Environment Variables

The following is a (partial, but should cover most of the important ones) list of environment variables that can be used to configure Hysteria.

Variable	Type	Description
HYSTERIA_LOG_LEVEL	Logging	Log level (debug, info [default], warn, error)
HYSTERIA_LOG_FORMAT	Logging	Log format (console [default], json)
HYSTERIA_BRUTAL_DEBUG	Logging	Set to 1 to print information such as current RTT, packet loss, MTU, etc. every 2 seconds. Only applies when using Brutal as the congestion control algorithm.
HYSTERIA_BBR_DEBUG	Logging	Set to 1 to print BBR debug information. Only applies when using BBR as the congestion control algorithm.
HYSTERIA_DISABLE_UPDATE_CHECK	Update	Set to 1 to disable version update checks.
HYSTERIA_ACME_DIR	TLS	The directory to store ACME certificates in. If specified in the config file, this value will be ignored.
QUIC_GO_DISABLE_GSO	QUIC	Set to 1 to disable GSO (Generic Segmentation Offload) in quic-go. May solve compatibility issues on some systems.
QUIC_GO_DISABLE_ECN	QUIC	Set to 1 to disable ECN (Explicit Congestion Notification) in quic-go. May solve compatibility issues on some systems.