How to install Sensu Monitoring Tool on CentOS 7

To install Sensu Monitoring Tool on CentOS 7  

Sensu is an open-source scalable monitoring tool written in Ruby. It is a dynamic, ephemeral infrastructure and application monitoring and telemetry   platform used for monitoring and sending alerts and notifications of new events. Sensu uses RabbitMQ for message broking and Redis for data storing. Sensu monitors application and system services, detects those in unhealthy state and notifies via email, PagerDuty, Slack, HipChat, IRC, etc. Sensu offers Documented API, Dynamic Client Registry, Self-Service Monitoring, Secure Connectivity, Sensu Plugins, and Built-in Contact Routing. This tutorial covers the installation procedure of Sensu Monitoring tool on CentOS 7. 

Installation procedure 

To proceed with the installation procedure, download the Erlang RPM  using wget command followed by the download link. 

[root@linuxhelp ~]# wget http://packages.erlang-solutions.com/erlang-solutions-1.0-1.noarch.rpm
--2017-11-06 10:35:05--  http://packages.erlang-solutions.com/erlang-solutions-1.0-1.noarch.rpm
Resolving packages.erlang-solutions.com (packages.erlang-solutions.com)... 31.172.186.53
Connecting to packages.erlang-solutions.com (packages.erlang-solutions.com)|31.172.186.53|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1932 (1.9K) [application/x-redhat-package-manager]
Saving to: ‘ erlang-solutions-1.0-1.noarch.rpm.1’ 

100%[======================================> ] 1,932       --.-K/s   in 0s      

2017-11-06 10:35:43 (86.9 MB/s) - ‘ erlang-solutions-1.0-1.noarch.rpm.1’  saved [1932/1932]

The Erlang RPM package has been downloaded. Next install the Erlang RPM by running the following command.   

[root@linuxhelp ~]# rpm -Uvh erlang-solutions-1.0-1.noarch.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:erlang-solutions-1.0-1           ################################# [100%]
--2017-11-06 10:18:02--  http://packages.erlang-solutions.com/rpm/centos/erlang_solutions.repo
Resolving packages.erlang-solutions.com (packages.erlang-solutions.com)... 31.172.186.53
Connecting to packages.erlang-solutions.com (packages.erlang-solutions.com)|31.172.186.53|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 245
Saving to: ‘ erlang_solutions.repo’ 

100%[======================================> ] 245         --.-K/s   in 0s      

2017-11-06 10:18:03 (21.0 MB/s) - ‘ erlang_solutions.repo’  saved [245/245]

The RPM for Erlang has been installed in the target system. Now install Erlang application by running the yum install command. 

[root@linuxhelp ~]# yum install erlang
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: centos.mirror.snu.edu.in
 * epel: mirror.ehost.vn
 * extras: centos.mirror.snu.edu.in
 * updates: centos.mirror.snu.edu.in
Resolving Dependencies
-->  Running transaction check
--->  Package erlang.x86_64 0:20.1-1.el7.centos will be installed
-->  Processing Dependency: erlang-inets(x86-64) = 20.1-1.el7.centos for package: erlang-20.1-1.el7.centos.x86_64
.
.
.
.
erlang-wx.x86_64 0:20.1-1.el7.centos                                          
  erlang-xmerl.x86_64 0:20.1-1.el7.centos                                       
  mesa-libGLU.x86_64 0:9.0.0-4.el7                                              
  unixODBC.x86_64 0:2.3.1-11.el7                                                
  wxBase.x86_64 0:2.8.12-20.el7                                                 
  wxGTK.x86_64 0:2.8.12-20.el7                                                  
  wxGTK-gl.x86_64 0:2.8.12-20.el7                                               

Complete!

Download the RabbitMQ  RPM  using wget command followed by the download link. 

[root@linuxhelp ~]# wget https://www.rabbitmq.com/releases/rabbitmq-server/v3.6.1/rabbitmq-server-3.6.1-1.noarch.rpm
--2017-11-06 10:58:49--  https://www.rabbitmq.com/releases/rabbitmq-server/v3.6.1/rabbitmq-server-3.6.1-1.noarch.rpm
Resolving www.rabbitmq.com (www.rabbitmq.com)... 104.20.63.197, 104.20.62.197, 2400:cb00:2048:1::6814:3ec5, ...
Connecting to www.rabbitmq.com (www.rabbitmq.com)|104.20.63.197|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 5088884 (4.9M) [application/x-redhat-package-manager]
Saving to: ‘ rabbitmq-server-3.6.1-1.noarch.rpm’ 

100%[======================================> ] 5,088,884   1.10MB/s   in 4.5s   

2017-11-06 10:58:54 (1.09 MB/s) - ‘ rabbitmq-server-3.6.1-1.noarch.rpm’  saved [5088884/5088884]

Execute the RPM for RabbitMQ by running the following command.   

[root@linuxhelp ~]# rpm --import https://www.rabbitmq.com/rabbitmq-signing-key-public.asc

Install the  RabbitMQ application by executing the yum install command.   

