What does nv config save do?
Why B is the answer
Keeps the applied config across reboots
nv config save writes the applied configuration to the startup configuration, so it persists after a reboot. It is needed when auto save is off.
In detail
- Save writes it to the startup configuration.
- Auto save is on by default in current Cumulus Linux, so nv config apply normally saves as well. Use nv config save when auto save is off.
Use case
An illustrative scenario, not a real incident.
A team turns auto save off for a change window. After nv config apply, the change is live, and nv config save writes it to the startup configuration.
See it in different ways
flowchart LR A["nv set"] --> B["Pending revision"] B --> C["nv config diff"] C --> D["nv config apply"] D --> E["Saved by auto save, or nv config save"]
stateDiagram-v2 [*] --> Pending: nv set Pending --> Reviewed: nv config diff Reviewed --> Applied: nv config apply Applied --> Saved: auto save, or nv config save Saved --> [*]
flowchart TD
Q{"Is auto save on?"}
Q -->|"Yes, the default"| A0["nv config apply already saved it"]
Q -->|"No"| A1["Run nv config save"]Key point: Save keeps it across reboots when auto save is off.
Why the other options are wrong
- A. Reboots the switch at once
- It does not reboot.
- C. Displays the pending configuration
- That is nv config show.
- D. Deletes the last applied revision
- It does not delete anything.