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README.md

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 # Fast ILO Exporter
+A basic prometheus exporter for HP servers with an ILO controller which uses SNMP (and optionally HTTPS) to attempt to strike a balance between frequency and detail of metrics.
+
+## testing
+I have tested this on a single server (my dl380p gen8) with ILO4, as I do not own any other servers with an ILO controller.
+
+It works for me, but might not for you.
+
+## Setting up the ILO
+HP does not allow reading SNMP by default, so you need to enable it.
+
+### SNMP
+1. Log into your ILO dashboard.
+2. Go to **Administration > Management**
+3. Under **SNMP Settings** set the **Read community** to whatever you want (but remember it for later!)
+4. Click **Apply**
+
+### HTTPS (optional)
+1. Log into your ILO dashboard.
+2. Go to **Administration > User Administration**
+3. Add a new user 
+   - Set the username and password to whatever you want (also remember this)
+   - I recommend not selecting any permissions, as they are not necessary
+
+## Setting up the exporter
+These steps are copied from my notes and detail the general process I go through to install any exporter. They were written to run on Debian 12.
+
+### download
+Grab the latest release from the [releases tab](https://github.com/Benjamin-Wiegand/ilo_exporter/releases).
+Replace `$DOWNLOAD_URL` with the appropriate download url.
+
+```bash
+cd ~
+curl $DOWNLOAD_URL -Lo ilo_exporter.tar.gz
+
+# extract
+tar -xvf ilo_exporter.tar.gz
+rm ilo_exporter.tar.gz
+```
+
+### install
+create a daemon user and prepare the file structure
+
+```bash
+# daemon user
+sudo adduser --system --group --shell /bin/false --home /opt/ilo_exporter iloexporter
+
+# move
+sudo mv ilo_exporter /opt/ilo_exporter/exporter
+
+# permissions
+sudo chown -R root:root /opt/ilo_exporter
+sudo chmod 0755 /opt/ilo_exporter
+
+# venv
+sudo apt install python3-venv
+sudo python3 -m venv /opt/ilo_exporter/venv
+source /opt/ilo_exporter/venv/bin/activate
+sudo pip install prometheus_client pysnmp requests
+```
+
+#### if using python >= 3.12:
+*asyncore, a dependency of pysnmp, was removed in python 3.12.*
+
+```bash
+sudo pip install pyasyncore
+```
+
+#### if also using HTTPS:
+```bash
+sudo touch /opt/ilo_exporter/ilo_credentials
+sudo chmod 0750 /opt/ilo_exporter/ilo_credentials
+
+# replace 'vim' with your editor of choice
+sudo vim /opt/ilo_exporter/ilo_credentials
+```
+Add these contents, making sure to replace `$USERNAME` and `$PASSWORD` with the credentials you picked in step 3 of [HTTPS server setup](#https-optional)
+```bash
+ILO_USERNAME="$USERNAME"
+ILO_PASSWORD="$PASSWORD"
+# uncomment and point to an SSL certificate if you have one
+#ILO_CERTIFICATE="/path/to/ssl/certificate.pem"
+```
+
+
+### test
+make sure it works
+
+```bash
+python /opt/ilo_exporter/exporter/main.py --help
+
+python /opt/ilo_exporter/exporter/main.py -i $ILO_ADDRESS -c $SNMP_COMMUNITY -v
+```
+
+### systemd service
+Make sure to replace 
+- `$ILO_ADDRESS` with your ILO controller address, and
+- `$ILO_COMMUNITY` with the community you picked in step 3 of [SNMP server setup](#snmp)
+```bash
+cat << 'EOF' | sudo tee /etc/systemd/system/ilo-exporter.service
+[Unit]
+Description=A fast(er) prometheus exporter for applicable HP servers using SNMP via the ILO controller.
+After=network-online.target
+
+[Service]
+User=iloexporter
+# uncomment if using HTTPS
+#EnvironmentFile=/opt/ilo_exporter/ilo_credentials
+WorkingDirectory=/opt/ilo_exporter/exporter
+# add --https-fans and/or --https-temperature to this to use HTTPS
+ExecStart=/opt/ilo_exporter/venv/bin/python -u /opt/ilo_exporter/exporter/main.py -i $ILO_ADDRESS -c $ILO_COMMUNITY
+Restart=on-failure
+KillMode=process
+
+# security
+PrivateTmp=true
+ProtectHome=true
+ProtectSystem=strict
+PrivateDevices=true
+NoNewPrivileges=true
+CapabilityBoundingSet=~CAP_SYS_ADMIN
+
+[Install]
+WantedBy=multi-user.target
+EOF
+
+sudo systemctl daemon-reload
+```
+
+```bash
+# enable
+sudo systemctl enable --now ilo-exporter
+
+# check status
+sudo systemctl status ilo-exporter
+
+# test
+curl localhost:6969
+
+# monitor logs
+sudo journalctl -xefu ilo-exporter
+```
+
+### updating
+Grab the latest release from the [releases tab](https://github.com/Benjamin-Wiegand/ilo_exporter/releases).
+Replace `$DOWNLOAD_URL` with the appropriate download url.
+
+```bash
+cd ~
+curl $DOWNLOAD_URL -Lo ilo_exporter.tar.gz
+
+# extract
+tar -xvf ilo_exporter.tar.gz
+rm ilo_exporter.tar.gz
+
+# replace old version
+sudo rm -rf /opt/ilo_exporter/exporter
+sudo mv ilo_exporter /opt/ilo_exporter/exporter
+
+# restart exporter
+sudo systemctl restart ilo-exporter
+
+# check status
+sudo systemctl status ilo-exporter
+```
+
+## Prometheus configuration
+nothing too special
+```yaml
+  - job_name: some-ilo
+    static_configs:
+      - targets: ['your-ilo-exporter:6969']
+```