Citrix NetScaler EE, Руководство по установке и настройке

Страница: 331 / 1026

© 1999-2017 Citrix Systems, Inc. All rights reserved. p.331 https://docs.citrix.com
OSPF
Dec 27, 2016
OSPF running on t he LAN port of Net scaler SD-WAN appliance deployed in Gat eway Mode OSPF running on t he LAN port of Net scaler SD-WAN appliance deployed in Gat eway Mode
SD-WAN appliances perform route discovery of Layer 3 routing advertisements within a local customer network (both
branch and data center) for each of the desired routing protocols (OSPF and BGP). The routes that are learnt are
dynamically captured and displayed.
This eliminates the need for SD-WAN administrators to statically define the LAN-side networking environment for each
appliance that is part of the SD-WAN network.
Net Scaler SD-WAN appliance having an AREA defined as a ST UB area by limit ing t he learning of Type 5 AS- Net Scaler SD-WAN appliance having an AREA defined as a ST UB area by limit ing t he learning of Type 5 AS-
ext ernal LSA. ext ernal LSA.
SD-WAN appliances can advertise the locally learned dynamic routes with the MCN. The MCN can then relay these routes
to other SD-WAN appliances in the network. This exchange of information dynamically allows for maintaining connectivity
between sites across the changing network.
In previous releases, OSPF instance learned routes from SD-WAN were treated as external routes with Type 5 LSA only.
These routes were advertised to its neighbor routers in Type 5 External LSA. This resulted in SD-WAN routes to be less
preferred routes according to the OSPF path selection algorithm.
With the latest release, SD-WAN can now advertise routes as intra-area routes (LSA Type 1) to get preference as per its
route cost using the OSPF path selection algorithm. The route cost can be configured and advertised to the neighbor
router. This allows for deploying SD-WAN appliance in one-arm mode described below.
Implementing OSPF in One-Arm Topology
In one-arm configuration, the router needs complicated PBR or WCCP configuration in OSPF deployments. By changing the
default export route type from Type 5 to Type 1 we can simplify this deployment. If SD-WAN routes are advertized as
intra-area routes with less cost, and the SD-WAN appliance becomes active, the neighbor router selects SD-WAN routes
and automatically begins forwarding traffic through SD-WAN network. Additional PBR or WCCP configuration is not
required any longer.
Prerequisit es: Prerequisit es: