# Cronos EVM Mainnet This is a detailed documentation for setting up a full node on Cronos mainnet `cronosmainnet_25-1`. ## Pre-requisites ### Supported OS We officially support macOS, Windows, and Linux only. Other platforms may work but there is no guarantee. We will extend our support to other operating systems after we have stabilised our current architecture. ### Prepare your machine To run Cronos Mainnet nodes, you will need a machine with the following minimum requirements to run different types of nodes: * Pruned node (setting pruning=everything) * Storage: \~50G\* * RAM: 32G (LevelDB) or 64G RAM (RocksDB)\*\*\* * CPU: 4-core * Default full node (setting pruning=default) * Storage: \~1T\*\* * RAM: 32G (LevelDB) or 64G RAM (RocksDB)\*\*\* * CPU: 4-core * Archive node (setting pruning=nothing) * Storage: \~6T (LevelDB) or \~4.5T (RocksDB) * RAM: 32G (LevelDB) or 64G RAM (RocksDB)\*\*\* * CPU: 4-core *\*Only in case state-sync enabled.*\ \&#xNAN;*\*\* e.g. Note that size of snapshots from Quicksync will keep growing.*\ \&#xNAN;*\*\*\* Note that during a state-sync the node might require higher RAM than 3GB but, returns to normal after state-sync has finished.* {% hint style="info" %} Note that all depends on the type of node you are running and settings will vary depending on your usage. {% endhint %} {% tabs %} {% tab title="Mainnet" %} * [Seeds for Fullnode](https://github.com/crypto-org-chain/cronos-mainnet#seed-nodes) * [Genesis files](https://raw.githubusercontent.com/crypto-org-chain/cronos-mainnet/master/cronosmainnet_25-1/genesis.json) * Binaries for [Linux](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Linux_x86_64.tar.gz), Mac ([Intel x86](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Darwin_x86_64.tar.gz) / [M1](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Darwin_arm64.tar.gz)) and [Windows](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Windows_x86_64.zip) {% endtab %} {% endtabs %} ## Step 0 : Notes on Network Upgrade Before we start, please note that there was "*Huygen*" network upgrade at the block height `2,693,800`, which requires the node operator to update their Cronos Mainnet binary `cronosd` from `v0.6.*` to `v0.7.0`. For the host who would like to build a Full Node with complete blockchain data from scratch, one would need to:
Block HeightBinary VersionInstruction
1 ~ 2693800cronos_v0.6.*Start the node with the older binary version cronos_v0.6.*.
Sync-up with the blockchain until it reaches the target upgrade block height 2,693,800
2693800 ~ 3982500cronos_v0.7.0After it reaches the block height 2,693,800, update app.toml with new config items.

Update the binary to cronos_v0.7.0.

Restart the node.
3982500cronos_v0.8.3After reaching block height, update iavl-disable-fastnodein app.toml

Update the binary to cronos_v0.8.3 and restart the node
6542800cronos_v1.0.2

After reaching block height, update app-db-backend in app.toml. For[evm]max-tx-gas-wanted, it's recommended for validators to make the value as 500000.

Update the binary to cronos_v1.0.2.

Restart the node.

11608760cronos v1.0.15

After reaching block height, update the binary to v1.0.15.

Note: auto-pause the node before the upgrade height, we can restart cronosd with the flag --halt-height 11608759.


Restart the node.

13184000cronos v1.1.0After reaching block height, update the binary to v1.1.0

Please refer to the release note for config changes.

Restart the node.
13520000cronos v1.2.0

After reaching block height, update the binary to v1.2.0.

Restart the node.

14920000cronos v1.3.0

After reaching block height, update the binary to v1.3.0.

Restart the node.

17155000cronos v1.4.0

After reaching block height, update the binary to v1.4.0

For config changes, please refer to the release note for config changes.

Restart the node.

38432212cronos v1.5.1

After reaching block height, update the binary to cronos v1.5.1

Update query-gas-limit = "100000000 in app.toml.

Restart the node.

