Link Redundancy - Avaya 8800 Planning And Engineering

and full-duplex mode, either you cannot synchronize the two CPUs, or the synchronization
may take a long time. Error messages can appear on the console.
In HA mode, Avaya recommends that you do not configure the OSPF hello timers for less than
one second, and the dead router interval for less for than 15 seconds.
HA mode and short timers
Prior to Release 5.0, protocols that used short timers could bounce (restart) during HA failover.
These protocols include VLACP, LACP, VRRP, OSPF, and STP. Release 5.0 introduces
enhancements that support fast failover for configurations that use short timers. In Release
7.0 and later:
All HA configurations that use R or RS modules in R mode, along with the 8895 SF/CPU or
8692 SF/CPU with SuperMezz, support protocols with short timers. Fast failover under these
conditions is supported.

Link redundancy

Provide link layer redundancy to ensure that a faulty link does not cause a service interruption.
The sections that follow explain design options that you can use to achieve link redundancy.
These mechanisms provide alternate data paths in case of a link failure.
Link redundancy navigation
• MultiLink Trunking
• 802.3ad-based link aggregation
• Bidirectional Forwarding Detection
• Multihoming
Planning and Engineering — Network Design
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Link redundancy
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