Line cards are registered with the system by type, and the slot must be configured with the correct type before you can install an line card in that slot. When you install a new line card, the system checks whether or not a previous configuration is associated with the slot. The following rules apply when you install or replace an line card:
- When you install an line card and boot it up to an online state in a slot that was never occupied or configured, the module type information is automatically detected and saved to the database. No special configuration is required.
- If you install an line card in a slot that was previously occupied by an line card of the same type and the slot is configured for that same type, you can hot-swap the modules without powering off the line cards. No slot configuration changes are required.
- If the slot was previously configured for a different type of line card, the installation fails and the module is faulted with a "Type mismatch" error. A RASLog error message is generated. You must power off the line card and clear the slot configuration with the no linecard command before you can configure the slot for a new line card.
The slot configuration persists in the database even after the line card is physically removed, powered off, or faulted since it first came online. All configuration data associated with the slot is automatically preserved across reboot or hot-swap of the line card with the same type.