Dang Hoang Viet (HarryDang) : Prometheus & Grafana - Monitor Cisco Devices use snmp

Preference: https://github.com/prometheus/snmp_exporter

Step 1:

install golang follow https://golang.org/doc/install :

wget https://golang.org/dl/go1.16.3.linux-amd64.tar.gz

Extract the archive you downloaded into /usr/local, creating a Go tree in /usr/local/go.

rm -rf /usr/local/go && tar -C /usr/local -xzf go1.16.3.linux-amd64.tar.gz
export PATH=$PATH:/usr/local/go/bin

Check Go version:

go version

Step 2:

We need to generate our snmp.yml for cisco devices ( you can check more details at here https://github.com/prometheus/snmp_exporter/tree/main/generator )

Due to the dynamic dependency on NetSNMP, you must build the generator yourself.

sudo apt-get install unzip build-essential libsnmp-dev p7zip-full
go get github.com/prometheus/snmp_exporter/generator
cd ${GOPATH-$HOME/go}/src/github.com/prometheus/snmp_exporter/generator

go build
make mibs

Add module cisco to generator.yml file before we rendering snmp.yml
i've put my generator.yml on github, replace community: Change_To_Your_Community with your
https://github.com/dhviet/dhv_script/blob/main/dhv_snmp_exporter_generator.yml

Now we can generate our snmp.yml:

export MIBDIRS=mibs
./generator generate

Step 3: Install snmp_exporter

Download snmp_exporter for your platform: https://github.com/prometheus/snmp_exporter/releases

wget https://github.com/prometheus/snmp_exporter/releases/download/v0.20.0/snmp_exporter-0.20.0.linux-amd64.tar.gz
tar -xzvf /home/dhviet/snmp_exporter-0.20.0.linux-amd64.tar.gz
mv /home/dhviet/snmp_exporter-0.20.0.linux-amd64/* /usr/local/snmp_exporter/

Create services for snmp_exporter

vi /etc/systemd/system/snmp_exporter.service

then paste parameters bellow into this file:

[Unit]
Description=Snmp_exporter
Wants=network-online.target
After=network-online.target
[Service]
User=root
Group=root
Type=simple
ExecStart=/usr/local/snmp_exporter/snmp_exporter \
--config.file=/usr/local/snmp_exporter/snmp.yml
[Install]
WantedBy=multi-user.target

Copy new snmp.yml you've generated above to /usr/local/snmp_exporter/

cp /root/go/src/github.com/prometheus/snmp_exporter/generator/snmp.yml /usr/local/snmp_exporter/

Start & enable snmp_exporter services

systemctl start snmp_exporter.service
systemctl enable snmp_exporter.service
systemctl status snmp_exporter.service

Check metric:

access to http://X.X.X.X:9116/ fill your IP target, module: cisco then click submit

Step 4: Add new job for prometheus.yml

vi /etc/prometheus/prometheus.yml

add new job like bellow to this file, replace X.X.X.X with your devices:

- job_name: '_dhv_snmp'
static_configs:
- targets: ['X.X.X.X'] # SNMP device.
metrics_path: /snmp
params:
module: [cisco]
relabel_configs:
- source_labels: [__address__]
target_label: __param_target
- source_labels: [__param_target]
target_label: instance
- target_label: __address__
replacement: 127.0.0.1:9116 # The SNMP exporter's real hostname:port.

Check then restart prometheus services