Hardware Abstraction Layer And Drivers; Redundancy; Secure Network Time Protocol (Sntp) - Extreme Networks Summit WM3000 Series Reference Manual

or stuck in an endless loop) is detected when its heartbeat is not received. Such a process is terminated
(if still running) and restarted (if configured) by the Process Monitor.

Hardware Abstraction Layer and Drivers

The Hardware Abstraction Layer (
hardware/platform specific data. Drivers include platform specific components such as Ethernet, Flash
Memory storage and thermal sensors.

Redundancy

Using the controller redundancy, up to 12 controllers can be configured in a redundancy group or
cluster (and provide group monitoring). In the event of a controller failure, an existing cluster member
assumes control. Therefore, the controller supported network is always up and running even if a
controller fails or is removed for maintenance or a software upgrade.
The following redundancy features are supported:
Up to 12 controller redundancy members are supported in a single group. Each member is capable
●
of tracking statistics for the entire group in addition to their own.
Each redundancy group is capable of supporting an Active/Active configuration responsible for
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group load sharing.
Members within the same redundancy group can be deployed across different subnets.
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APs are load balanced across members of the group.
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Licenses are aggregated across the group. When a new member joins the group, the new member
●
can leverage the Access Point adoption license(s) of existing members.
Each member of the redundancy group (including the reporting controller) is capable of displaying
●
cluster performance statistics for all members in addition to their own.
Centralized redundancy group management using the controller CLI.
●
For more information on configuring the controller for redundancy support, see
"Configuring Controller Redundancy and Clustering" on page

Secure Network Time Protocol (SNTP)

Secure Network Time Protocol (SNTP) manages time and/or network clock synchronization within the
controller managed network. SNTP is a client/server implementation. The controller (a SNTP client)
periodically synchronizes its clock with a master clock (an NTP server). For example, the controller
resets its clock to 07:04:59 upon reading a time of 07:04:59 from its designated NTP server. Time
synchronization is recommended for the controller's network operations. The following holds true:
The controller can be configured to provide NTP services to NTP clients.
●
The controller can provide NTP support for user authentication.
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Secure Network Time Protocol (SNTP) clients can be configured to synchronize controller time with an
●
external NTP server.
For information on configuring the controller to support SNTP, see
page 259.
Summit WM3000 Series Controller System Reference Guide
HAL)
provides an abstraction library with an interface hiding
270.
"Configuring Secure NTP" on
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