[root@linuxhelp ~]# yum install rabbitmq-server-3.6.1-1.noarch.rpm
Loaded plugins: fastestmirror, langpacks
Examining rabbitmq-server-3.6.1-1.noarch.rpm: rabbitmq-server-3.6.1-1.noarch
Marking rabbitmq-server-3.6.1-1.noarch.rpm to be installed
Resolving Dependencies
-->  Running transaction check
--->  Package rabbitmq-server.noarch 0:3.6.1-1 will be installed
-->  Finished Dependency Resolution
.
.
.
.
Transaction test succeeded
Running transaction
  Installing : rabbitmq-server-3.6.1-1.noarch                               1/1 
  Verifying  : rabbitmq-server-3.6.1-1.noarch                               1/1 

Installed:
  rabbitmq-server.noarch 0:3.6.1-1                                              

Complete!

Start and enable your RabbitMQ by running the following command. 

[root@linuxhelp ~]# systemctl enable rabbitmq-server
rabbitmq-server.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig rabbitmq-server on
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit' s
   .wants/ or .requires/ directory.
2) A unit' s purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).

Start the RabbitMQ service. 

[root@linuxhelp ~]# systemctl start rabbitmq-server

Next install Redis application by executing the yum install command. 

[root@linuxhelp ~]# yum install redis
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
 * base: centos.mirror.snu.edu.in
 * epel: epel.scopesky.iq
 * extras: centos.mirror.snu.edu.in
 * updates: centos.mirror.snu.edu.in
Resolving Dependencies
-->  Running transaction check
--->  Package redis.x86_64 0:3.2.10-2.el7 will be installed
-->  Processing Dependency: libjemalloc.so.1()(64bit) for package: redis-3.2.10-2.el7.x86_64
.
.
.
Running transaction
  Installing : jemalloc-3.6.0-1.el7.x86_64                                  1/2 
  Installing : redis-3.2.10-2.el7.x86_64                                    2/2 
  Verifying  : redis-3.2.10-2.el7.x86_64                                    1/2 
  Verifying  : jemalloc-3.6.0-1.el7.x86_64                                  2/2 

Installed:
  redis.x86_64 0:3.2.10-2.el7                                                   

Dependency Installed:
  jemalloc.x86_64 0:3.6.0-1.el7      

  Add the required repository before installing Sensu tool by creating a repo file named Sensu and enter the following content in the file. Save and exit the file. 

[root@linuxhelp ~]# vim /etc/yum.repos.d/sensu.repo

[sensu]
name=sensu-main
baseurl=http://repositories.sensuapp.org/yum/el/7/x86_64/
gpgcheck=0
enabled=1

The repo file has been created successfully created. Next install the  Sensu tool by executing the following command and press y to continue with the installation process. 

[root@linuxhelp ~]# yum install sensu uchiwa -y
Loaded plugins: fastestmirror, langpacks
sensu                                                    | 2.5 kB     00:00     
sensu/primary_db                                           |  43 kB   00:00     
Loading mirror speeds from cached hostfile
 * base: centos.mirror.snu.edu.in
 * epel: mirror.ehost.vn
 * extras: centos.mirror.snu.edu.in
 * updates: centos.mirror.snu.edu.in
Resolving Dependencies
.
.
.
Installing : 1:sensu-0.26.5-2.x86_64                                      1/2 
  Installing : 1:uchiwa-0.22.0-1.x86_64                                     2/2 
  Verifying  : 1:uchiwa-0.22.0-1.x86_64                                     1/2 
  Verifying  : 1:sensu-0.26.5-2.x86_64                                      2/2 

Installed:
  sensu.x86_64 1:0.26.5-2                uchiwa.x86_64 1:0.22.0-1               

Complete!

Start and enable the Redis service. 

[root@linuxhelp ~]# systemctl start redis
[root@linuxhelp ~]# systemctl enable redis
ln -s ' /usr/lib/systemd/system/redis.service'  ' /etc/systemd/system/multi-user.target.wants/redis.service' 

Copy the .json file to the following location. 

[root@linuxhelp ~]# cp /etc/sensu/config.json.example /etc/sensu/config.json

Start and enable the following list of services. 

[root@linuxhelp ~]# systemctl start sensu-server
[root@linuxhelp ~]# systemctl start sensu-client
[root@linuxhelp ~]# systemctl start sensu-api
[root@linuxhelp ~]# systemctl start uchiwa


[root@linuxhelp ~]# systemctl enable sensu-server
sensu-server.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig sensu-server on
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit' s
   .wants/ or .requires/ directory.
2) A unit' s purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).


[root@linuxhelp ~]# systemctl enable sensu-client
sensu-client.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig sensu-client on
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit' s
   .wants/ or .requires/ directory.
2) A unit' s purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).

[root@linuxhelp ~]# systemctl enable sensu-api
sensu-api.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig sensu-api on
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit' s
   .wants/ or .requires/ directory.
2) A unit' s purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).

[root@linuxhelp ~]# systemctl enable uchiwa
uchiwa.service is not a native service, redirecting to /sbin/chkconfig.
Executing /sbin/chkconfig uchiwa on
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit' s
   .wants/ or .requires/ directory.
2) A unit' s purpose may be to act as a helper for some other unit which has
   a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
   D-Bus, udev, scripted systemctl call, ...).

Set the Firewall configuration by executing the following set of commands.   

[root@linuxhelp ~]# firewall-cmd --add-port=3000/tcp
Success

[root@linuxhelp ~]# firewall-cmd --add-port=80/tcp
Success

[root@linuxhelp ~]# firewall-cmd --add-port=443/tcp
Success

[root@linuxhelp ~]# firewall-cmd --reload
success

This concludes the installation procedure of Sensu Monitoring tool on CentOS 7.