Environment Variables

The following environment variables are supported and can be added to Docker/Podman containers or Kubernetes Pods

Variable	Description	Default	Current
SMTPROXY_SERVER_NAME	Server name	`<OS Hostname>`	mailprox.example.com
SMTPROXY_LISTEN_ADDR	STARTTLS listen address	:25	:25
SMTPROXY_TLS_LISTEN_ADDR	TLS listen address	:465	:465
SMTPROXY_METRICS_LISTEN_ADDR	Metrics listen address	:9100	:9100
SMTPROXY_UPSTREAM	List of upstream servers	:1025	[:1025]
SMTPROXY_ROUTING_MODE	Routing mode	failover	failover
SMTPROXY_DNS_SERVERS	DNS Servers	[]	[1.2.3.4]
SMTPROXY_REQUIRE_TLS	Require TLS	true	true
SMTPROXY_UPSTREAM_STARTTLS	Upstream use STARTTLS	true	true
SMTPROXY_UPSTREAM_REQUIRE_TLS	Upstream requires TLS	true	true
SMTPROXY_UPSTREAM_TLS	Upstream implicit TLS	false	false
SMTPROXY_TLS13_ONLY	TLS13 only	false	false
SMTPROXY_UPSTREAM_TLS13_ONLY	Upstream TLS13 only	false	false
SMTPROXY_SKIP_CERT_VALIDATION	Skip cert validation	false	false
SMTPROXY_SEND_XCLIENT	XCLIENT to signal IP	false	false
SMTPROXY_MAX_CONNECTIONS	Maximum sessions	1000	1000
SMTPROXY_TRUSTED_ROOT_FILE	Trusted root file	`<System trust store>`	[]
SMTPROXY_CERT_DIR	Certificate directory	/tls	/tls
SMTPROXY_MICROCA_CURVE_NAME	Optional MicroCA CurveName	[]	[]
SMTPROXY_CLIENT_TIMEOUT	Client timeout (sec)	120	2m0s
SMTPROXY_SHUTDOWN_SECONDS	Max shutdown time (sec)	60	60
SMTPROXY_CERT_UPDATE_CHECK_SECONDS	Cert Update Check (sec)	300	300
SMTPROXY_LOGLEVEL	Log level	ERROR	ERROR
SMTPROXY_HANDSHAKE_LOGLEVEL	Handshake Log level	NONE	NONE

Routing mode values:

There are five standard log levels from NONE to DEBUG Th default log level is ERROR.

Level	Description
NONE	Log nothing.
ERROR	Log only errors and failures.
INFO	Log important connection, protocol, and TLS state changes.
VERBOSE	Log additional operational details useful for tracing normal flow.
DEBUG	Log full debug and protocol trace output, including client/upstream command and response flow.