Guide

Environment Variables

Ze reads environment variables for daemon-wide settings and BGP protocol tuning. Config-backed keys have matching paths under environment { }. Bootstrap, safety, and test keys can be environment-only.

See environment.md for the authoritative list.

Priority for Config-Backed Keys

OS environment variable (shell, systemd EnvironmentFile, container runtime)
Config file environment { ... } block
Built-in default

An OS env var is never overwritten by a config value.

Common Variables

Variable	Purpose
`ze.user`	User to drop to after binding privileged ports
`ze.pid.file`	Path to PID file written at startup, removed at clean shutdown
`ze.pprof`	Bind pprof HTTP server (e.g. `:6060`). Empty disables
`ze.hide-version`	Keep the `X-Ze-Version` build banner off every HTTP response. Default false
`ze.bgp.openwait`	Seconds to wait for peer OPEN after TCP connect
`ze.bgp.announce.delay`	Duration to block between reactor Ready and first UPDATE
`exabgp.api.ack`	ExaBGP bridge: emit `done`/`error` ack lines on plugin stdin
`ze.web.certificate`	PKI store entry the web HTTPS listener serves. Empty means self-signed
`ze.looking-glass.certificate`	PKI store entry the looking glass serves. Empty means self-signed

Config Block Syntax

The same knobs can be expressed in the config file:

environment {
    daemon {
        pid "/run/ze.pid"
        user "zeuser"
    }
    bgp {
        openwait 60
        announce-delay 5s
    }
    pprof ":6060"
    hide-version true
    exabgp {
        api {
            ack false
        }
    }
    chaos {
        seed 0
        rate "0.1"
    }
    reactor {
        cache-ttl 60
    }
    log {
        level INFO
        bgp.routes debug
    }
}

Discoverability

Shell completion offers env-key suggestions after ze env get and ze env registered using canonical dot-form keys. Concrete ze.log.<subsystem> keys (visible in ze env list) are completable and inspectable via ze env get.

In the interactive CLI operational mode, show env get and show env registered also offer env-key completion through the shared command tree. wireEnvHints spells the show in those two paths as command.VerbShow, the verb registry's own constant, so renaming the read verb moves the completion paths with it.

Changes in 2026-04

The ExaBGP compatibility surface was trimmed. Every ze.bgp.daemon.*, ze.bgp.log.*, ze.bgp.tcp.*, ze.bgp.api.*, and ze.bgp.debug.* variable was either renamed, dropped, or plumbed from a YANG leaf to a new env key:

Old	New / Action
`ze.bgp.daemon.pid`	Plumbed to `ze.pid.file` (YANG leaf kept)
`ze.bgp.daemon.user`	Plumbed to `ze.user` (YANG leaf kept)
`ze.bgp.daemon.daemonize`, `drop`, `umask`	Dropped (use systemd unit file)
`ze.bgp.log.level`, `destination`, `short`	Dropped (slogutil owns `ze.log.*`)
`ze.bgp.tcp.attempts`	Dropped (test harness sends SIGTERM)
`ze.bgp.tcp.delay`	Dropped; new `ze.bgp.announce.delay` duration
`ze.bgp.tcp.port`	Renamed `ze.test.bgp.port` (test infrastructure only)
`ze.bgp.tcp.acl`	Dropped (experimental, unimplemented)
`ze.bgp.bgp.openwait`	Renamed `ze.bgp.openwait`
`ze.bgp.cache.attributes`	Dropped (caching is architectural)
`ze.bgp.debug.pprof`	Renamed `ze.pprof` (process-wide)
`ze.bgp.debug.*` (pdb/memory/rotate/etc.)	Dropped (use `go tool pprof`, `ze.log`)
`ze.bgp.api.ack`	Dropped; `exabgp.api.ack` handles bridge ack
`ze.bgp.api.chunk`, `encoder`, `respawn`, ...	Dropped (Ze manages plugins)

The ze exabgp migrate --env tool converts surviving keys to Ze YANG blocks and emits # <key> -- no longer supported comments for dropped ones so an operator can audit an ExaBGP env file before commit.