H35-211_V2.5 Exam Dumps : HCIP-Access V2.5

For IPv4 multicast, the MAC mapping uses 01-00-5E followed by the low-order 23 bits of the multicast IP address. Because an IPv4 multicast address has 28 variable bits (224/4), 5 bits are not mapped to the MAC. Therefore, 2⁵ = 32 distinct multicast IP addresses can map to the same multicast MAC address.

Huawei multicast guidance stresses IGMP version compatibility: devices running an earlier version must interoperate only with hosts using the same or earlier version, otherwise v3 messages may not be processed. In Huawei’s multicast feature guidance for access devices (OLT side vs. user side), the behavior documented is that when the device is operating in IGMPv2, IGMPv3 Report messages from terminals are not processed—interoperation is restored only after the terminal/device side is downgraded to v2 (often driven by periodic queries that induce hosts to respond in v2). This maps operationally to dropping unsolicited IGMPv3 Reports when the OLT is fixed to v2. Huawei also recommends ensuring the device runs an IGMP version the same as or later than member hosts to avoid such loss. Therefore, with OLT fixed at v2, an incoming v3 Join is discarded.

On Huawei VRP, Advanced IPv4 ACLs (which can match source IP, destination IP, and L4 port numbers) use the 3000–3999 numbering range.

2000–2999 = Basic IPv4 ACL (matches source IP only).

3000–3999 = Advanced IPv4 ACL (matches source/destination IP, protocol, ports).

4000–4999 = Layer 2 (MAC) ACL.

5000–5999 = User-defined/other ranges, not the standard advanced IPv4 range.

Therefore, to match IPs and ports, select 3000–3999.