Deploy a Single Node EloqKV Instance Using Eloqctl

eloqctl is a powerful tool designed for the operation and maintenance of EloqKV clusters. With Eloqctl, you can effortlessly manage daily database tasks, such as deploying, starting, stopping, upgrading, and decommissioning EloqKV clusters, as well as configuring cluster parameters.

eloqctl supports the deployment of various cluster types, including EloqKV transactional clusters, EloqKV log clusters, persistent storage clusters like Cassandra, and associated monitoring systems. This document provides guidance on deploying EloqKV cluster on a single node.

1. Prerequisites

EloqKV is compatible with Red Hat 8/9 and Ubuntu 20.04, 22.04, and 24.04.

Please ensure you've reviewed the following documents:

Configuration Checklist

2. Deploy eloqctl on the control machine

Get your eloqctl installation script here:

Eloqctl Install Script

To install eloqctl, simply run the following command:

bash eloqctl_installer.sh

If the following message is displayed, you have successfully installed eloqctl:

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 16.6M  100 16.6M    0     0   203M      0 --:--:-- --:--:-- --:--:--  205M
/home/eloq/.bash_profile has been modified to add eloqctl to PATH
===============================================
To use it, open a new terminal or execute:
source /home/eloq/.bash_profile
===============================================

This command installs eloqctl in the $HOME/.eloqctl directory, where the cluster metadata and downloaded components are also stored.

Please run source $HOME/.bash_profile to add $HOME/.eloqctl to the PATH environment variable, so you can use eloqctl directly.

Once installed, you can verify the eloqctl version by running:

eloqctl --version

3. Initialize the cluster topology file

Example cluster topology files can be found in the .eloqctl/config/examples/ directory.

You can select either eloqkv_rocksdb.yaml or eloqkv_cassandra.yaml to set up your EloqKV cluster. For a detailed comparison between the RocksDB and Cassandra storage engines, please refer to the EloqKV Introduction. In the following example, we will demonstrate how to set up the cluster topology file using RocksDB.

# example yaml file
.eloqctl/config/examples/eloqkv_rocksdb.yaml

Open the configuration file by running vi eloqkv_rocksdb.yaml to view its contents:

connection:
  username: "${USER}"
  auth_type: "keypair"
  auth:
    keypair: "/home/${USER}/.ssh/id_rsa"
deployment:
  cluster_name: "eloqkv-cluster"
  product: "EloqKV"
  version: "latest"
  install_dir: "/home/${USER}"
  tx_service:
    tx_host_ports: [127.0.0.1:6389]
    enable_cache_replacement: on
  # If you want to write wal log in your cluster, uncomment log_service section
  #log_service:
  #  nodes:
  #    - host: 127.0.0.1
  #      port: 9000
  #      data_dir:
  #        - "/home/${USER}/eloqkv-cluster/wal_eloqkv"
  #  replica: 1
  storage_service:
    rocksdb: Local
  monitor:
    data_dir: ""
    monograph_metrics:
      path: "/mono_metrics"
      port: 18081
    prometheus:
      download_url: "https://github.com/prometheus/prometheus/releases/download/v2.42.0/prometheus-2.42.0.linux-amd64.tar.gz"
      port: 9500
      host: 127.0.0.1
    grafana:
      download_url: "https://dl.grafana.com/oss/release/grafana-9.3.6.linux-amd64.tar.gz"
      port: 3301
      host: 127.0.0.1
    node_exporter:
      url: "https://github.com/prometheus/node_exporter/releases/download/v1.5.0/node_exporter-1.5.0.linux-amd64.tar.gz"
      port: 9200

Next, we'll provide detailed explanations for each configuration option available in the YAML file.

The connection section includes settings for connecting to EloqKV nodes from the control machine. If you followed the steps in the Prerequisite Document, you can leave the connection section unchanged.

