NAME
dat.conf - configuration file for static registration of user-level DAT
rdma providers
DESCRIPTION
The DAT (direct access transport) architecture supports the use of
multiple DAT providers within a single consumer application. Consumers
implicitly select a provider using the Interface Adapter name parameter
passed to dat_ia_open().
The subsystem that maps Interface Adapter names to provider
implementations is known as the DAT registry. When a consumer calls
dat_ia_open(), the appropriate provider is found and notified of the
consumer’s request to access the IA. After this point, all DAT API
calls acting on DAT objects are automatically directed to the
appropriate provider entry points.
A persistent, administratively configurable database is used to store
mappings from IA names to provider information. This provider
information includes: the file system path to the provider library
object, version information, and thread safety information. The
location and format of the registry is platform dependent. This
database is known as the Static Registry (SR) and is provided via
entries in the dat.conf file. The process of adding a provider entry is
termed Static Registration.
Registry File Format
* All characters after # on a line are ignored (comments).
* Lines on which there are no characters other than whitespace
and comments are considered blank lines and are ignored.
* Non-blank lines must have seven whitespace separated fields.
These fields may contain whitespace if the field is quoted
with double quotes. Within fields quoated with double quotes,
the backslash or qoute are valid escape sequences:
* Each non-blank line will contain the following fields:
- The IA Name.
- The API version of the library:
[k|u]major.minor where "major" and "minor" are both integers
in decimal format. User-level examples: "u1.2", and "u2.0".
- Whether the library is thread-safe:
[threadsafe|nonthreadsafe]
- Whether this is the default section: [default|nondefault]
- The library image, version included, to be loaded.
- The vendor id and version of DAPL provider: id.major.minor
- ia params, IA specific parameters - device name and port
- platform params, (not used)
Example netdev entries for OpenFabrics rdma_cm providers, both v1.2 and v2.0
OpenIB-cma u1.2 nonthreadsafe default libdaplcma.so.1 dapl.1.2
"ib0 0" ""
ofa-v2-ib0 u2.0 nonthreadsafe default libdaplofa.so.2 dapl.2.0
"ib0 0" ""
NOTE: The OpenFabrics providers use <ia_params> to specify the
device with one of the following:
network address, network hostname, or netdev name; along
with port number.
The OpenIB- and ofa-v2- IA names are unique mappings.
Reserved for OpenFabrics providers.
The default location for this configuration file is /etc/dat.conf. The
file location may be overridden with the environment variable
DAT_OVERRIDE=/your_own_directory/your_dat.conf.
SEE ALSO
25 March 2008