Installing A Node using Node Binary

In this tutorial, we will be learning how to install a Harmony node using the node binary. The Harmony network is a powerful blockchain with EVM compatibility, sharding, and staking features. It is fully Ethereum compatible and inherits many tools and libraries from Ethereum, such as truffle, remix, and web3js. In order to install a node, we will first need to download the node binary from the Harmony website. We can then use this binary to set up the node using a configuration file or command line options. The tutorial will also cover opening the necessary ports on the host in order to allow for blockchain consensus messages and state syncing.

As per instructions on the cloud guides, the host needs to open up port 9000 for blockchain consensus messages and port 6000 for blockchain state syncing. Other ports are NOT necessary for syncing and should NOT be opened to the internet if you are staking only.

  • 9000 port is used for blockchain consensus messages (base port)

  • 6000 port is used for blockchain state syncing (base port – 3000)

  • 9500 port is used for SDK RPC service (base port + 500)

  • 9800 port is used for Websocket service (base port + 800)

The 9500, 9800 ports are only listened by localhost by default.

1. Download Node Binary

Before we proceed to the next steps we need to download the node binary first:

x86_64 (Mainnet)

curl -LO && mv binary harmony && chmod +x harmony

x86_64 (Testnet)

curl -LO && mv binary_testnet harmony && chmod +x harmony

arm64 (Mainnet)

curl -LO && mv binary-arm64 harmony && chmod +x harmony

Check the node binary version that was downloaded:

./harmony -V


Option 1: Setup Using Config File (recommended)

All the start options can be persisted and loaded from a single config file. To start a node, the following steps are also available**:**

  1. Dump the default config.
  2. Customize the config file.
  3. Run harmony node with the config file.

Dump the Default Config File


./harmony config dump harmony.conf


./harmony config dump --network testnet harmony.conf


A file harmony.conf is created and the default node options are set in the file in TOML formatting. Here is an example:

Version = "2.1.0"

  KMSConfigFile = ""
  KMSConfigSrcType = "shared"
  KMSEnabled = false
  KeyDir = "./.hmy/blskeys"
  KeyFiles = []
  MaxKeys = 10
  PassEnabled = true
  PassFile = ""
  PassSrcType = "auto"
  SavePassphrase = false

  Client = true
  LegacySyncing = false
  Port = 6000
  Server = true
  ServerPort = 6000
  Zone = ""

  DataDir = "./"
  IsArchival = false
  IsBeaconArchival = false
  IsOffline = false
  NoStaking = false
  NodeType = "validator"
  ShardID = -1

  Enabled = true
  IP = ""
  Port = 9500
  RosettaEnabled = false
  RosettaPort = 9700

  FileName = "harmony.log"
  Folder = "./latest"
  RotateSize = 100
  Verbosity = 3

    Config = false

  BootNodes = ["/dnsaddr/"]
  NetworkType = "mainnet"

  IP = ""
  KeyFile = "./.hmykey"
  Port = 9000

  Enabled = false
  ListenAddr = ""

  DebugEnabled = false
  RateLimterEnabled = true
  RequestsPerSecond = 1000

  Concurrency = 6
  DiscBatch = 8
  DiscHardLowCap = 6
  DiscHighCap = 128
  DiscSoftLowCap = 8
  Downloader = false
  Enabled = false
  InitStreams = 8
  MinPeers = 6

  BlacklistFile = "./.hmy/blacklist.txt"

  Enabled = true
  IP = ""
  Port = 9800

The content of the config file can be modified for the custom node start-up command.

