Xray-docs-next/docs/en/config/outbound.md

Outbound Proxies

Outbound connections are used for sending data and can use any of the available protocols listed in outbound protocols.

OutboundObject

The OutboundObject corresponds to a sub-element of the outbounds item in the configuration file.

::: tip The first element in the list serves as the main outbound. When there is no match or no successful match for the routing, the traffic is sent out by the main outbound. :::

{
  "outbounds": [
    {
      "sendThrough": "0.0.0.0",
      "protocol": "protocol name",
      "settings": {},
      "tag": "identifier",
      "streamSettings": {},
      "proxySettings": {
        "tag": "another-outbound-tag"
      },
      "mux": {}
    }
  ]
}

sendThrough: address

The IP address used to send data. It is effective when the host has multiple IP addresses, and the default value is "0.0.0.0".

It is allowed to fill in the IPv6 CIDR block (such as 114:514:1919:810::/64), and Xray will use the random IP address in the address block to initiate external connections. Network access, routing tables, and kernel parameters need to be configured correctly to allow Xray to bind to any IP within the address block.

For networks that use ndp to access, it is not recommended to set a subnet smaller than /120, otherwise it may cause NDP flood and a series of problems such as the router neighbor cache being filled up.

protocol: string

The name of the connection protocol. For a list of optional protocols, see Outbound Proxy in the left sidebar.

settings: OutboundConfigurationObject

The specific configuration content varies depending on the protocol. See OutboundConfigurationObject in each protocol for details.

tag: string

The identifier of this outbound connection, used to locate this connection in other configurations.

::: danger When it is not empty, its value must be unique among all tags. :::

streamSettings: StreamSettingsObject

The underlying transport method is the way the current Xray connects with other nodes.

proxySettings: ProxySettingsObject

The outbound proxy configuration. When the outbound proxy takes effect, the streamSettings of this outbound will not work.

mux: MuxObject

Specific configuration related to Mux.

ProxySettingsObject

{
  "tag": "another-outbound-tag"
}

tag: string

When specifying the identifier of another outbound, data emitted by this outbound will be forwarded to the specified outbound.

::: danger This forwarding method does not go through the underlying transport. If you need to use forwarding that supports the underlying transport, please use SockOpt.dialerProxy. :::

::: danger This option is incompatible with SockOpt.dialerProxy. :::

::: tip Compatible with v2fly/v2ray-core's configuration transportLayer. :::

MuxObject

The Mux feature distributes the data of multiple TCP connections on a single TCP connection. For implementation details, see Mux.Cool. Mux is designed to reduce the latency of TCP handshake, not to increase the throughput of connections. Using Mux for watching videos, downloading, or speed testing usually has negative effects. Mux only needs to be enabled on the client side, and the server side automatically adapts. Mux has an additional function: to run multiple UDP connections, i.e. XUDP.

MuxObject corresponds to the mux item in OutboundObject.

{
  "enabled": false,
  "concurrency": 8
}

enabled: true | false

Whether to enable Mux forwarding requests, default is false.

concurrency: number

Maximum concurrent connections. Minimum value is 1, maximum value is 1024. If this parameter is omitted or equal to 0, the value will be 8.

This value represents the maximum number of Mux connections that can be carried on a TCP connection. For example, when concurrency=8 is set, if the client sends 8 TCP requests, Xray will only send one actual TCP connection, and all 8 requests from the client will be transmitted through this TCP connection.

::: tip When filling in a negative number, such as -1, the mux module is not loaded. :::

xudpConcurrency: number

Use a new XUDP aggregate tunnel (that is, another Mux connection) to proxy UDP traffic and fill in the maximum number of concurrent sub-UoTs. minimum value 1, the maximum value 1024. If this parameter is omitted or equal to 0, UDP traffic will use the same path as TCP traffic.

::: tip When filling in negative numbers, such as -1, UDP will not be transmitted via Mux. The original UDP transmission method of the proxy protocol will be used. For example, Shadowsocks will use native UDP, VLESS will use UoT. :::

xudpProxyUDP443: string

Control how Mux handles proxied UDP/443 (QUIC) traffic:

• Default reject: Deny traffic (generaly, browsers will fall back to to TCP HTTP/2)
• allow: Allow connections.
• skip: The Mux module is not used to carry UDP 443 traffic. The original UDP transmission method of the proxy protocol will be used. For example, Shadowsocks will use native UDP, VLESS will use UoT.