Bgp And Other Vendor Interoperability; Bgp Design Examples - Avaya 8800 Planning And Engineering

If OSPF is the IGP, use the default OSPF tag construction. The use of EGP or the modification
of the OSPF tags makes network administration and proper configuration of BGP path
attributes difficult.
For routers that support both BGP and OSPF, you must set the OSPF router ID and the BGP
identifier to the same IP address. The BGP router ID automatically uses the OSPF router ID.
In configurations where BGP speakers reside on routers that have multiple network
connections over multiple IP interfaces (the typical case for IBGP speakers), consider using
the address of the circuitless (virtual) IP interface as the local peer address. In this way, you
ensure that BGP is reachable as long as an active circuit exists on the router.
By default, BGP speakers do not advertise or inject routes into their IGP. You must configure
route policies to enable route advertisement.
Coordinate routing policies among all BGP speakers within an AS so that every BGP border
router within an AS constructs the same path attributes for an external path.
Configure accept and announce policies on all IBGP connections to accept and propagate all
routes. Make consistent routing policy decisions on external BGP connections.
You cannot enable or disable the Multi-Exit Discriminator selection process. You cannot disable
the aggregation when routes have different MEDs (MULTI_EXIT_DISC) or NEXT_HOP.

BGP and other vendor interoperability

BGP interoperability has been successfully demonstrated between the Avaya Ethernet Routing
Switch 8800/8600 and products from other vendors, including Cisco and Juniper.
For more information about BGP and BGP commands, see Avaya Ethernet Routing Switch
8800/8600 Configuration — BGP Services, NN46205-510. For configuration examples, see
Border Gateway Protocol (BGP-4) Technical Configuration Guide, NN48500-538.

BGP design examples

The following design examples describe typical Avaya Ethernet Routing Switch 8800/8600
BGP applications.
BGP and Internet peering
By using BGP, you can perform Internet peering directly between the Avaya Ethernet Routing
Switch 8800/8600 and another edge router. In such a scenario, you can use each Avaya
Ethernet Routing Switch 8800/8600 for aggregation and peer it with a Layer 3 edge router, as
shown in the following figure.
Planning and Engineering — Network Design
Border Gateway Protocol
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