12: Routing Fundamentals

• View routing tables, configure static routing & OSPF

There are multiple routing tables - inet.0 to inet.4, mpls.0, inet6.0

show route forwarding-table

show route instance

The ‘master’ routing instance is the primary instance.

edit routing-instances <instance-name>
set instance-type ?
    forwarding
    l2vpn
    vpls
    vrf

edit routing-instance <new-instance>
instance-type ???
interface ???

Reference the routing instance name when viewing information (e.g. show commands) or sourcing traffic (e.g. ping, traceroute commands).

The ‘no-readvertise’ option stops Junos redistributing the static route into dynamic routing protocols. It is recommended that this be added to the management interface.

edit routing-options
static {
    route 0.0.0.0/0 next-hop ...;
    route .../24 {
        next-hop ...;
        no-readvertise;
    }
}

Floating static routes can be added using ‘qualified-next-hop’.

OSPF

This topic is covered in more detail in JIR modules 6 and 8.

show ospf neighbor

Use ‘passive’ to prevent forming of adjacencies while continuing to advertise that interface’s subnet.

edit protocols ospf
area 0.0.0.0 {
    interface ... {
        passive;
    }
}

IPv6

set family ipv6 address ...;

The IPv6 routing table (inet6.0) must be specified when configuring IPv6 static routes. A link-local address may be specified as the next-hop, but in this case the outgoing interface must also be specified.

edit routing-options
rib inet6.0 {
    static {
    ...
    }
}