Should Rocky Linux Enable NetworkManager‑wait‑online.service or Rely on network‑online.target for Service Startup Ordering?

Goal

Ensure that critical services in a Rocky Linux system only start once the network stack is fully operational, preventing repeated failures that appear in journalctl and systemctl status.

Constraint

NetworkManager controls IP assignment, but its “wait‑online” feature is optional. Without it, units that declare After=network-online.target may start before an interface is up, leading to AVC denials or bind failures. Enabling NetworkManager-wait-online.service guarantees the target is reached but can add measurable delay to boot.

Uncertainty

Both approaches are documented in the Rocky Linux systemd and NetworkManager manuals, yet the community has not reached consensus on which yields the most reliable ordering for production workloads.

Questions

• Which approach—enabling NetworkManager-wait-online.service or relying solely on network-online.target—provides the most consistent startup for services that require a fully configured interface?
• What measurable impact does enabling NetworkManager-wait-online.service have on boot time in typical enterprise deployments?
• Are there known edge‑case failures when a unit declares Wants=network-online.target without the wait service in Rocky Linux 9?