feat(book): basic pruning chapter (#4334)

book/run/pruning.md

@@ -0,0 +1,60 @@
+# Pruning
+
+> WARNING: pruning and full node are experimental features of Reth, 
+> and available only on `main` branch of the main repository now.
+
+By default, Reth runs as an archive node. Such nodes have all historical blocks and the state at each of these blocks
+available for querying and tracing.
+
+Reth also supports pruning of historical data and running as a full node. This chapter will walk through
+the steps for running Reth as a full node, what caveats to expect and how to configure your own pruned node.
+
+## Basic concepts
+
+- Archive node – Reth node that has all historical data from genesis.
+- Pruned node – Reth node that has its historical data pruned partially or fully through
+a [custom configuration](./config.md#the-prune-section).
+- Full Node – Reth node that has the latest state and historical data for only the last 128 blocks available
+for querying in the same way as an archive node.
+
+The node type that was chosen when first [running a node](./run-a-node.md) **can not** be changed after
+the initial sync. Turning Archive into Pruned, or Pruned into Full is not supported.
+
+## Modes
+### Archive Node
+
+Default mode, follow the steps from the previous chapter on [how to run on mainnet or official testnets](./mainnet.md).
+
+### Full Node
+
+To run Reth as a full node, follow the steps from the previous chapter on
+[how to run on mainnet or official testnets](./mainnet.md), and add a `--full` flag. For example:
+```bash
+RUST_LOG=info reth node \
+    --full \
+    --authrpc.jwtsecret /path/to/secret \
+    --authrpc.addr 127.0.0.1 \
+    --authrpc.port 8551
+```
+
+### Pruned Node
+
+To run Reth as a pruned node configured through a [custom configuration](./config.md#the-prune-section),
+modify the `reth.toml` file and run Reth in the same way as archive node by following the steps from
+the previous chapter on [how to run on mainnet or official testnets](./mainnet.md).
+
+## RPC support
+
+As it was mentioned in the [pruning configuration chapter](./config.md#the-prune-section), there are several parts
+which can be pruned independently of each other:
+- Sender Recovery
+- Transaction Lookup
+- Receipts
+- Account History
+- Storage History
+
+Pruning of each of these parts disables different RPC methods,  because the historical data or lookup indexes
+become unavailable.
+
+> TODO: `prune parts / RPC methods` table that shows which RPCs becomes unavailable when  certain parts of the data
+> are pruned