nektos/act · error

conflicting options: cannot specify both --network-alias and

Error message

conflicting options: cannot specify both --network-alias and per-network alias

What it means

Error [93]: In copyDir, CopyToContainer of the whole-workspace tar (destination '/') failed after a successful seek. This uploads the project directory into the job container. Wrapped causes: stream too large/timeout, container died, ENOSPC, or daemon API errors on big payloads.

Source

Thrown at pkg/container/docker_cli.go:820

		// and only a single network is specified, omit the endpoint-configuration
		// on the client (the daemon will still create it when creating the container)
		if i == 0 && len(copts.netMode.Value()) == 1 {
			if ep == nil || reflect.ValueOf(*ep).IsZero() {
				continue
			}
		}
		endpoints[n.Target] = ep
	}
	if hasUserDefined && hasNonUserDefined {
		return nil, errors.New("conflicting options: cannot attach both user-defined and non-user-defined network-modes")
	}
	return endpoints, nil
}

func applyContainerOptions(n *opts.NetworkAttachmentOpts, copts *containerOptions) error { //nolint:gocyclo
	// TODO should we error if _any_ advanced option is used? (i.e. forbid to combine advanced notation with the "old" flags (`--network-alias`, `--link`, `--ip`, `--ip6`)?
	if len(n.Aliases) > 0 && copts.aliases.Len() > 0 {
		return errors.New("conflicting options: cannot specify both --network-alias and per-network alias")
	}
	if len(n.Links) > 0 && copts.links.Len() > 0 {
		return errors.New("conflicting options: cannot specify both --link and per-network links")
	}
	if n.IPv4Address.IsValid() && copts.ipv4Address != nil {
		return errors.New("conflicting options: cannot specify both --ip and per-network IPv4 address")
	}
	if n.IPv6Address.IsValid() && copts.ipv6Address != nil {
		return errors.New("conflicting options: cannot specify both --ip6 and per-network IPv6 address")
	}
	if n.MacAddress != "" && copts.macAddress != "" {
		return errors.New("conflicting options: cannot specify both --mac-address and per-network MAC address")
	}
	if len(n.LinkLocalIPs) > 0 && copts.linkLocalIPs.Len() > 0 {
		return errors.New("conflicting options: cannot specify both --link-local-ip and per-network link-local IP addresses")
	}
	if copts.aliases.Len() > 0 {
		n.Aliases = make([]string, copts.aliases.Len())

View on GitHub (pinned to 4f41128141)

Solutions

1. Add large dirs to .gitignore (copyDir honors it): node_modules/, dist/, target/, .git kept as needed — or clean the workspace before act
2. Check disk on host: df -h; prune: docker system prune -a Increase daemon max request size / use a local socket instead of tcp
3. Re-run — if it fails at a consistent size, it's disk or payload; if randomly, it's the connection

Example fix

# before: giant untracked dirs shipped into container
# after: .gitignore	node_modules/
.gitignore	dist/
.gitignore	target/

// Estimate workspace size before act
cmd := exec.Command("du", "-sh", ".")
out, _ := cmd.Output() // warn above a threshold (e.g. >500M)

if err != nil && strings.Contains(err.Error(), "failed to copy content to container") && isBigWorkspace {
	// fall back: archive with tar externally and docker cp, or reduce workspace
}

When it happens

Trigger: Uploading a large workspace (many files, big node_modules/vendor dirs) where the daemon stream breaks; container exited during upload; host overlay disk full; remote DOCKER_HOST with bandwidth limits dropping the hijacked stream.

Common situations: Forgetting .gitignore coverage so build outputs get tarred; huge .git history; running act over ssh-tunneled docker sockets on slow links; CI runners with disk pressure.

Related errors

• conflicting options: cannot specify both --restart and --rm
• --health-start-interval cannot be negative
• conflicting options: cannot specify both --link and per-netw
• --pid: invalid PID mode
• --uts: invalid UTS mode

AI-assisted analysis of nektos/act@4f41128141 (2026-08-15). Data as JSON: /api/errors/ae8ef65d4a3d53b7. Report an issue: GitHub.