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The following conventions apply to multiple areas of the configuration files for routers and controllers.


Listening and dialing addresses in OpenZiti are in the format of <protocol>:<ip-or-host>:<port> format.

For servers that are listening <ip-or-host> should be the address of an interface to listen on or "" for all IPv4 interfaces or "::" for all IPv6 interfaces. <port> should be a valid port number that the server should listen on.

For clients dialing a server the <ip-or-host> should be an IP address or hostname that resolves to the target server. <port> should be the port the server is listening on.

For clients and server, the <protocol> section is the protocol used to host or initiate the connection. It may be one of the following values, however tls is suggested for most scenarios.

  • tls
  • tcp
  • udp
  • dtls
  • ws
  • wss
  • transwarp
  • transwarptls

Environment Variables

All values in the configuration file support environment variable replacement. The environment variables are sourced from the scope of the executing process (i.e. controller, router). The syntax ${VARIABLE} is used.


db: ${ZITI_DATA}/db/ctrl.db


OpenZiti uses a common framework for loading, storing, and processing certificate and private key configuration. Identity sections all have a similar format. The use of the defined certificates is up to the implementing application. So see their configuration sections for details on which values are utilized for what. This documentation provides an overview useful to understand the "default" assumptions. The identity section may need to be formatted as YAML or JSON, depending on the implementing application. The ziti CLI and bundled sub-commands, e.g. ziti controller, ziti router, expect a configuration file formatted as YAML.

  • cert - (required) A string in the format of <engine>:<value> that defines a x509 client certificate
  • key - (required) A string in the format of <engine>:<value> that defines a private key used for cert and server_cert if server_key is not defined
  • server_cert -(optional) A string in the format of <engine>:<value> that defines a x509 certificate, if not defined cert is used
  • server_key - (optional) A string in the format of <engine>:<value> that defines a private key for server_cert, if not defined key is used if server_cert is defined
  • ca - (optional) A string in the format of <engine>:<value> that defines x509 certificate chain used to define trusted CAs
  • alt_server_certs - (optional) An array of objects with server_cert and server_key values used to add additional server certificates and keys not managed by OpenZiti (i.e. from public CAs like Let's Encrypt). The server name indication (SNI) of incoming requests is compared with all DNS subject alternative names (SAN) of the server certificates in identity.server_cert and identity.alt_server_certs[].server_cert. The first-matched server certificate is presented to the TLS client. You must use distinct DNS SANs to avoid ambiguity during server certificate selection.

The <engine>:<value> format is used to define multiple different source types. If the <engine>: part is omitted, it is assumed to be file:. The following engines are supported:

  • file - indicates that <value> is the path to a file
  • pem - indicates that <value> is an inline PEM string

Additional PKCS#11 engines such as and may be used if the library are present on the host machine. This allows for access to hardware backed private keys.

Example Identity Section (Client & Server use same key):

cert: "file:ctrl-client.cert.pem"
key: ctrl.key.pem
ca: ca-chain.cert.pem
- server_cert: lets_encrypt.cert.pem
- server_key: lets_encrypt.key.pem


Channel sections control different ways in which connections behave. It is controlled by the channel library. Sections that invoke the channel library support the following options section.

  • options - a set of optional connections options
    • maxQueuedConnects - (optional) the maximum number of connections to be accepted but awaiting initial messaging
    • maxOutstandingConnects - (optional) the maximum number of connection accepted and waiting for hello messaging to complete
    • connectTimeoutMs - (optional) the maximum number of milliseconds to wait for hello messaging to complete
      • writeTimeout - (optional) the maximum amount of time to wait when writing data to a connection

Time Units

Configurations that do not specify a unit of time in their name, support a variety of human-readable time units. The format supports single and combinations of values (e.g. 12s, 5m20s, 2h30m22s).

Supported units:

  • ns
  • us (or µs)
  • ms
  • s
  • m
  • h


The web section is powered by XWeb. XWeb allows web APIs to be defined in code and exposed on multiple interfaces/networks through configuration alone.


- name: all-apis-localhost
- interface:
newAddress: localhost:1280
cert: ctrl-client.cert.pem
server_cert: ctrl-server.cert.pem
key: ctrl.key.pem
ca: ca-chain.cert.pem
idleTimeout: 5000ms
readTimeout: 5000ms
writeTimeout: 100000ms
minTLSVersion: TLS1.2
maxTLSVersion: TLS1.3
- binding: health-checks
- binding: fabric
- binding: edge-management
- binding: edge-client

The structure of the web section is an array of API exposure options:

- name: API Exposure 1
- name: API Exposure 2

Each exposure has the following configuration options:

  • name - (required) a name used for logging and error messaging
  • bindPoints - (required) the interfaces, external addresses, and migration address options for this exposure
  • apis - (required) a list of APIs and their options from the list above
  • options - (optional) a set of options used to tune HTTP/TLS


bindPoints are used to instruct XWeb on where to listen for new connections. Each exposure can have multiple bind pints to have the same API listen on one or more interfaces/networks. Additionally, each interface listened on can have its own external address and migration address.

