H12-831_V1.0 Exam Dumps : HCIP-Datacom-Advanced Routing & Switching Technology V1.0

A Layer 2 loop occurs when Ethernet frames circulate repeatedly through redundant switching paths without an effective loop-prevention mechanism.

Because Ethernet frames do not contain a TTL field equivalent to that used in IP packets, broadcast and unknown-unicast frames may continue circulating and multiplying.

This behaviour can create broadcast storms, causing excessive interface bandwidth utilization.

The resulting traffic volume can also overload the switch CPU, especially when large quantities of protocol or control packets are processed.

High CPU utilization can prevent administrators from logging in or cause the device to respond slowly to management operations.

Additionally, service interface indicators may blink unusually frequently because of the sustained traffic volume.

All four symptoms are consistent with Layer 2 loops. Huawei ' s troubleshooting documentation identifies these symptoms as indicators of switching loops.

In OSPFv3, several new LSA types were introduced to support IPv6. The Link-LSA and Intra-Area-Prefix-LSA have the following roles:

✅ Link-LSA is generated per link by each router. It includes:

Link-local IPv6 address

IPv6 prefix(es) associated with the link

Options related to the interface (bitfields)

✅ Intra-Area-Prefix-LSA describes IPv6 prefix information associated with a Router-LSA or a Network-LSA, rather than embedding it directly within them (as in OSPFv2).

❌ A device does not generate an Intra-Area-Prefix-LSA for each link; instead, it generates it per area, and it can contain multiple prefixes.

✅ Official Reference from Huawei:

" In OSPFv3, prefix information is no longer carried in Router-LSAs or Network-LSAs. Instead, Intra-Area-Prefix-LSAs are used to describe prefixes associated with them. "

" Each router generates one Link-LSA per link. The Link-LSA includes the link-local address and the list of IPv6 prefixes for the link. "

— [Huawei HCIA-Datacom Certification Guide – OSPFv3 Chapter]