For example, to open the public HTTP RPCs, change the field IP under [HTTP] tag to "":

  Enabled = true
  IP = ""
  Port = 9500
  RosettaEnabled = false
  RosettaPort = 9700

To run harmony internal nodes under legacy mode instead of staking mode, change the field NoStaking under [General] tag to true:

  DataDir = "./"
  IsArchival = false
  IsBeaconArchival = false
  IsOffline = false
  NoStaking = true
  NodeType = "validator"
  ShardID = -1

To enable stream sync, modify the below two sections (Experimental)


  Client = false
  LegacySyncing = false
  Port = 6000
  Server = true
  ServerPort = 6000
  Zone = ""
  Concurrency = 4
  DiscBatch = 8
  DiscHardLowCap = 4
  DiscHighCap = 1024
  DiscSoftLowCap = 4
  Downloader = true
  InitStreams = 4
  MinPeers = 4

Stream Sync is the new harmony Syncing method allowing to get rid of the previous sync via DNS causing issue when the DNS node wasn’t in sync.

Start the node with Config File

Harmony node binary is able to start with options provided by the config file:

//Start node
./harmony -c harmony.conf

The values stored in the config file will be read and parsed to harmony as node start options.

Option 2: Setup Using Flag Parsing

You can run your node binary using flag parsing:




./harmony --network testnet

A full list of active flags as well as examples can be accessed through running the binary with --help option:

Output :

Examples usage:

# start a validator node with default bls folder (default bls key files in ./.hmy/blskeys)

# start a validator node with customized bls key folder
    ./harmony --bls.dir [bls_folder]

# start a validator node with open RPC endpoints and customized ports
    ./harmony --http.ip= --http.port=[http_port] --ws.ip= --ws.port=[ws_port]

# start an explorer node
    ./harmony --run=explorer --run.archive --run.shard=[shard_id]

# start a harmony internal node on testnet
    ./harmony --run.legacy --network
  harmony [flags]
  harmony [command]

Available Commands:
  dumpconfig  dump the config file for harmony binary configurations
  help        Help about any command
  version     print version of the harmony binary

      --bls.dir string            directory for BLS keys (default "./.hmy/blskeys")
      --bls.keys strings          a list of BLS key files (separated by ,)
      --bls.kms                   enable BLS key decryption with AWS KMS service (default true)
      --bls.kms.config string     json config file for KMS service (region and credentials)
      --bls.kms.src string        the AWS config source (region and credentials) for KMS service (shared, prompt, file) (default "shared")
      --bls.pass                  enable BLS key decryption with passphrase (default true)
      --bls.pass.file string      the pass file used for BLS decryption. If specified, this pass file will be used for all BLS keys             after input the BLS passphrase from console, whether to persist the input passphrases in .pass file
      --bls.pass.src string       source for BLS passphrase (auto, file, prompt) (default "auto")
      --bootnodes strings         a list of bootnode multiaddress (delimited by ,)
  -c, --config string             load node config from the config toml file.
      --datadir string            directory of chain database (default "./")
      --dns.port int              port of customized dns node (default 9000) string           use customized peers from the zone for state syncing
  -h, --help                      help for harmony
      --http                      enable HTTP / RPC requests (default true)
      --http.ip string            ip address to listen for RPC calls. Use for public endpoint (default "")
      --http.port int             rpc port to listen for HTTP requests (default 9500)
      --log.dir string            directory path to put rotation logs (default "./latest")
      --log.max-size int          rotation log size in megabytes (default 100) string           log file name (e.g. harmony.log) (default "harmony.log")
  -v, --log.verb int              logging verbosity: 0=silent, 1=error, 2=warn, 3=info, 4=debug, 5=detail (default 3)
  -n, --network string            network to join (mainnet, testnet, pangaea, localnet, partner, stressnet, devnet) (default "mainnet")
      --p2p.keyfile string        the p2p key file of the harmony node (default "./.hmykey")
      --p2p.port int              port to listen for p2p protocols (default 9000)
      --pprof                     enable pprof profiling
      --pprof.addr string         listen address for pprof (default "")
      --run string                run node type (validator, explorer) (default "validator")
      --run.archive               run node in archive mode
      --run.legacy                whether to run node in legacy mode
      --run.shard int             run node on the given shard ID (-1 automatically configured by BLS keys) (default -1)
      --txpool.blacklist string   file of blacklisted wallet addresses (default "./.hmy/blacklist.txt")
  -V, --version                   display version info
      --ws                        enable websocket endpoint (default true)
      --ws.ip string              ip endpoint for websocket. Use for public endpoint (default "")
      --ws.port int               port for websocket endpoint (default 9800)

Use "harmony [command] --help" for more information about a command.


