OmniSwitch os6900, Network Configuration Manual, Page: 351 / 942

Configuring IP IP Configuration
OmniSwitch AOS Release 7 Network Configuration Guide June 2013 page 15-17
Configuring the Time-to-Live (TTL) Value
The TTL value is the default value inserted into the TTL field of the IP header of datagrams originating
from the switch whenever a TTL value is not supplied by the transport layer protocol. The value is
measured in hops.
Use the ip default-ttl command to set the TTL value. Enter the command, followed by the TTL value. For
example, to set a TTL value of 75, you would enter:
-> ip default-ttl 75
The default hop count is 64. The valid range is 1 to 255. Use the show ip config command to display the
default TTL value.
Configuring Route Map Redistribution
You can learn and advertise IPv4 routes between different protocols. Such a process is referred to as route
redistribution and is configured using the
ip redist command.
Redistribution uses route maps to control how external routes are learned and distributed. A route map
consists of one or more user-defined statements that can determine which routes are allowed or denied
access to the receiving network. In addition, a route map can also contain statements that modify route
parameters before they are redistributed.
When a route map is created, a name is given to identify the group of statements that it represents. This
name is required by the
ip redist command. Therefore, configuring route redistribution involves the
following steps:
1
Create a route map, as described in “Using Route Maps” on page 15-17 .
2
Configure redistribution to apply a route map, as described in “Configuring Route Map Redistribu-
tion” on page 15-21 .
Using Route Maps
A route map specifies the criteria that are used to control redistribution of routes between protocols. Such
criteria is defined by configuring route map statements. There are three different types of statements:
•
Action . An action statement configures the route map name, sequence number, and whether
redistribution is permitted or denied based on route map criteria.
•
Match. A match statement specifies criteria that a route must match. When a match occurs, then the
action statement is applied to the route.
•
Set. A set statement is used to modify route information before the route is redistributed into the
receiving protocol. This statement is only applied if all the criteria of the route map is met and the
action permits redistribution.