Setting Up a Validator for f(x)Core

Information on how to join the mainnet (genesis.json file and seeds) is held in our fxcore repo.

Before setting up your validator node, make sure you've already gone through the Full Node Setup guide either with Binaries or with Docker.

If you plan to use a KMS (key management system), you should go through these steps first.

What is a Validator?

The role of a validator is to run a full-node and participate in consensus by broadcasting votes. Validators commit new blocks in the blockchain and receive rewards in exchange for their work. They must also participate in governance by voting on proposals. Validators are weighted according to their total stake.

Before you proceed to the next section, ensure that you have already set up a full-node.

Create Your Validator

⚠️ We support ledger for sending transactions, we recommend using ledger as it is more secure, note that such transactions require fxcore to be installed on both the remote vm and the host vm, which is a bit of a pain but worth doing.

  1. Create validator's token holding account

Here we will create a new token holding account for the validator which we will bind later to the node consensus.

fxcored keys add <_name> --algo secp256k1 --coin-type 118 --ledger --index 0

Note: This creates a new token holding account for you, do record the mnemonic phrase in a safe place. Take note of the address so that you can fund the account. The _name will be used again later.

For example:

fxcored keys add Ciri --algo secp256k1 --coin-type 118 --ledger --index 0


name: test
type: ledger/local
address: "..." 
pubkey: "..."
mnemonic: ""
threshold: 0
pubkeys: []

**Important** write this mnemonic phrase in a safe place.
It is the only way to recover your account if you ever forget your password.

word word word word...

if you already have an existing fx wallet and would like to import it you may run the following command and follow the prompts:

fxcored keys add <account_name> --recover
  1. Bind the node consensus and validator's token holding account

Now we will bind the node consensus and validator's token holding account, once this is done you will have successfully set up a validator!

⚠️ ⚠️ ⚠️ Couple of items to ensure before continuing

  • Ensure that entire node has synchronised to the latest block height, to prevent risk of being jailed

Using curl localhost:26657/status or fxcored status to check "catching_up":false. If "catching_up":true, please continue to wait until entire node has synchronised, this could take up to a day depending on network usage.

  • Ensure that your token holding account has enough FX tokens before creating a validator. For Testnet version, you may obtain FX tokens via FX Faucet. For more information on how to obtain FX tokens on Testnet.

A minimum of 100 FX is needed to create an active validator. You will need more than 100 testnet FX in your account because some is needed to pay for the creation of your validator. Note: FX has 18 decimal points.

Great! You can now bind the node consensus and validator's token holding account.

The command to run will be fxcored tx staking create-validator, copy the entire command below, after editing the required fields:

  • chain-id=dhobyghaut is set as our fxcore testnet chain ie dhobyghaut. for mainnet, set the chain-id=fxcore

  • gas="auto" automatically assesses the gas used for this create-validator transaction

  • gas-adjustment=1.2 there will be a 20% buffer added to the automatically assessed gas amount

  • gas-prices="4000000000000FX" this will be the gas price you will be paying for (you may check the gas price you will need to pay for your node)

  • from=<_name> this is the token holding account created above that you will be binding your consensus account to to create a validator

  • amount=100000000000000000000000FX this is the amount you will be self-delegating for your validator (currently it is set as 100,000 FX)

  • pubkey=$(fxcored tendermint show-validator) this is your pubkey of your validator

  • commission-rate="0.01" this is the commission you will be charging as a validator

  • commission-max-rate="0.20" The maximum commission rate which this validator can charge. This parameter cannot be changed after create-validator is processed

  • commission-max-change-rate="0.01" The maximum daily increase of the validator commission. This parameter cannot be changed after create-validator is processed

  • min-self-delegation="1000000000000000000" Minimum amount of FX the validator needs to have bonded at all time. If the validator's self-delegated stake falls below this limit, their entire staking pool will unbond

  • moniker="choose a moniker" This will be the name of your validator for easier identification

  • website="" This will be the website for delegators or the public to read more about your validator

  • details="To infinity and beyond!" You can add some additional details about your validator

If this does not work for you, please check the Common Problem section or get help on the forum. Before you proceed and set your validator up, make sure you do some final checks (ensure your .fxcore path is set correctly). If you are in the root folder:

curl -s | jq '.result.validator_info.pub_key'
cat .fxcore/config/priv_validator_key.json| jq .pub_key

