SGS-6341-Series User Manual

 Second, ensure the interface and chain protoco
l are UP (use show interface
command)
 Then initiate the RIP protocol (use router rip command) and configure the segment
(use network command) and set RIP protocol parameter on corresponding interfaces,
such as the option between RIP-I and RIP-II
 After that, one feature of RIP protocol should be noticed ---the Layer 3 switch running
RIP protocol sending route updating messages to all neighboring Layer 3 switches
every 30 seconds. A Layer 3 switch is considered inaccessible if no route updating
messages from the switch is received within 180 seconds, then the route to the switch
will remains in the route table for 120 seconds before it is deleted. Therefore, if to delete
a RIP route, this route item is assured to be deleted from route table after 300 seconds.
 When exchanging routing messages with CE using RIP protocol on the PE router, we
should first create corresponding VPN routing/transmitting examples to associate with
corresponding interfaces. Then enter the RIP address family mode configuring
corresponding parameters. If the RIP routing problem remains unresolved, please use
debug rip command to record the debug message in three minutes, and send them to
our technical service center.
26.5 OSPF
26.5.1 Introduction to OSPF
OSPF is abbreviation for Open Shortest Path First. It is an interior dynamic routing protocol for
autonomous system based on link-state. The protocol creates a link-state database by
exchanging link-states among Layer 3 switches, and then uses the Shortest Path First
algorithm to generate a route table basing on that database.
Autonomous system (AS) is a self-managed interconnected network. In large networks, such
as the Internet, a giant interconnected network is broken down to autonomous systems. Big
enterprise networks connecting to the Internet are independent AS, since the other hosts on
the Internet are not managed by those AS and they don’t share interior routing information with
the Layer 3 switches on the Internet.
Each link-state Layer 3 switch can provide information about the topology with its neighboring
Layer 3 switches.
• The network segment (link) connecting to the Layer 3 switch
• State of the connecting link
Link-state information is flooded throughout the network so that all Layer 3 switches can get
firsthand information. Link-state Layer 3 switches will not broadcast all information contained in
their route tables; instead, they only send changed link-state information. Link-state Layer 3
switches establish neighborhood by sending “HELLO” to their neighbors, then link-state
advertisements (LSA) will be sent among neighboring Layer 3 switches. Neighboring Layer 3
switch copy the LSA to their routing table and transfer the information to the rest part of the
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User’s Manual of SGS-6341 series