nats-io/nats-server · error

config reload not supported for jetstream storage dir

Error message

config reload not supported for jetstream storage dir

What it means

Config reload rejects a change to the JetStream storage_dir because moving the storage location of a running server is unsupported; the reload differ's default branch catches the changed field and fails the reload with old vs new values. The server keeps running with the old storage directory; the new config is not applied.

Source

Thrown at server/reload.go:1995

		default:
			// TODO(ik): Implement String() on those options to have a nice print.
			// %v is difficult to figure what's what, %+v print private fields and
			// would print passwords. Tried json.Marshal but it is too verbose for
			// the URL array.

			// Bail out if attempting to reload any unsupported options.
			return nil, fmt.Errorf("config reload not supported for %s: old=%v, new=%v",
				field.Name, oldValue, newValue)
		}
	}

	// If not disabling JS but limits have changed then it is an error.
	if !disableJS {
		if jsMemLimitsChanged || jsFileLimitsChanged {
			return nil, fmt.Errorf("config reload not supported for jetstream max memory and max store")
		}
		if jsStoreDirChanged {
			return nil, fmt.Errorf("config reload not supported for jetstream storage dir")
		}
	}

	return diffOpts, nil
}

func copyRemoteGWConfigsWithoutTLSConfig(current []*RemoteGatewayOpts) []*RemoteGatewayOpts {
	l := len(current)
	if l == 0 {
		return nil
	}
	rgws := make([]*RemoteGatewayOpts, 0, l)
	for _, rcfg := range current {
		cp := *rcfg
		cp.TLSConfig = nil
		cp.tlsConfigOpts = nil
		rgws = append(rgws, &cp)
	}

View on GitHub (pinned to 3a66a489d2)

Solutions

1. Undo the storage_dir change in the config and reload
2. Stop the server, migrate/point to the new storage directory, and start it fresh
3. Use a symlink at the filesystem level instead of changing the config path

When it happens

Trigger: Thrown at server/reload.go:1995 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of nats-io/nats-server@3a66a489d2 (2026-09-02). Data as JSON: /api/errors/4849c61cf2c20c98. Report an issue: GitHub.