Platform Redundancy - Avaya 8800 Planning And Engineering

VLACP configuration at the port level is consistent—both sides of the point-to-point
connection should be either enabled or disabled.
• VLACP is configured by port. The port can be either an individual port or a MLT member.
VLACPDUs are sent periodically on each port where VLACP is enabled. This allows the
exchange of VLACPDUs from an end-to-end perspective. If VLACPDUs are not received
on a particular link, that link is taken down after the expiry timeout occurs (timeout scale
x periodic time). This implies that unless VLACP is enabled on the IST peer, the ports
stay in a disabled state. When VLACP is enabled at the IST peer, the VLACPDU is
received and the ports are reenabled. This behavior can be replicated despite the IST
connectivity between the end-to-end peers. When you enable VLACP on the IST ports at
one end of the IST, the ports are taken down along with the IST. However, the IST at the
other end stays active until the expiry timeout occurs on the other end. As soon you enable
VLACP at the other end, the VLACPDU is received by the peer and the ports are brought
up at the software level.

Platform redundancy

Provide platform layer redundancy to ensure that faulty hardware does not cause a service
interruption.
Avaya recommends that you use the following mechanisms to achieve device-level
redundancy:
• Redundant power supplies
Employ N + 1 power supply redundancy, where N is the number of required power
supplies to power the chassis and its modules. Connect the power supplies to an
additional power supply line to protect against supply problems.
To provide additional redundancy, you can use the 8005DI AC power supply, which is a
dual AC input, 1170/1492 watts (W) AC-DC power supply. On the 8005DI AC power
supply, the two AC input sources can be out of synchronization with each other, having
a different voltage, frequency, phase rotation, and phase angle as long as the power
characteristics for each separate input AC source remain within the range of the
manufacturer's specifications.
The 8000 Series switch has two slots for fan trays or cooling modules, each with eight
individual fans. Sensors are used to monitor board health.
• Input/output (I/O) port redundancy
You can protect I/O ports using a link aggregation mechanism. MLT, which is compatible
with 802.3ad static (Link Access Control Protocol [LACP] disabled), provides you with a
load sharing and failover mechanism to protect against module, port, fiber or complete
link failures.
• Switch fabric redundancy
Avaya recommends that you use two SF/CPUs to protect against switch fabric failures.
The two SF/CPUs load share and provide backup for each other. Using the 8006 or 8010
Planning and Engineering — Network Design
Platform redundancy
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