AudioCodes Mediant 3000, User Manual

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User's Manual 116 Document #: LTRT-89729
Mediant 3000
the Ethernet interface fails after the selection is made, the device does not switch over to
the second port.
After start-up is complete and the operational software is running, the device continues to
use the Ethernet port used for software upload. The device switches over from one
Ethernet port to the other each time an Ethernet link carrier-loss is detected on the active
Ethernet port, and if the Ethernet link of the other port is operational. Switchover occurs
only once per link loss (i.e., the ‘secondary’ interface stays the active one even if the
‘primary’ interface has returned to life). After start-up, the device generates a gratuitous
ARP message each time a switchover occurs.
For correct functionality of the redundancy mechanism, it's recommended to configure both
links to the same mode. It is essential that both link partners (primary and secondary) have
the same capabilities. This ensures that whenever a switchover occurs, the device is able
to provide at least the same Ethernet services as were provided prior to the switchover. In
addition, it's recommended to set the physical secondary link prior to resetting the device
(since the MAC configuration cannot be changed thereafter).
Note that since the two Ethernet ports use the same MAC address, the external switches
connected to the device can in some cases create a noticeable switchover delay due to
their internal switching logic, though at the device level, the switchover delay is minimal
(milliseconds).
11.3 Configuring IP Network Interfaces
You can configure a single VoIP network interface for all applications, which includes
OAMP (management traffic), call control (SIP messages), and media (RTP traffic), or you
can configure multiple logical, IP network interfaces for these applications. A need often
arises to have logically separated network segments for these applications for
administration and security. This can be achieved by employing Layer-2 VLANs and Layer-
3 subnets.
The figure below illustrates a typical network architecture where the device is configured
with three network interfaces for the OAMP, call control, and media applications. The
device is connected to a VLAN-aware switch for directing traffic from and to the device to
the three separated Layer-3 broadcast domains according to VLAN tags (middle pane).
Figure 11-1: Multiple Network Interfaces