Novell OPEN ENTERPRISE SERVER 2 SP2 - ADMINISTRATION, Руководство по внедрению, Страница: 114 / 288

114 OES 2 SP2: Planning and Implementation Guide
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OES 2: On the other hand, for OES 2 services to work, the server must either:
Š
Have an eDirectory replica installed.
This is not automatic after the third server installed in a tree, nor is having more than three to
five replicas on servers in the tree recommended.
Š Have eDirectory registered with the OpenSLP service running on the server.
This requires SLP configuration either during the OES 2 installation or manually.
12.5.2 Comparing Novell SLP and OpenSLP
Table 12-4
SLP Solutions
Platform NetWare OES 2
SLP Solution Novell SLP OpenSLP
About the
Solution The Novell version of SLP adapted
portions of the SLP standard to provide a
more robust service advertising
environment.
Novell SLP remains the default discovery
mechanism for NetWare 6.5 SP8 servers.
However, all NetWare service
components that engage in discovery,
including Novell Client
TM software, can
use alternative mechanisms such as
DNS, eDirectory, or local host
configuration files.
OpenSLP is an implementation of various
IETF specifications, including RFC 2614
(SLP version 2.0). It is the default SLP
service installed on SLES 10.
In OES 2, OpenSLP is available for those
applications that require it. The default
discovery mechanism is actually DNS, but
SLP must be present for any applications
that require it, especially in those cases
where the OES 2 server is the fourth or
later server added to a tree and doesn’t
have an eDirectory replica automatically
installed.
Differences Novell SLP directory agents (DAs) store
service registrations for their SLP scope
in eDirectory.
As a new service registration is stored in
eDirectory, other DAs assigned to the
same scope are notified so that they can
refresh their caches with the latest
service information.
Also, when a Novell SLP DA starts up, it
immediately populates its cache with the
latest service information stored in
eDirectory.
NOTE: Novell SLP DAs do not directly
share information with each other as
many administrators have assumed. But
they do maintain well synchronized
caches through eDirectory as described
above.
OpenSLP directory agents (DAs) are
completely separate and have no way to
initially populate or refresh their service
information the way Novell SLP DAs do.
A DA’s cache is empty when it starts up and
is populated only as services register
themselves.