As mentioned earlier, the pathname prefix
/net is the most common name that
lsm-qnet.so uses.
In resolving names in a network-wide pathname space,
the following terms come into play:
- node name
- A character string that identifies the node you're talking to.
Note that a node name can't contain slashes or dots.
In the example above, we used lab2 as one of our node names.
The default is fetched via
confstr()
with the _CS_HOSTNAME parameter.
- node domain
- A character string that's “tacked” onto
the node name by lsm-qnet.so.
Together the node name and node
domain must form a string that's unique for all
nodes that are talking to each other. The default
is fetched via confstr() with the
_CS_DOMAIN parameter.
- fully qualified node name (FQNN)
- The string formed by tacking the node name and node domain together.
For example, if the node name is
lab2 and the node domain name is
qnx.com, the resulting FQNN would be
lab2.qnx.com.
- network directory
- A directory in the pathname space implemented by
lsm-qnet.so.
Each network directory (there can be
more than one on a node) has an associated node domain.
The default is /net, as used in the examples
in this chapter.
- name resolution
- The process by which lsm-qnet.so converts an
FQNN to a list of destination addresses that the transport
layer knows how to get to.
- name resolver
- A piece of code that implements one method of converting
an FQNN to a list of destination addresses. Each network
directory has a list of name resolvers that are applied in
turn to attempt to resolve the FQNN. The default is
en_ionet (see the next section).
- Quality of Service (QoS)
- A definition of connectivity between two nodes.
The default QoS is loadbalance (see the section on
QoS later in this chapter.)