Brocade Communications Systems ICX 7250 series, Configuration Manual

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Static ARP table
In addition to the ARP cache, Layer 3 switches have a static ARP table. Entries in the static ARP table are user-configured. You can add
entries to the static ARP table regardless of whether or not the device the entry is for is connected to the Layer 3 switch.
NOTE
Layer 3 switches have a static ARP table. Layer 2 switches do not.
The software places an entry from the static ARP table into the ARP cache when the entry interface comes up.
Here is an example of a static ARP entry.
Index IP Address MAC Address Port
1 10.95.6.111 0000.003b.d210 1/1/1
Each entry lists the information you specified when you created the entry.
IP route table
The IP route table contains paths to IP destinations.
NOTE
Layer 2 switches do not have an IP route table. A Layer 2 switch sends all packets addressed to another subnet to the default
gateway, which you specify when you configure the basic IP information on the Layer 2 switch.
The IP route table can receive the paths from the following sources:
• A directly-connected destination, which means there are no router hops to the destination
• A static IP route, which is a user-configured route
• A route learned through RIP
• A route learned through OSPF
• A route learned through BGP4
The IP route table contains the best path to a destination:
• When the software receives paths from more than one of the sources listed above, the software compares the administrative
distance of each path and selects the path with the lowest administrative distance. The administrative distance is a protocol-
independent value from 1 through 255.
• When the software receives two or more best paths from the same source and the paths have the same metric (cost), the
software can load share traffic among the paths based on destination host or network address (based on the configuration and
the Layer 3 switch model).
Here is an example of an entry in the IP route table.
Destination NetMask Gateway Port Cost Type
10.1.0.0 255.255.0.0 10.1.1.2 1/1/1 2 R
Each IP route table entry contains the destination IP address and subnet mask and the IP address of the next-hop router interface to the
destination. Each entry also indicates the port attached to the destination or the next-hop to the destination, the route IP metric (cost), and
the type. The type indicates how the IP route table received the route.
To increase the size of the IP route table for learned and static routes, refer to the section "Displaying and modifying system parameter
default settings" in the
Brocade FastIron Layer 2 Switching Configuration Guide
• For learned routes, modify the ip-route parameter.
• For static routes, modify the ip-static-route parameter.
IP configuration overview
Brocade FastIron Layer 3 Routing Configuration Guide
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