# Configuration Files

To configure the Old Faithful RPC server, you create a YAML configuration file per epoch of data you want the server to support. 

You can provide as few or as many epochs as you want, just make sure each has it's own configuration file.

### Storage

Store the configuration files on disk in a folder that can be accessed by the Old Faithful binary.

A common folder structure is like this

<pre data-full-width="false"><code><strong>configs/
</strong>  epoch-0.yml
  epoch-2.yml
  epoch-3.yml
  ...
</code></pre>

### Old Faithful YAML Config File Format

* `version`: current version is 1
* `epoch`: the epoch that this config file is for, an Old Faithful server can only host one config per epoch
* `genesis`: (only used for epoch 0), provide a URI to a genesis file if you want to serve epoch 0.
* `data`: retrieval configuration for the block/transaction data&#x20;
  * `car`: used for [Filecoin v1,](/running-old-faithful/installation-and-setup/configuration-files/filecoin-v1-retrievals.md) [http](/running-old-faithful/installation-and-setup/configuration-files/http.md), and [local file system](/running-old-faithful/installation-and-setup/configuration-files/local-file-system.md) retrievals
  * `filecoin`: used for [Filecoin v2](/running-old-faithful/installation-and-setup/configuration-files/filecoin-v2-retrievals.md) retrievals
* `indexes`: retrieval configuration for the index data (each index header is a `uri` argument)
  * `slot_to_cid`: provide a local file system path or HTTP URI to the slot-to-cid index
  * `cid_to_offset_and_size`: provide a local file system path or HTTP URI to the cid-to-offset-and-size index
  * `sig_to_cid`: provide a local file system path or HTTP URI to the sig-to-cid index&#x20;
  * `sig_exists`: provide a local file system path or HTTP URI to the sig exists index
  * `gsfa`: provide a local file system path to an unpacked `gsfa` index folder.&#x20;
    * If you want to use a remote URI, you need to start the faithful RPC with `--gsfa-only-signatures.`

<details>

<summary>Sample config file</summary>

```yaml
epoch: 0 # epoch number (required)
version: 1 # version number (required)
data: # data section (required)
  car:
    # Source the data from a CAR file (car-mode).
    # The URI can be a local filepath or an HTTP url.
    # This makes the indexes.cid_to_offset_and_size required.
    # If you are running in filecoin-mode, you can omit the car section entirely.
    uri: /media/runner/solana/cars/epoch-0.car
  filecoin:
    # filecoin-mode section: source the data directly from filecoin.
    # If you are running in car-mode, you can omit this section.
    # if enable=true, then the data will be sourced from filecoin.
    # if enable=false, then the data will be sourced from a CAR file (see 'car' section above).
    enable: false
genesis: # genesis section (required for epoch 0 only)
  # Local filepath to the genesis tarball.
  # You can download the genesis tarball from
  # wget https://api.mainnet-beta.solana.com/genesis.tar.bz2
  uri: /media/runner/solana/genesis.tar.bz2
indexes: # indexes section (required)
  cid_to_offset_and_size:
    # Required when using a CAR file; you can provide either a local filepath or a HTTP url.
    # Not used when running in filecoin-mode.
    uri: '/media/runner/solana/indexes/epoch-0/epoch-0-bafyreifljyxj55v6jycjf2y7tdibwwwqx75eqf5mn2thip2sswyc536zqq-mainnet-cid-to-offset-and-size.index'
  slot_to_cid:
    # required (always); you can provide either a local filepath or a HTTP url:
    uri: '/media/runner/solana/indexes/epoch-0/epoch-0-bafyreifljyxj55v6jycjf2y7tdibwwwqx75eqf5mn2thip2sswyc536zqq-mainnet-slot-to-cid.index'
  sig_to_cid:
    # required (always); you can provide either a local filepath or a HTTP url:
    uri: '/media/runner/solana/indexes/epoch-0/epoch-0-bafyreifljyxj55v6jycjf2y7tdibwwwqx75eqf5mn2thip2sswyc536zqq-mainnet-sig-to-cid.index'
  sig_exists:
    # required (always); you can provide either a local filepath or a HTTP url:
    uri: '/media/runner/solana/indexes/epoch-0/epoch-0-bafyreifljyxj55v6jycjf2y7tdibwwwqx75eqf5mn2thip2sswyc536zqq-mainnet-sig-exists.index'
  gsfa: # getSignaturesForAddress index
    # optional; must be a local directory path.
    uri: '/media/runner/solana/indexes/epoch-0/gsfa/epoch-0-bafyreifljyxj55v6jycjf2y7tdibwwwqx75eqf5mn2thip2sswyc536zqq-gsfa.indexdir'
```

</details>


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