> ## Documentation Index
> Fetch the complete documentation index at: https://e2b-mishushakov-disable-sdk-ref-cron.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Sandbox public URL
Every sandbox can be reached by a public URL, which lets you expose and connect to services running inside it. This page covers how to get that URL, connect to a server inside the sandbox, and customize the `Host` header services receive.
To control the sandbox's outbound internet access, see [Internet access](/docs/network/internet-access). To require authentication on the public URL, see [Restricting public access](/docs/network/restrict-public-access).
## Sandbox public URL
Every sandbox has a public URL that can be used to access running services inside the sandbox.
```js JavaScript & TypeScript highlight={6} theme={null}
import { Sandbox } from 'e2b'
const sandbox = await Sandbox.create()
// You need to always pass a port number to get the host
const host = sandbox.getHost(3000)
console.log(`https://${host}`)
```
```python Python highlight={6} theme={null}
from e2b import Sandbox
sandbox = Sandbox.create()
# You need to always pass a port number to get the host
host = sandbox.get_host(3000)
print(f'https://{host}')
```
The code above will print something like this:
```bash JavaScript & TypeScript theme={null}
https://3000-i62mff4ahtrdfdkyn2esc.e2b.app
```
```bash Python theme={null}
https://3000-i62mff4ahtrdfdkyn2esc.e2b.app
```
The first leftmost part of the host is the port number we passed to the method.
## Connecting to a server running inside the sandbox
You can start a server inside the sandbox and connect to it using the approach above.
In this example we will start a simple HTTP server that listens on port 3000 and responds with the content of the directory where the server is started.
```js JavaScript & TypeScript theme={null}
import { Sandbox } from 'e2b'
const sandbox = await Sandbox.create()
// Start a simple HTTP server inside the sandbox.
const process = await sandbox.commands.run('python -m http.server 3000', { background: true })
const host = sandbox.getHost(3000)
const url = `https://${host}`
console.log('Server started at:', url)
// Fetch data from the server inside the sandbox.
const response = await fetch(url);
const data = await response.text();
console.log('Response from server inside sandbox:', data);
// Kill the server process inside the sandbox.
await process.kill()
```
```python Python theme={null}
import requests
from e2b import Sandbox
sandbox = Sandbox.create()
# Start a simple HTTP server inside the sandbox.
process = sandbox.commands.run("python -m http.server 3000", background=True)
host = sandbox.get_host(3000)
url = f"https://{host}"
print('Server started at:', url)
# Fetch data from the server inside the sandbox.
response = requests.get(url)
data = response.text
print('Response from server inside sandbox:', data)
# Kill the server process inside the sandbox.
process.kill()
```
This output will look like this:
```bash JavaScript & TypeScript theme={null}
Server started at: https://3000-ip3nfrvajtqu5ktoxugc7.e2b.app
Response from server inside sandbox:
Directory listing for /
Directory listing for /
```
```bash Python theme={null}
Server started at: https://3000-ip3nfrvajtqu5ktoxugc7.e2b.app
Response from server inside sandbox:
Directory listing for /
Directory listing for /
```
## Masking request host headers
You can customize the `Host` header that gets sent to services running inside the sandbox using the `maskRequestHost` / `mask_request_host` option. This is useful when your application expects a specific host format.
```js JavaScript & TypeScript theme={null}
import { Sandbox } from 'e2b'
// Create sandbox with custom host masking
const sandbox = await Sandbox.create({
network: {
maskRequestHost: 'localhost:${PORT}'
}
})
// The ${PORT} variable will be replaced with the actual port number
// Requests to the sandbox will have Host header set to for example: localhost:8080
```
```python Python theme={null}
from e2b import Sandbox
# Create sandbox with custom host masking
sandbox = Sandbox.create(
network={
"mask_request_host": "localhost:${PORT}"
}
)
# The ${PORT} variable will be replaced with the actual port number
# Requests to the sandbox will have Host header set to for example: localhost:8080
```
The `${PORT}` variable in the mask will be automatically replaced with the actual port number of the requested service.