# Standalone TcpProxy Binaries

import { Callout } from 'nextra/components'

<Callout type="error">
**Deprecated.** The TcpProxy module is no longer actively developed. The [Stream module](/developers/rust/stream) provides the same functionality (familiar `AsyncRead`/`AsyncWrite` I/O over the Mixnet) with a simpler API, multiplexed connections, and sequence-based message reordering. Use Streams for new projects.
</Callout>

Standalone versions of the `TcpProxyClient` and `TcpProxyServer` [sdk module](/developers/rust/tcpproxy) can be found [here](https://github.com/nymtech/standalone-tcp-proxies/tree/main).

These can be a quick way to start proxying traffic through the mixnet, see what latency to expect, and check whether your application can tolerate it. They are also useful for server setups where several components run via init scripts and an extra process is acceptable.

## Build
```shell
cargo build --release
```

## Use
```shell
» ./target/release/proxy_server --help
Usage: proxy_server [OPTIONS] --upstream-tcp-address <UPSTREAM_TCP_ADDRESS>

Options:
  -u, --upstream-tcp-address <UPSTREAM_TCP_ADDRESS>
          Upstream address of the server process we want to proxy traffic to e.g. 127.0.0.1:9067
  -c, --config-dir <CONFIG_DIR>
          Config directory [default: /tmp/nym-tcp-proxy-server]
  -e, --env-path <ENV_PATH>
          Optional env filepath - if none is supplied then the proxy defaults to using mainnet else just use a path to one of the supplied files in envs/ e.g. ./envs/sandbox.env
  -h, --help
```

```shell
» ./target/release/proxy_client --help
Usage: proxy_client [OPTIONS] --server-address <SERVER_ADDRESS>

Options:
      --close-timeout <CLOSE_TIMEOUT>
          Send timeout in seconds [default: 30]
  -s, --server-address <SERVER_ADDRESS>
          Nym address of the NymProxyServer e.g. EjYsntVxxBJrcRugiX5VnbKMbg7gyBGSp9SLt7RgeVFV.EzRtVdHCHoP2ho3DJgKMisMQ3zHkqMtAFAW4pxsq7Y2a@Hs463Wh5LtWZUNyAmt4trcCbNVsuUhry1wpEXpVnAAfn
      --listen-address <LISTEN_ADDRESS>
          Listen address [default: 127.0.0.1]
      --listen-port <LISTEN_PORT>
          Listen port [default: 8080]
  -e, --env-path <ENV_PATH>
          Optional env filepath - if none is supplied then the proxy defaults to using mainnet else just use a path to one of the supplied files in envs/ e.g. ./envs/sandbox.env
      --client-pool-reserve <CLIENT_POOL_RESERVE>
          How many clients to have running in reserve for quick access by incoming connections [default: 2]
  -h, --help
          Print help
```

## Run
```shell
# set up the server on your remote machine, listening on the port your upstream process is expecting to communicate on (e.g. 127.0.0.1:9067).
# this will log the Nym address of the Nym Proxy Server to pass to the proxy_client
./target/release/proxy_server -u <UPSTREAM_TCP_ADDRESS>


# start your proxy client with the address of the server client. by default this listens on 127.0.0.1:8080
./target/release/proxy_client --server-address <SERVER_NYM_ADDRESS>

# now start your client process, directing its traffic to the listen port of your nym proxy client process. all traffic will now be proxied through the mixnet.
```

> You can run on another network by downloading on of the [env files](https://github.com/nymtech/nym/tree/nym-binaries-v2024.12-aero/envs) and passing that to both clients with `-e <PATH_TO_ENV_FILE>`

### A Note on Switching Networks
If you are running the `proxy_server` binary on one network and then switch to another, make sure to either specify a new env-specific directory for key and surb storage, or remove the existing one, before running the binary. Since the `proxy_client` relies on ephemeral clients, then this is not a problem for this binary.