Ensure both these outputs are the same.

fxcored keys parse $(cat .fxcore/config/priv_validator_key.json| jq -r '.address')
fxcored tendermint show-address

Ensure the second to the last value from the first command has the same output as the second command before running the following:

fxcored tx staking create-validator \
  --chain-id=dhobyghaut \
  --gas="auto" \
  --gas-adjustment=1.2 \
  --gas-prices="4000000000000FX" \
  --from=<_name> \
  --amount=500000000000000000000FX \
  --pubkey=$(fxcored tendermint show-validator) \
  --commission-rate="0.01" \
  --commission-max-rate="0.20" \
  --commission-max-change-rate="0.01" \
  --min-self-delegation="100000000000000000000" \
  --moniker="choose a moniker" \
  --website="" \
  --details="To infinity and beyond!" 

for Mainnet the ChainId should be fxcore


{"body":{"messages":[{"@type":"/cosmos.staking.v1beta1.MsgCreateValidator","description":{"moniker":"choose a moniker","identity":"","website":"","security_contact":"","details":""},"commission":{"rate":"0.010000000000000000","max_rate":"0.200000000000000000","max_change_rate":"0.010000000000000000"},"min_self_delegation":"1000000000000000000","delegator_address":"fx1egmy0ncxzuur504qlz9z0ykfa5cqdk0ap5tgxz","validator_address":"fxvaloper1egmy0ncxzuur504qlz9z0ykfa5cqdk0af9khcz","pubkey":{"@type":"/cosmos.crypto.ed25519.PubKey","key":"JWar8+3FHVppCQWH7S4w27eMhjkyxXqUYmnbo185B3g="},"value":{"denom":"FX","amount":"500000000000000000000"}}],"memo":"","timeout_height":"0","extension_options":[],"non_critical_extension_options":[]},"auth_info":{"signer_infos":[],"fee":{"amount":[{"denom":"FX","amount":"1020264000000000000"}],"gas_limit":"170044","payer":"","granter":""}},"signatures":[]}

confirm transaction before signing and broadcasting [y/N]: 

Note: Do record the validator_address as this is the only time you can see it on the terminal, or else you will have to use the explorer Testnet/Mainnet to obtain the validator_address. The explorer option can only be done if the binding is successful.

Hit y and enter! If successful, You will get an object data from the terminal with code = 0 similar to what is shown below.



When specifying commission parameters, the commission-max-change-rate is used to measure % point change over the commission-rate. E.g. 1% to 2% is a 100% rate increase, but only 1 percentage point.

Min-self-delegation is a stritly positive integer that represents the minimum amount of self-delegated voting power your validator must always have. A min-self-delegation of 100000000000000000000 means your validator will never have a self-delegation lower than 100 $FX

You can confirm that you are in the validator set by using a third party explorer for Testnet/Mainnet.

Get validator pubkey

Your fxvalconspub is used to create a new validator by staking tokens (this is the account used by the node consensus). You can find your validator pubkey by running:

fxcored tendermint show-validator

This command is very important for recovery of your validator in the future.

To check if node is running

ps -ef | grep fxcored

Edit Validator Description

You can edit your validator's public description. This info is to identify your validator, and will be relied on by delegators to decide which validators to stake to. Make sure to provide input for every flag below. If a flag is not included in the command the field will default to '[do-not-modify]'.

The <key_name> specifies which validator you are editing. If you choose to not include certain flags, remember that the --from flag must be included to identify the validator to update.

The --identity can be used as to verify identity with systems like Keybase or UPort. When using with Keybase --identity should be populated with a 16-digit string that is generated with a account. It's a cryptographically secure method of verifying your identity across multiple online networks. The Keybase API allows us to retrieve your Keybase avatar. This is how you can add a logo to your validator profile.