The deployment section covers the configurations for deploying cluster metadata as well as the three key components: the transaction cluster, log cluster, and persistent storage cluster.

cluster_name:
Type: String
Default: 'eloqkv-cluster'
The name of the cluster being deployed serves as an identifier for the cluster. With eloqctl, you can deploy and manage multiple clusters, each distinguished by its unique name.
product:
Type: String
Default: 'EloqKV'
The product name being deployed should be set to 'EloqKV' for the current deployment. In the future, eloqctl will support the deployment of different database products like EloqSQL etc..
version:
Type: String
Default: 'latest'
Specifies the version of EloqKV to be installed. Setting this to 'latest' ensures that the most recent version is used.
install_dir:
Type: String
Default: '/home/${USER}'
Specifies the directory where the product will be installed. The ${USER} placeholder dynamically references the current user's home directory.
tx_service.tx_host_ports:
Type: List of Strings
Default: [127.0.0.1:6389]
The list of IP
addresses for the transaction service hosts. The transaction service handles Redis client requests and is compatible with the Redis Protocol. Note that each IP address can only be listed once.
tx_service.enable_cache_replacement:
Type: Boolean
Default: on
If persisted cold data can be evicted out of memory cache. If set to false, all data will be cached in memory and new data insertion will fail if memory is full. Less data can be stored in this mode, but all requests is handled in memory. If set to false, cold data will be evicted out of memory so that new write request can succeed. More data can be stored in this mode but a cache miss request will result in a disk read.
log_service.nodes:
Type: Composite
Specify the log service hosts. You can configure anywhere from zero to multiple log service nodes. Setting this to zero indicates that the Write-Ahead Log (WAL) is coupled with the transaction service, in which case you should remove the log_service section entirely. If you specify a non-zero value, the log service is decoupled from the transaction service, running as a standalone process. This can be deployed in a separate cluster or within the same cluster as the transaction service, depending on your requirements.
log_service.nodes.host:
Type: String
Default: '127.0.0.1'
The IP address where each log service process is running.
log_service.nodes.port:
Type: Integer
Default: 9000
The port on which each log service process listens.
log_service.nodes.data_dir:
Type: Strings
Default: ['/home/${USER}/disk_wal_kv']
The directory where each log service process stores its WAL logs. You can specify a separate disk for the log service to improve write throughput.
log_service.replica:
Type: Integer
Default: 1
The number of replicas for the log service. A value of 1 means there is only one replica. For high availability, set this to 3 or 5. Note that the number of log service nodes should be greater than the number of replicas.

The monitor section contains configurations for deploying a Prometheus and Grafana-based monitoring system for EloqKV. Monitoring is optional; if you do not wish to include it, simply remove the monitor section. If you choose to enable monitoring, set the prometheus.host and grafana.host fields to specify the locations of Prometheus and Grafana, and leave the other fields unchanged. Note that Prometheus and Grafana cannot be shared with other software, so you must ensure that the ports used by Prometheus and Grafana are not occupied by other processes.

monitor.grafana.host: Type: String
Default: '127.0.0.1'
The IP address where grafana service is running.
monitor.grafana.port: Type: Integer
Default: '3301'
The port on which grafana service listens.
monitor.prometheus.host: Type: String
Default: '127.0.0.1'
The IP address where prometheus service is running.
monitor.prometheus.host: Type: Integer
Default: '9500'
The port on which prometheus service listens.

4. Run the deployment command

After you modified the eloqkv_rocksdb.yaml. Use the eloqctl launch command to provision an EloqKV cluster

eloqctl launch ${HOME}/.eloqctl/config/examples/eloqkv_rocksdb.yaml -s

The command will install the EloqKV components in the specified cluster.

If you see the following message, the EloqKV cluster has been successfully provisioned:

Launch cluster finished, Enjoy!
Connect to server:
	/home/eloq/eloqkv-cluster/EloqKV/bin/eloqkv-cli -h 127.0.0.1 -p 6389
Prometheus: http://127.0.0.1:9500
Grafana: http://127.0.0.1:3301

Feel free to use eloqkv-cli or any other Redis client to connect to EloqKV and enjoy exploring its features.

Deploy a Single Node EloqKV Instance Using Eloqctl

1. Prerequisites​

2. Deploy eloqctl on the control machine​

3. Initialize the cluster topology file​

4. Run the deployment command​

1. Prerequisites

2. Deploy eloqctl on the control machine

3. Initialize the cluster topology file

4. Run the deployment command