  • interface - (required) the interface and port to listen on ("" for all IPv4 interfaces, "::" for all IPv6 interfaces
  • identity - (optional, root identity) the certificates and keys to use for TLS
  • address - (required) the host:port combination that external devices can use to reach the exposed interface (ip or host name)
  • newAddress - (optional) when specified, newAddress will be sent to clients in the HTTP header ziti-ctrl-address

newAddress should only be specified when clients can use the new host:port combination to reach the specified APIs. This setting is used to migrate APIs between ip/hostnames.


The apis section defines which APIs will be hosted on this exposure. Different OpenZiti components support different APIs. See their documentation for a list of APIs supported.


  • idleTimeout - (optional) the maximum amount of time to wait for the next request when keep-alives are enabled, if IdleTimeout is zero, the value of ReadTimeout is used
  • readTimeout - (optional) the maximum duration for reading the entire request, including the body
  • writeTimeout - (optional) the maximum duration before timing out writes of the response, it is reset whenever a new request’s header is read
  • minTLSVersion - (optional) the minimum TLS version to support (TLS1.1, TLS1.2, TLS1.3)
  • maxTLSVersion - (optional) the maximum TLS version to support (TLS1.1, TLS1.2, TLS1.3)

xgress Components

"xgress" is an internal OpenZiti set of components that facilitate ingress and egress traffic from the OpenZiti mesh overlay network. Ingress traffic is handled by "listeners" and egress traffic is handled by "dialers". Internally, xgress components may be developed that support listeners (ingress), dialers (egress), or both.

Each xgress components are referenced to by binding name. The following binding values are currently defined:

  • proxy - listener only - allows ingress TCP connections to connect directly to a service defined in options
  • proxy_udp - listener only - allows ingress UDP connections to connect directly to a service defined in options
  • transport - listener, dialer - allows ingress TCP connections to request a circuit for a service and for traffic to dial to an underlay UDP service at a <host>:<port> address
  • transport_udp - listener, dialer - allows ingress UDP connections to request a circuit for a service and for traffic to dial to an underlay UDP service at a <host>:<port> address
  • edge - listener, dialer - allows multiplexed ingress connections from SDKs and connections to other SDKs hosting services, requires an advertise option in the options section to be defined for external linking
  • tunnel - a special type of binding used by routers

xgress Options

Each xgress component can have its own options in addition to the following shared options:

  • mtu - (optional, 640*1024) unused
  • randomDrops - (optional, false) true/yes/on or false/no/off to randomly drop 1 in drop1InN payloads, used for testing only
  • drop1InN - (optional, 100) if randomDrops is enabled, will drop 1 in N payloads, used for testing only
  • txQueueSize - (optional, 1) the number of transmit payload to queue
  • txPortalStartSize - (optional, 16*1024) integer that sets the starting window sizes
  • txPortalMinSize - (optional, 16*1024) integer that sets the minimum window size
  • txPortalMaxSize - (optional, 410241024) integer that sets the maximum window size
  • txPortalIncreaseThresh - (optional, 224) the number of successful transmits that triggers the window size to be scaled by txPortalIncreaseScale
  • txPortalIncreaseScale - (optional, 1.0) the scale factor to increase the window size by
  • txPortalRetxThresh - (optional, 64) the number of retransmissions that triggers the window size to be scaled by txPortalRetxScale
  • txPortalRetxScale - (optional, 0.75) the factor used to scale the window size when txPortalRetxThresh is reached
  • txPortalDupAckThresh - (optional, 64) the number of duplicate ACKs that triggers the window size to be scaled by txPortalDupAckScale
  • txPortalDupAckScale - (optional, 0.9) the factor used to scale the window size when txPortalDupAckScale is reached
  • rxBufferSize - (optional, 410241024) the size of the receive buffer
  • retxStartMs - (optional, 200) the number of milliseconds to wait before attempting to retransmit
  • retxScale - (optional, 1.5) the factor to scale retxStartMs based on RTT
  • retxAddMs - (optional, 0) a number of milliseconds to add to retxStartMs when calculating new retransmission thresholds
  • maxCloseWaitMs - (optional, 30s) the amount of time to wait for buffers to empty before closing a connection
  • getCircuitTimeout - (optional, 30s) the amount of time to wait for circuit creation
  • circuitStartTimeout - (optional, 3m) the amount of time to wait for a circuit to start
  • connectTimeout - (optional, 0s) the amount of time to wait for dialed connections to connect, 0/0s = OS default