[prev in list] [next in list] [prev in thread] [next in thread] 

List:       evms-devel
Subject:    [Evms-devel] (no subject)
From:       "Steve Dobbelstein" <steved () us ! ibm ! com>
Date:       2001-09-20 10:25:02
[Download RAW message or body]

The Engine's name registration code has been changed so that all Engine
objects must have globally unique names.  Prior to this change the Engine
maintained separate name registries by object type (DISK, SEGMENT, REGION,
VOLUME, etc.)

The main reason for this change was to make the command line utilities
easier to use.  Users of the command line specify objects by name.  If
names are only unique by type, then the user has to specify the type of the
object along with the name.  It would be easier to just specify the object
name and have the Engine find the right object.  We didn't see any problem
with making all objects in the Engine have unique names.

To make names unique we have to differentiate between the storage object,
e.g., /dev/evms/hda5, and the volume that is created from that object,
/dev/evms/hda5.  To resolve this name conflict, object names within the
Engine will not have the "/dev/evms/" prefix on them.  In our example, the
segment hda5 will simply be named "hda5".  Volumes names will have the
"/dev/evms/" prefix since that truly is part of the volume name.

The current plug-in APIs for name validation and registration still have an
object_type_t parameter which is now no longer needed.  The Engine ignores
this parameter.  Once the new global name registry code gets some exercise,
the object_type_t parameter will be removed from the validation and
registration APIs and the plug-ins will be updated accordingly.

Steve Dobbelstein

[prev in list] [next in list] [prev in thread] [next in thread]