In BGP, the origin attribute of the routes imported using the import-route command is incomplete.

The BGP origin attribute is a well-known mandatory attribute that indicates the source of the path information. It has three possible values:

1. IGP (i): The route was originated within the local Autonomous System (AS) and advertised into BGP using the network command. This is the most preferred origin type.

2. EGP (e): The route was learned via the Exterior Gateway Protocol (EGP). This is now obsolete but the value is preserved for historical reasons.

3. Incomplete (?): The route's origin is unknown. This occurs when a route is redistributed into BGP from another routing protocol (e.g., static, OSPF, IS-IS) or from a different BGP process. The import-route command in Huawei's VRP is the mechanism for this redistribution, and as such, it marks the origin of these routes as Incomplete.

Therefore, the statement that the origin attribute of routes imported using the import-route command is incomplete is correct.

Why the Alternative is Incorrect:

The alternative, "False," is incorrect. If the statement were false, it would imply that the import-route command assigns a different origin attribute, such as IGP (i) or EGP (e). However, the IGP origin is exclusively reserved for routes injected via the network command, which signifies they originated within the AS's IGP. The import-route command, by definition, handles routes from external sources (relative to the BGP process), so their origin is considered unknown or Incomplete.

1. Huawei HedEx Documentation (Official Vendor Documentation): In the HCIP-Datacom-Core Technology V1.0 Training Material

the section on BGP route attributes explicitly states this behavior.

Reference: Huawei

HCIP-Datacom-Core Technology V1.0 Training Material

"BGP Path Attributes" section.

Content: "The origin attribute has three values: IGP

EGP

and Incomplete... Incomplete: A route is imported using the import-route command. This type of route has the lowest priority." This directly confirms that the import-route command sets the origin to Incomplete.

2. Huawei HedEx Documentation (Official Vendor Documentation): The command reference for Huawei's VRP operating system details the behavior of BGP commands.

Reference: Huawei VRP V800R012C10 BGP Command Reference

"import-route" command description.

Content: The documentation on BGP route import mechanisms clarifies that when routes are redistributed from an IGP or static routes into BGP

their origin is marked as Incomplete (?).

3. Internet Engineering Task Force (IETF) RFC 4271: This is the foundational standard for BGP-4 and defines the ORIGIN attribute.

Reference: IETF RFC 4271

"A Border Gateway Protocol 4 (BGP-4)"

Section 5.1.1 "ORIGIN".

Content: The RFC defines the value 2 for the origin attribute as INCOMPLETE

specifying it is for "Network Layer Reachability Information learned by some other means." Redistribution

as performed by the import-route command

falls directly into the category of "some other means."