HP-UX Routing Services Administrator's Guide HP-UX 11i v2, HP-UX 11i v3 (B2355-91153, November 2011)

You can specify the cost clause optionally to define a cost of sending a packet on the interface.
This cost is advertised as the link cost for this interface. See “Cost” (page 38) for more information
on setting interface costs.
You can also enable or disable the interface definition. If you do not explicitly specify disable,
an interface definition is enabled by default.
OSPF supports the following types of network interfaces:
• A multicast (or broadcast) network is a network that supports two or more attached routers
and allows a single message to be addressed to a set of network nodes at the same time. An
example of a multicast network is an Ethernet LAN.
• A non-broadcast multi-access (NBMA) network is a network that supports multiple attached
routers, but does not support broadcasting of messages. An example of an NBMA network
is an X.25 PDN.
• A point-to-point network is a network that joins a single pair of routers. An example of a
point-to-point network is a 56-KB serial line.
The following sections describe each type of interface.
Multicast Interfaces
On multicast networks, an OSPF router dynamically detects its neighbor routers through the OSPF
Hello message. The following statements are defined for a multicast interface:
• retransmitinterval is the number of seconds between retransmission of link states,
database descriptions, and link state request packets. This value must exceed the expected
round-trip delay between any two routers in the network. A sample value for a LAN is 5
seconds.
◦ Default: None (you must specify a value)
◦ Range: Integer between 0 – 65535
• transitdelay is the number of seconds to transmit a Link State Update Packet over this
interface. This value must take into account the transmission and propagation delays for the
interface. It must be greater than 0. A sample value for a LAN is 1 second.
◦ Default: None (you must specify a value)
◦ Range: Integer between 1 – 65535
• priority specifies the priority of the router to be the designated router. You must configure
this value only for interfaces to multi-access networks. This value specifies the priority of the
router to be the designated router. When two routers attached to a network attempt to be the
designated router, the one with the higher router priority value takes precedence.
◦ Default: None (you must specify a value for multi-access networks)
◦ Range: 8-bit unsigned integer between 0 – 255. 0 means that the router is ineligible to
become a designated router on the attached network.
• hellointerval specifies the time interval (in seconds) for the transmission of OSPF Hello
packets. Smaller intervals ensure that changes in network topology are detected faster. A
sample value for an X.25 network is 30 seconds. A sample value for a LAN is 10 seconds.
◦ Default: None (you must specify a value)
◦ Range: Integer between 0 – 255
NOTE: The hellointerval value must be the same for all OSPF routers.
32 Configuring gated