Option 3: Setup Using Flag Parsing and a Config file combined


If both config file and flag is provided, the node option stored in config file will be override by the values given in flag.

For example, In config file harmony.conf, HTTP server is enabled, and is open to public:

  Enabled = true
  IP = ""
  Port = 9500
  RosettaEnabled = false
  RosettaPort = 9700

And a flag is also provided during the node start command to disable the HTTP server:

./harmony -c harmony.conf --http=false

In this case, the command line flags will override the settings in the config file and thus the HTTP server is disabled.

> curl localhost:9500
curl: (7) Failed to connect to localhost port 9500: Connection refused

Non-Validating/Explorer Nodes

A Non-validating Node is a node that runs in archival mode and does not join the consensus.


Explorer Node: Recommendation

Setup: AWS i3en.12xlarge or equivalent, with local disk storage Storage: ~24TB (4x NVMe SSD) is recommended for Archival Explorer Nodes on Shard 0 OS: Latest Ubuntu Linux (LTS Version) Network: 100M+ bandwidth


Keep in mind that the storage space used increases around ~50+ GB per month on s0 due to staking transaction being stored. Other shard should take around 25GB per month. Please plan your storage space accordingly.

The following steps assume the node is connected to mainnet on shard 0, which is required for all exchanges.

If you are using the config file, which is the recommended way to configure your node, change the settings to the ones below:

 DataDir = "./"
 IsArchival = true
 IsBeaconArchival = false
 IsOffline = false
 NoStaking = true
 NodeType = "explorer"
 ShardID = 0

NoStaking = true will verify if the BLS keys in your .hmy/blskeys folder are part of the original FN keys. You will need add in the folder dummy empty files and remove all others

# remove all keys, save it before if necessary
rm -f .hmy/blskeys/*
# create dummy files
touch .hmy/blskeys/bls.key
touch .hmy/blskeys/bls.pass

IsBeaconArchival flag is applicable to explorer node only. For shard 1/2/3 the beacon shard 0 doesn’t need to be in archival mode. So to save space, the recommendation is to set to false. For shard 0 explorer node, IsArchival flag will determine if the database is in archival mode or not.

DataDir (or –db_dir below for cli flag) is the folder where the blockchain data will be store (ie location of harmony_db_0)

Alternatively, you can also run it using flag parsing:

./harmony --run=explorer --run.archive --run.shard=0 --db_dir=./

2. Setup Systemd


On this example, we will be installing the harmony daemon for user harmony on its home directory. Daemon will be configured with sudobut it will run with the harmonyuser at the end.

Create the harmony.service file:

//Create harmony.service file
sudo vi /etc/systemd/system/harmony.service

Add the content below to the file and save it. Change User to the local user you will be running the daemon and also WorkingDirectory to the home directory where you downloaded the harmony binary file previously. Parameter ExecStart needs to point to this same directory. On the example below we will be running the harmony binary using the harmony.conf file.

Description=Harmony daemon

ExecStart=/home/harmony/harmony -c harmony.conf


Give the necessary permissions to run the daemon service, enable it and start it:

sudo chmod 755 /etc/systemd/system/harmony.service
sudo systemctl enable harmony.service
sudo service harmony start

If you want to check the status of the daemon you can use:

sudo service harmony status

To restart, or stop the service daemon you can run:

sudo service harmony restart
sudo service harmony stop


You have now successfully installed a node on harmony network!

By this, you complete this workshop successfully!!