There are only a few parameters that can be edited they are listed below:

  • commission-rate string: The new commission rate percentage

  • details string: The validator's (optional) details (default "[do-not-modify]")

  • identity string: The (optional) identity signature (ex. UPort or Keybase) (default "[do-not-modify]")

  • moniker string: The validator's name (default "[do-not-modify]")

  • security-contract string: The validator's (optional) security contact email (default "[do-not-modify]")

  • website string: The validator's (optional) website (default "[do-not-modify]")

Note: The commission-rate value must adhere to the following invariants:

  • Must be between 0 and the validator's commission-max-rate

  • Must not exceed the validator's commission-max-change-rate which is maximum % point change rate per day. In other words, a validator can only change its commission once per day and within commission-max-change-rate bounds.

fxcored tx staking edit-validator \
  --new-moniker="choose a moniker" \
  --website="" \
  --identity=6A0D65E29A4CBC8E \
  --details="To infinity and beyond!" \
  --commission-rate="0.10" \
  --chain-id=dhobyghaut \
  --gas="auto" \
  --gas-adjustment=1.2 \
  --gas-prices="6000000000000FX" \

for Mainnet the ChainId should be fxcore

View Validator Description

View the validator's information with this command:

fxcored query staking validator <validator_address>

Track Validator Signing Information

In order to keep track of a validator's signatures in the past you can do so by using the signing-info command:

fxcored query slashing signing-info "$(fxcored tendermint show-validator)"

Unjail Validator

When a validator is "jailed" for downtime, you must submit an Unjail transaction from the operator account in order to be able to get block proposer rewards again (depends on the zone fee distribution).

fxcored tx slashing unjail --from=<key_name>

Confirm Your Validator is Running

Your validator is active if the following command returns anything:

fxcored query tendermint-validator-set | grep "$(fxcored tendermint show-address)"

You should now see your validator in one of the f(x)Core explorers. You are looking for the bech32 encoded address in the ~/.fxcore/config/priv_validator.json file.

To be in the validator set, you need to have more total voting power than the 100th validator.

Halting Your Validator

When attempting to perform routine maintenance or planning for an upcoming coordinated upgrade, it can be useful to have your validator systematically and gracefully halt. You can achieve this by either setting the halt-height to the height at which you want your node to shutdown or by passing the --halt-height flag to fxcored. The node will shutdown with a zero exit code at that given height after committing the block.

Common Problems

Problem #1: Copy pasting the entire fxcored tx staking create-validator command does not work for me

Get your _pubkey using fxcored tendermint show-validator.

You will have to type out the command as follows:

fxcored tx staking create-validator --chain-id dhobyghaut --gas auto --gas-adjustment 1.2 --gas-prices 6000000000000FX --from <_name> --amount 100000000000000000000000FX pubkey <_pubkey> --moniker "choose a moniker" --commission-rate 0.01 --commission-max-rate 0.20 --commission-max-change-rate 0.01 --min-self-delegation 1000000000000000000 --moniker "choose a moniker" --website "" --details "To infinity and beyond!"

for Mainnet the ChainId should be fxcore

Problem #2: My transaction keeps failing with insufficient fees

Example of the error as shown:

{"height":"0","txhash":"1BF7A7126EF2650AE66DA211D1EE0C41AF0FCA0EEB0F14503A2371A6541F698C","codespace":"sdk","code":13,"data":"","raw_log":"insufficient fees; got:  required: 1200000000000000000FX: insufficient fee","logs":[],"info":"","gas_wanted":"200000","gas_used":"0","tx":null,"timestamp":""}

You will have to add --fees to your command, to find out how much fees to input you can copy paste from the required that is given to you.

Example of input:

fxcored tx staking edit-validator --from <_name> --fees 1200000000000000000FX --new-moniker "test test"

Problem #3: My validator has voting_power: 0

Your validator has become jailed. Validators get jailed, i.e. get removed from the active validator set, if they do not vote on 500 of the last 10000 blocks, or if they double sign.

If you got jailed for downtime, you can get your voting power back to your validator. First, if fxcored is not running, start it up again:

fxcored start

Wait for your full node to catch up to the latest block. Then, you can unjail your validator

Lastly, check your validator again to see if your voting power is back.

fxcored status

You may notice that your voting power is less than it used to be. That's because you got slashed for downtime!

Problem #4: My fxcored crashes because of too many open files

The default number of files Linux can open (per-process) is 1024. fxcored is known to open more than 1024 files. This causes the process to crash. A quick fix is to run ulimit -n 4096 (increase the number of open files allowed) and then restart the process with fxcored start. If you are using systemd or another process manager to launch fxcored this may require some configuration at that level. A sample systemd file to fix this issue is below:

# /etc/systemd/system/fxcored.service
Description=f(x)Core Node

ExecStart=/home/ubuntu/go/bin/fxcored start


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