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Routing Management Policy
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precedence, the multiple routes will be adopted. Thus, the router will forward the 
packets to the destination through these paths according to a certain algorithm so 
as to implement load sharing.
For the same destination, a specified routing protocol may find multiple different 
routes with the same precedence and different next hops. If the routing protocol 
has the highest precedence among all active routing protocols, these multiple 
routes will be regarded as currently valid routes. Thus, load sharing of IP traffic is 
ensured in terms of routing protocols.
By far, Switch 8800 Family series support eight routes to implement load sharing.
Route backup
The Switch 8800 Family series support route backup. When the main route fails, 
the system will automatically switch to a backup route to improve the network 
reliability.
In order to achieve static route backup, the user can configure multiple routes to 
the same destination according to actual situations. One of the routes has the 
highest precedence and is called as main route. The other routes have descending 
precedence levels and are called as backup routes. Normally, the router sends data 
via main route. When the line fails, the main route will hide itself and the router 
will choose one from the left routes as a backup route whose precedence is higher 
than others’ to send data. In this way, the switchover from the main route to the 
backup route is implemented. When the main route recovers, the router will 
restore it and re-select route. As the main route has the highest precedence, the 
router still chooses the main route to send data. This process is the automatic 
switchover from the backup route to the main route.
Routes Shared Between 
Routing Protocols
As the algorithms of various routing protocols are different, different protocols 
may generate different routes, thus bringing about the problem of how to resolve 
the differences when different routes are generated by different routing protocols. 
The Switch 8800 Family series support the import of routes discovered by one 
routing protocol into another. Each protocol has its own route importing 
mechanism. For details, refer to the description about "Importing an External 
Route" in the operation manual of the corresponding routing protocol.