Users can refer to the [upgrade guide of "Huygen"](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-mainnet/upgrade-guide/huygen) for the detailed upgrade steps. {% hint style="info" %} To patch "unlucky" transactions, follow this guide on [patching unlucky tx](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-mainnet/patching-unlucky-tx) {% endhint %} ## Step 1. Get the Cronos Mainnet Binary {% hint style="info" %} Remarks: The following is the minimal setup for a **validator node** / **full node**. {% endhint %} To simplify the following step, we will be using **Linux** (Intel x86) for illustration.\ Binaries for **Mac** ([Intel x86](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Darwin_x86_64.tar.gz) / [M1](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Darwin_arm64.tar.gz)) and [Windows](https://github.com/crypto-org-chain/cronos/releases/download/v0.6.5/cronos_0.6.5_Windows_x86_64.zip) are also available. * To install released **Cronos Mainnet binaries** from github: * Create a new folder for the Install e.g. (cronosmainnet): 
$ cd cronosmainnet
$ curl -LOJ https://github.com/crypto-org-chain/cronos/releases/download/v0.6.11/cronos_0.6.11_Linux_x86_64.tar.gz
$ tar -zxvf cronos_0.6.11_Linux_x86_64.tar.gz
Afterward, you can check the version of `cronosd` by: ```bash $ cd cronosmainnet/bin $ ./cronosd version 0.6.11 ``` ## Step 2. Configure `cronosd` ### Step 2-0 (Optional) Clean up the old blockchain data * If you have joined `cronostestnet_338-3` before, you would have to clean up the old blockchain data and start over again, it can be done by running: ```bash $ ./cronosd unsafe-reset-all ``` and remove the old genesis file by ```bash $ rm ~/.cronos/config/genesis.json ``` Before kick-starting your node, we will have to configure your node so that it connects to the Cronos mainnet: ### Step 2-1 Initialize `cronosd` * First of all, you can initialize cronosd by: ```bash $ ./cronosd init [moniker] --chain-id cronosmainnet_25-1 ``` This `moniker` will be the displayed id of your node when connected to Cronos Chain network. When providing the moniker value, make sure you drop the square brackets since they are not needed. The example below shows how to initialize a node named `pegasus-node` : ```bash $ ./cronosd init pegasus-node --chain-id cronosmainnet_25-1 ``` {% hint style="info" %} Note: * Depending on your cronosd home setting, the cronosd configuration will be initialized to that home directory. To simply the following steps, we will use the default cronosd home directory `~/.cronos/` for illustration. * You can also put the `cronosd` to your binary path and run it by `cronosd` {% endhint %} ### Step 2-2 Configure cronosd * Download and replace the Cronos Mainnet `genesis.json` by: ```bash $ curl https://raw.githubusercontent.com/crypto-org-chain/cronos-mainnet/master/cronosmainnet_25-1/genesis.json > ~/.cronos/config/genesis.json ``` * Verify sha256sum checksum of the downloaded `genesis.json`. You should see `OK!` if the sha256sum checksum matches. ```bash $ if [[ $(sha256sum ~/.cronos/config/genesis.json | awk '{print $1}') = "58f17545056267f57a2d95f4c9c00ac1d689a580e220c5d4de96570fbbc832e1" ]]; then echo "OK"; else echo "MISMATCHED"; fi; OK! ``` {% hint style="info" %} NOTE For Mac environment, `sha256sum` was not installed by default. In this case, you may setup `sha256sum` with this command: ```bash function sha256sum() { shasum -a 256 "$@" ; } && export -f sha256sum ``` {% endhint %} * For network configuration, in `~/.cronos/config/config.toml`, validator nodes need to modify the configurations of `seed`, `create_empty_blocks_interval` and `timeout_commit` ```bash $ sed -i.bak -E 's#^(seeds[[:space:]]+=[[:space:]]+).*$#\1"0d5cf1394a1cfde28dc8f023567222abc0f47534@cronos-seed-0.crypto.org:26656,3032073adc06d710dd512240281637c1bd0c8a7b@cronos-seed-1.crypto.org:26656,04f43116b4c6c70054d9c2b7485383df5b1ed1da@cronos-seed-2.crypto.org:26656,337377dcda43d79c537d2c4d93ad3b698ce9452e@bd-cronos-mainnet-seed-node-01.bdnodes.net:26656"#' ~/.cronos/config/config.toml $ sed -i.bak -E 's#^(create_empty_blocks_interval[[:space:]]+=[[:space:]]+).*$#\1"5s"#' ~/.cronos/config/config.toml $ sed -i.bak -E 's#^(timeout_commit[[:space:]]+=[[:space:]]+).*$#\1"5s"#' ~/.cronos/config/config.toml ``` * If you would like to build an **archive node** that allows you to query all the historical block data - kindly update the pruning setting to `"nothing"` by ```bash $ sed -i.bak -E 's#^(pruning[[:space:]]+=[[:space:]]+).*$#\1"nothing"#' ~/.cronos/config/app.toml ``` {% hint style="info" %} NOTE For Mac environment, if `jq` is missing, you may install it by: `brew install jq` {% endhint %} ## Step 3. Run everything {% hint style="warning" %} CAUTION This page only shows the minimal setup for validator / full node. Furthermore, you may want to run full nodes as sentries (see [Tendermint](https://docs.tendermint.com/master/tendermint-core/running-in-production.html)), restrict your validator connections to only connect to your full nodes, test secure storage of validator keys etc. {% endhint %} Once `cronosd` has been configured, we are ready to start the node and sync the blockchain data: * Start cronosd, e.g.: ```bash $ ./cronosd start ``` {% hint style="info" %} Remarks: If you see errors saying `too many files opened...`, then you need to set a higher number for maximum open file descriptors in your OS. If you are on OSX or Linux, then the following could be useful: ```bash # Check current max fd $ ulimit -n # Set a new max fd $ ulimit -Sn [NEW_MAX_FILE_DESCRIPTOR] # Example $ ulimit -Sn 4096 ``` {% endhint %} * *(Optional for Linux)* Start cronosd with systemd service, e.g.: ```bash $ curl -s https://raw.githubusercontent.com/crypto-org-chain/cronos-docs/master/systemd/create-service.sh -o create-service.sh && curl -s https://raw.githubusercontent.com/crypto-org-chain/cronos-docs/master/systemd/cronosd.service.template -o cronosd.service.template $ chmod +x ./create-service.sh && ./create-service.sh $ sudo systemctl start cronosd # view log $ journalctl -u cronosd -f ``` {% hint style="info" %} Example: /etc/systemd/system/cronosd.service created by script ```bash # /etc/systemd/system/cronosd.service [Unit] Description=cronosd ConditionPathExists=/usr/local/bin/cronosd After=network.target [Service] Type=simple User=ubuntu WorkingDirectory=/usr/local/bin ExecStart=/usr/local/bin/cronosd start --home /home/ubuntu/.cronos Restart=on-failure RestartSec=10 LimitNOFILE=50000 [Install] WantedBy=multi-user.target ``` {% endhint %} It should begin fetching blocks from the other peers. * You can query the node syncing status by ```bash $ ./cronosd status 2>&1 | jq '.SyncInfo.catching_up' ``` If the above command returns `false`, It means that your node **is fully synced**; otherwise, it returns `true` and implies your node is still catching up. * One can check the current block height by querying the public full node by: ```bash curl -s https://rpc.cronos.org/commit | jq "{height: .result.signed_header.header.height}" ``` and you can check your node's progress (in terms of block height) by ```bash $ ./cronosd status 2>&1 | jq '.SyncInfo.latest_block_height' ``` ## Different ways to sync Cronos with snapshots The above outlines how to set up a node from scratch. Alternatively, you can set up a node using snapshots: {% content-ref url="cronos-evm-snapshots/quicksync" %} [quicksync](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-evm-snapshots/quicksync) {% endcontent-ref %} {% content-ref url="cronos-evm-snapshots/state-sync" %} [state-sync](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-evm-snapshots/state-sync) {% endcontent-ref %} {% content-ref url="cronos-evm-snapshots/public-node" %} [public-node](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-evm-snapshots/public-node) {% endcontent-ref %} {% content-ref url="cronos-evm-snapshots/ksync" %} [ksync](https://docs.cronos.org/~/changes/416/for-node-hosts/running-nodes/cronos-evm-snapshots/ksync) {% endcontent-ref %}