Populating The Routing Table; Dynamic Routes - Extreme Networks BlackDiamond 6800 User Manual

P
OPULATING THE
The BlackDiamond maintains an IP routing table for both network routes and host
routes. The table is populated from the following sources:
• Dynamically, by way of routing protocol packets or ICMP redirects exchanged with
other routers
• Statically, by way of routes entered by the administrator
— Default routes, configured by the administrator
— Locally, by way of interface addresses assigned to the system
— By other static routes, as configured by the administrator
If you define a default route, and subsequently delete the VLAN on the subnet
associated with the default route, the invalid default route entry remains. You
must manually delete the configured default route.
D
YNAMIC
Dynamic routes are typically learned by way of RIP or OSPF. Routers that use RIP or
OSPF exchange information in their routing tables in the form of advertisements. Using
dynamic routes, the routing table contains only networks that are reachable.
Dynamic routes are aged out of the table when an update for the network is not
received for a period of time, as determined by the routing protocol.
S R
TATIC OUTES
Static routes are manually entered into the routing table. Static routes are used to reach
networks not advertised by routers. You can configure up to 64 static unicast routes on
the BlackDiamond.
Static routes can also be used for security reasons, to control which routes you want
advertised by the router. You can decide if you want all static routes to be advertised,
using one of the following commands:
[enable | disable] rip export static
[enable | disable] ospf export static
The default setting is enabled. Static routes are never aged out of the routing table.
B D U G
LACK IAMOND SER UIDE
R
OUTING
R
OUTES
T
ABLE
O IP U R
VERVIEW OF NICAST OUTING
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