docker/cli · error

no name set for network

Error message

no name set for network

What it means

Thrown by parseNetworkAttachmentOpt when a network attachment entry has a blank Target after trimming whitespace. The Target field is the network name (or mode) the container attaches to; an empty value means the --network argument resolved to nothing parseable. This is a defensive guard before dereferencing the network mode downstream.

Solutions

1. Verify the --network value is non-empty: echo it before running docker, or guard with a shell default `--network "${NET:?NET must be set}"`.
2. Remove stray empty tokens from comma/space-separated network lists.
3. If building NetworkAttachmentOpts in Go, set Target to a real network name before calling parseNetworkAttachmentOpt.

Example fix

// before
NET=""
docker run --network "$NET" alpine

// after
NET="mynet"
docker run --network "$NET" alpine

func validNetworkTarget(target string) error {
    if strings.TrimSpace(target) == "" {
        return errors.New("no name set for network")
    }
    return nil
}

// before invoking docker run / parseNetworkAttachmentOpt:
for _, n := range networks {
    if err := validNetworkTarget(n); err != nil {
        return err
    }
}

When it happens

Trigger: Passing `--network=` (empty value) or `--network " "` (whitespace). Also reachable via programmatic calls that build a NetworkAttachmentOpts with an empty Target, or a malformed comma/space separated --network list producing an empty element (e.g. `--network mynet,,other`).

Common situations: Shell variable expansion yielding an empty string: `docker run --network "$NET"` when NET is unset. Compose/network config templates with an unfilled placeholder. Scripts splitting on a delimiter producing empty tokens.

Related errors

• container name cannot be empty
• cannot attach to a stopped container, start it first
• cannot attach to a paused container, unpause it first
• cannot attach to a restarting container, wait until it is…
• source can not be empty

AI-assisted analysis of docker/cli@4f84911bfe (2026-08-07). Data as JSON: /api/errors/309f0924a4c5455e. Report an issue: GitHub.

Appendix: source

Thrown at cli/command/container/opts.go:861

		}
	}
	if copts.ipv6Address != nil {
		if ipv6, ok := netip.AddrFromSlice(copts.ipv6Address.To16()); ok {
			n.IPv6Address = ipv6
		}
	}
	if copts.macAddress != "" {
		n.MacAddress = copts.macAddress
	}
	if copts.linkLocalIPs.Len() > 0 {
		n.LinkLocalIPs = toNetipAddrSlice(copts.linkLocalIPs.GetSlice())
	}
	return nil
}

func parseNetworkAttachmentOpt(ep opts.NetworkAttachmentOpts) (*network.EndpointSettings, error) {
	if strings.TrimSpace(ep.Target) == "" {
		return nil, errors.New("no name set for network")
	}
	if !container.NetworkMode(ep.Target).IsUserDefined() {
		if len(ep.Aliases) > 0 {
			return nil, errors.New("network-scoped aliases are only supported for user-defined networks")
		}
		if len(ep.Links) > 0 {
			return nil, errors.New("links are only supported for user-defined networks")
		}
	}

	epConfig := &network.EndpointSettings{
		GwPriority: ep.GwPriority,
	}
	epConfig.Aliases = append(epConfig.Aliases, ep.Aliases...)
	if len(ep.DriverOpts) > 0 {
		epConfig.DriverOpts = make(map[string]string)
		epConfig.DriverOpts = ep.DriverOpts
	}

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