […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[231],"tags":[212,32,244,14,11],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/posts\/800"}],"collection":[{"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/comments?post=800"}],"version-history":[{"count":2,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/posts\/800\/revisions"}],"predecessor-version":[{"id":802,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/posts\/800\/revisions\/802"}],"wp:attachment":[{"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/media?parent=800"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/categories?post=800"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/trichev.com\/blog\/wp-json\/wp\/v2\/tags?post=800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}