[Polkadot WIki Migration] Set up a RPC node

infrastructure/general/.pages

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 title: General Infrastructure
 nav:
   - index.md
+  - setup-rpc.md

infrastructure/general/setup-rpc.md

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+---
+title: Set up an RPC node
+description: Learn how to configure set up, secure, and maintain an RPC node in an archival or pruned state (and know the difference between the two).
+---
+
+The RPC server (included in all Polkadot SDK node implementations) can be accessed over the WebSocket protocol, which can be used to access the underlying network and/or validator node. By default, you can access your node's RPC
+server from `localhost` (for example, to rotate keys or do other maintenance). To access it from
+another server or an applications UI (such as [Polkadot.js](https://polkadot.js.org/apps){target=_blank}) it is
+recommended to enable access to the RPC node over an SSL connection and encrypt the connection
+between the end user and the RPC server. This can be achieved by setting up a secure proxy. Many
+browsers, such as Google Chrome, will block non-secure WS endpoints if they come from a different
+origin.
+
+!!!warning
+    Enabling remote access to your validator node shouldn't be necessary and isn't suggested, as it
+    can often lead to security problems. Learn more about node security in [Secure Your Validator](todo:link).
+
+## Set Up a Node
+
+Setting up any Polkadot SDK-based node relies on a similar process. For example, by default, they will
+all share the same WebSocket connection at port 9944 on localhost. In this example, you'll set up a
+Polkadot sync node on a Debian-flavored server (such as Ubuntu 22.04). Create a new server on your
+provider of choice or locally at home. See [Set up a Full Node](todo:link){target=_blank} for additional
+instructions. You can install from the default apt repository or build from scratch. The startup
+options in the setup process provide various settings that can be modified.
+
+A typical setting for an externally accessible Polkadot archive RPC node would be:
+
+```config
+polkadot --chain polkadot --name myrpc --state-pruning archive --blocks-pruning archive --rpc-max-connections 100 --rpc-cors all --rpc-methods Safe --rpc-port 9944
+```
+
+Or for a Polkadot pruned RPC node:
+
+```config
+polkadot --chain polkadot --name myrpc --state-pruning 1000 --blocks-pruning archive --rpc-max-connections 100 --rpc-cors all --rpc-methods Safe --rpc-port 9944
+```
+
+The specified flag options are outlined in greater detail below.
+
+### Archive Node vs. Pruned Node
+
+A pruned node only keeps a limited number of finalized blocks of the network, not its full history.
+Most frequently required actions can be completed with a pruned node, such as displaying account
+balances, making transfers, setting up session keys, staking, etc. An archive node has the full
+history (database) of the network. It can be queried in various ways, such as providing historical
+information regarding transfers, balance histories, and more advanced queries involving past events.
+
+An archive node requires a lot more disk space. At the start of April 2023, Polkadot disk usage was
+160 GB for a pruned node and 1 TB for an archive node. This value will increase with time. For an
+archive node, you need the options `--state-pruning archive --blocks-pruning archive` in your
+startup settings.
+
+### Secure the RPC Server
+
+The node startup settings allow you to choose _what_ to expose, _how many_ connections to expose
+and from where access should be granted through the RPC server.
+
+- _How many_ - You can set your maximum connections through `--rpc-max-connections`, for example
+`--rpc-max-connections 100`
+- _From where_ - by default, localhost and Polkadot.js can access the RPC server. You can change this by setting `--rpc-cors`, to allow access from everywhere you need `--rpc-cors all`
+- _What_ - You can limit the methods to use with `--rpc-methods`, an easy way to set this to a safe
+mode is `--rpc-methods Safe`
+
+### Secure the WebSocket Port
+
+To safely access your WebSocket (WS) connection over an SSL-enabled connection (needed for any SSL-enabled developer console), you
+have to convert the WS connection to a secure (WSS) connection by using a proxy and an SSL
+certificate, you can find instructions on [Setup Secure WebSockets](todo:link){target=_blank}.
+
+## Connecting to the Node
+
+Open [Polkadot.js](https://polkadot.js.org/apps){target=_blank} and click the logo in the top left to switch the
+node. Activate the "Development" toggle and input your node's address - either the domain or the IP
+address. Remember to prefix with `wss://`, and if you're using the 443 port, append `:443` like so:
+`wss://example.com:443`.
+
+![A sync-in-progress chain connected to Polkadot.js UI](/images/infrastructure/general/maintain-wss.webp)