Install Loki Binary and Start as a Service
Download and Install Loki Binary
To keep this as simple as possible, we will install the Loki binary as a service on our existing Grafana server.
To check the latest version of Grafana Loki, visit the Loki releases page. https://github.com/grafana/loki/releases/
sudo curl -fSL -o loki.gz "https://github.com/grafana/loki/releases/download/v1.6.1/loki-linux-amd64.zip"
sudo gunzip loki.gz
And allow the execute permission on the Loki binary
sudo chmod a+x loki
Create the Loki config
Now create the Loki config file.
sudo nano config-loki.yml
And add this text.
auth_enabled: false server: http_listen_port: 3100 ingester: lifecycler: address: 127.0.0.1 ring: kvstore: store: inmemory replication_factor: 1 final_sleep: 0s chunk_idle_period: 5m chunk_retain_period: 30s max_transfer_retries: 0 schema_config: configs: - from: 2018-04-15 store: boltdb object_store: filesystem schema: v11 index: prefix: index_ period: 168h storage_config: boltdb: directory: /tmp/loki/index filesystem: directory: /tmp/loki/chunks limits_config: enforce_metric_name: false reject_old_samples: true reject_old_samples_max_age: 168h chunk_store_config: max_look_back_period: 0s table_manager: retention_deletes_enabled: false retention_period: 0s
This default configuration was copied from https://raw.githubusercontent.com/grafana/loki/master/cmd/loki/loki-local-config.yaml and may change depending on any updates to loki.
Test Loki Works,
You can now test Loki by running
sudo ./loki -config.file ./config-loki.yml
Open a browser and visit,
http://[Your Server Domain or IP]:3100/metrics
Now stop the Loki server by pressing CTRL-C. Note that it may take a minute for the process to stop.
Configure Loki as a Service
Now we will configure Loki as a service so that we can keep it running in the background.
Create user specifically for the Loki service
sudo useradd --system loki
Create a file called loki.service
sudo nano /etc/systemd/system/loki.service
Add the script and save
[Unit] Description=Loki service After=network.target [Service] Type=simple User=loki ExecStart=/usr/local/bin/loki -config.file /usr/local/bin/config-loki.yml [Install] WantedBy=multi-user.target
Now start and check the service is running.
sudo service loki start sudo service loki status
We can now leave the new Loki service running.
If you ever need to stop the new Loki service, then type
sudo service loki stop sudo service loki status
If you reboot your server, the Loki Service may not restart automatically.
You can set the Loki service to auto restart after reboot by entering,
sudo systemctl enable loki.service
Note it may take a minute to stop.
When your Loki server is running, it may be accessible remotely. If you only want localhost to be able to connect, then type
iptables -A INPUT -p tcp -s localhost --dport 3100 -j ACCEPT iptables -A INPUT -p tcp --dport 3100 -j DROP iptables -L
After blocking port 3100 for external requests, you can verify that local request still work using
iptables settings will be lost in case of system reboot. You will need to reapply them manually,
sudo apt install iptables-persistent
This will save your settings into two files called,
Any changes you make to the iptables configuration won't be auto saved to these persistent files, so if you want to update these files with any changes, then use the commands,
iptables-save > /etc/iptables/rules.v4
iptables-save > /etc/iptables/rules.v6
If you see the error
"failed to flush user" "open /tmp/loki/chunks/...etc : permission denied"
Loki: Internal Server Error. 500. Internal Server Error
Data source connected, but no labels received. Verify that Loki and Promtail is configured properly.
You should check the owner of the folders configured in the storage_config section of the the config-loki.yml to match the name of the user configured in the loki.service script above.
My user is loki, and the folders begins with /tmp/loki so I recursively set the owner.
chown -R loki:loki /tmp/loki
You may need to restart the loki service and checking again its status.