Graceful Restart Mechanism For Several Commonly Used Protocols - 3Com Switch 4800G 24-Port Configuration Manual

250 C 25: GR O
HAPTER
Graceful Restart
Mechanism for
Several Commonly
Used Protocols
VERVIEW
Figure 67 The GR Restarter obtains topology and routing information from the GR Helper
Router A
Router B
GR helper
As illustrated in Figure 67, the GR Restarter obtains the necessary topology and
routing information from all its neighbors through the GR sessions between them
and calculates its own routing table based on this information.
The switch supports Graceful Restart based on Boarder Gateway Protocol (BGP),
Open Shortest Path First (OSPF), and Intermediate System to Intermediate System
(IS-IS).
For the implementation and configuration procedure of the Graceful Restart
mechanism of the above protocols, refer to "BGP Configuration" on page 365,
"OSPF Configuration" on page 273, and "IS-IS Configuration" on page 325.
Router D
GR helper
GR restarter
Router C
GR helper
Signals to establish GR session