Ethernet
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Ethernet Link Redundancy via Smart-Probing enhances the 2020 SBC’s ability to initiate a switchover due to a failure in the network. Currently the IMG 2020 employs a link based Ethernet Redundancy scheme. In the current scheme, the IMG 2020 would initiate a switch-over such as from interface Data A0 to Data A1 located on the rear of the system. With the addition of this feature the IMG 2020 can be configured to employ a probe-based detection scheme. In this scheme, the IMG 2020 would probe a set of pre-configured endpoints (send an ARP request packet). The endpoints would then reply with a Gratuitous ARP packet. These packets inform the IMG 2020 that the endpoints are still alive. If the IMG 2020 sends out an ARP Request Packet and does not receive a Gratuitous ARP in return it will continue to send ARP Requests until the pre-configured number of requests is met. If at that time no Gratuitous ARP’s are sent back then a switchover to its Hot Standby Port (Data A1 in this case) will be initiated. If the switchover solves the problem, then calls will continue to be processed on the new switched-over port. However, if the issue is not solved, the IMG 2020 would continue to switch back and forth between Data A0 and Data A1 (ping pong effect) until the issue in the network is solved. The feature is enabled through the Web GUI and can be enabled on any of the network interfaces (CTRL, Data A, Data B).
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