Руководство По Проектированию для Cisco Cisco Nexus 5010 Switch
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nexus5500-1(config-vpc-domain)# delay restore ?
<1-3600> Delay in bringing up the vPC links (in seconds)
interface-vlan Delay in bringing-up interface-vlan
If there are no SVIs configured because you are using the Cisco Nexus 5000 Series in Layer 2 mode, you may
want to lower the delay restore interface VLAN timer value to 1 second.
Multicast Traffic
Under normal conditions, the peer link does not carry a significant amount of traffic because unicast traffic enters
and exits the Cisco Nexus 5000 Series Switch from one of the vPC member ports. Other traffic types use the peer
link:
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Traffic destined for orphan ports
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Multicast traffic and broadcast traffic
Figure 17 shows how multicast works with vPC. When a server joins a multicast group, it sends an IGMP report,
which is synchronized between the vPC peers (N5k01 and N5k02). This synchronization is performed to associate
the multicast MAC addresses of that given multicast group with the vPC member port on the peer Cisco Nexus
5000 Series Switch.
Note: Prior to Cisco NX-OS 5.0(3)N1(1a), when a vPC switch was reloaded, or when the peer link flapped,
IGMP entries that had been learned by a vPC peer would not be automatically synchronized with the other peer,
IGMP entries that had been learned by a vPC peer would not be automatically synchronized with the other peer,
resulting in slower convergence times. Starting from Cisco NX-OS 5.0(3)N1(1a), the restoration of the peer link
triggers a bulk synchronization of the IGMP entries from one vPC peer to the other, to reduce traffic loss.
When a multicast stream arrives from the aggregation layer, it can be hashed to either Cisco Nexus 5000 Series
Switch (N5k01 or N5k02; in Figure 17, it is N5k02). Both vPC peers have the multicast entry already associated
with the receiver (server 1 in the figure). This multicast stream not only is sent to the receiver but also over the vPC
peer link, in case there are other single-attached subscribers on N5k01. Server 1 on N5k01 does not receive a
duplicate copy because the vPC duplicate prevention mechanism intervenes and prevents the frames from
reaching vPC member ports.