DPA can be specified as an argument with the aspath-option field of the:
Any packets sent to this group of bgp peers will have the DPA in the BGP packet modified to be this DPA value from this AS. The DPA is specified as part of the AS Path optional (aspath-opt) attributes. Other AS Path optional attributes are:
Any packets received with the bgp peer or aspath will also be check for DPA within the bgp packet of this value. The DPA is specified as part of the AS Path optional (aspath-opt) attributes.
group type [internal | external] peeras 185 aspath-opt { dpa [number] } { peer host-addr; }
Examples of this code are:group type internal peeras 185 aspath-opt { dpa 20 } { peer 198.108.60.43; } group type external peeras 65 aspath-opt { dpa 20 } { peer 198.108.60.43; }
import proto bgp as as-id
aspath-opt {
dpa [number]
} [pref [number]]
{
route-filter;
};
Example of this code is:
import proto bgp as 185
aspath-opt
{
dpa 20 as 20;
}
pref 20
{
128.2 restrict;
all;
}
export proto bgp as 2750
{
proto bgp as 2704
aspath-opt {
dpa 10 as 20
}
{
route-filter;
}
}
export proto bgp as 2750
mod-aspath
{
dpa value; # Note AS will be taken from this node
}
{
proto bgp as 2704
{
route-filter;
}
proto bgp aspath any
{
route-filter;
}
};
Each of the DPA statements on import and export will test:
Test preference setting based on AS based on
Adding to route from the following sources