HP-UX TCP/IP Performance White Paper, March 2008

ip_ipif_status:

Display a report of all allocated logical interfaces.

A logical interface is created whenever one adds IP addresses to the one already assigned to a "physical"

interface. These are also sometimes referred to as aliased addresses and are given names such as lan0:1,

lan0:2 and so on. These exist only in the "mind" of IP. Neither the NIC driver nor DLPI knows of its

existence. While a physical/virtual interface (see the discussion of ip_ill_status) will appear in the

output of lanscan(1m), a logical interface will not.

It is possible to have a virtual interface created with Auto Port Aggregation treated by IP as a physical

interface on which there are several, additional, logical interfaces. In the future, that "virtual" interface

could be a VLAN operating of the same APA aggregate.

ip_ire_hash:

Display a report of all routing table entries, in the order

searched when resolving an IP address.

The Internet Routing Entry (IRE) is the primary data structure that links IP addresses with particular interfaces,

attached networks, gateways, and local and remote hosts. The corresponding data structure for IPv6 is an

IRE6.

ip_ire_status:

Display a report of all routing table entries. Same

information as in ip_ire_hash, but format and ordering are

different.

ip_ire_cleanup_interval:

Sets the time-out interval for purging routing table entries.

All entries unused for this period of time are deleted.

[5000, - ] Default: 300000 (5 minutes)

ip_ire_flush_interval:

All routing table entries are deleted after this amount

of time; even those which have been recently used. [60000, -]

Default: 1200000 (20 minutes)

Host routes associated with the IRE_ROUTE flag from the ndd –get /dev/ip ip_ire_status output

will be deleted. A host route with the IRE_ROUTE flag must exist for any non-local destination before an IP

datagram can be sent to that address. The IRE_ROUTE host routes are created internally in IP for all non-

local destinations to improve routing lookup. None of the routes from the netstat –rn output will be

deleted.

ip_ire_gw_probe:

Enable dead gateway probes. This option should only be disabled on

networks containing gateways which do not respond to ICMP echo

requests (ping). [0-1] Default: 1 (probe for dead gateways)