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What are we going to do ?
We are going to turn our Raspberry Pi into a network monitoring center, to have control over our network services. To do this we are going to use the Nagios program, which is a software that provides great versatility to query virtually any parameter of interest of a system, and generates alerts, which can be received by the corresponding managers via email and SMS messages, when these parameters exceed the margins defined by the network administrator.
SOURCE: https://docs.nemslinux.com/en/latest/index.html
NEMS is a free and open-source computer-software application that monitors systems, networks and infrastructure
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What we need ?
– Raspberry Pi model 3 or higher
– Minimum 16GB Micro SD card
– Micro SD card reader
– HDMI cable
– Raspberry Power
– Ethernet cable
Installation
On the Nems website we have all the information necessary for the installation, we can find the iso file to load it on the raspberry.
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We connect the Micro SD card reader to the laptop
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With the Balenaetcher program we flash the SD and insert it into the Raspberry
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Connect the power, the ethernet cable and the HDMI
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Setting
We are going to configure the Nems, to do this we press Ctrl + alt + Z + F2 to start and enter the following command
sudo nems-init
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Once the program has started we have to make different configurations, we continue the process until everything is completed
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NEMS Administrator User
Default Username and Password
The default username on a fresh installation of NEMS Linux is nemsadmin. This is used to sign-in to your NEMS Server (over SSH or keyboard connected to your NEMS Server) only until you run nems-init.
Username: nemsadmin
Password: nemsadmin
Post-Initialization
Once your nems-init process is complete, you will need to instead sign-in as your newly created account (which you specify during nems-init).
When you initialize NEMS, you will provide a password for the NEMS web interfaces. This username/password will be what you use to access NEMS features (eg., nCONF, Nagios Core, NagVis, Check_MK, Samba, Webmin, SSH, etc.).
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Once the account is created and configured, we go to the following link https://nems.local , where we can explore the different functions of the NEMS system, add a host, monitor and configure our devices, add humidity and temperature sensors…
When you start messing around with Nagios, you’ll discover a wide selection of options and settings that can be configured. It is very easy to get lost in a maze of options.
So before we continue, keep this in mind. Start slowly with Nagios, adding additional checks only after you’ve confirmed whether the first ones worked correctly.