pathalias.1 (2010 09)

p
pathalias(1) pathalias(1)
Some examples:
down princeton!(DEDICATED), tilt,
%thrash(LOCAL)
princeton topaz!(DEMAND+LOW)
topaz @rutgers(LOCAL+1)
If a link is encountered more than once, the least-cost occurrence dictates the cost and network character.
Links are treated as bidirectional but asymmetric: for each link declared in the input, a
DEAD reverse
link is assumed.
If the ‘‘to’’ host in a link is surrounded by angle brackets, the link is considered terminal , and further
links beyond this one are heavily penalized. For example, with input
seismo <research>(10), research(100), ihnp4(10)
research allegra(10)
ihnp4 allegra(50)
the path from seismo to research is direct, but the path from
seismo to allegra uses ihnp4
as a relay; not research.
The set of names by which a host is known by its neighbors is called its aliases . Aliases are declared as
follows:
name
=alias , alias ...
The name used in the route to or through aliased hosts is the name by which the host is known to its
predecessor in the route.
Fully connected networks, such as the
ARPANET
or a local-area network, are declared as follows:
net={host, host, ...}
The host-list can be preceded or followed by a routing character (! by default), and can be followed by a
cost (4000 by default). The network name is optional; if not given, pathalias creates one.
etherhosts = {rahway, milan, joliet}!(LOCAL)
ringhosts = @{gimli, alida, almo}(DEDICATED)
= {etherhosts, ringhosts}(0)
The routing character used in a route to a network member is the one encountered when ‘‘entering’’ the
network. See also the sections on gateways and domains.
Connection data can be given while hiding host names by declaring
private {host, host, ...}
pathalias does not generate routes for private hosts, but can produce routes through them. The scope
of a private declaration extends from the declaration to the end of the input file in which it appears, or to
a private declaration with an empty host list, whichever comes first. The latter scope rule offers a way to
retain the semantics of private declarations when reading from the standard input.
Dead hosts, links, or networks can be presented in the input stream by declaring
dead {arg, ... }
where arg has the same form as the argument to the -d option.
To force a specific cost for a link, delete all prior declarations with
delete {host1 !host2 }
and declare the link as desired. To delete a host and all its links, use
delete {host }
Error diagnostics refer to the file in which the error was found. To alter the file name, use
file {filename }
Fine-tuning is possible by adjusting the weights of all links from a given host, as in
adjust {host1 , host-2 (LOW), host3 (-1)}
If no cost is given, a default of 4000 is used.
2 Hewlett-Packard Company − 2 − HP-UX 11i Version 3: September 2010