High Availability Exchange
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Contents
Standby AMC-IP
The AlphaCom E20 and AlphaCom E26 exchanges can be equipped with a second AMC-IP card. Both AMC-IP cards are under control of the APC-card and report failure information to the APC, which for this purpose is equipped with a microcontroller. Based on that information the APC decides if and when to switchover between the 2 AMC-IP cards. This means that in the case of an AMC-IP card failure the down time of an E26 exchange is reduced to the time it takes for the standby AMC-IP card to take over rather than the time to get a new card from stock, program it and install it, which even if the card is an on-site spare, will easily take 30 minutes.
Operation
The supervisor of the system is a microprocessor plugged in on the APC card. The APC processor monitors the two AMC-IP cards by a dedicated I2C bus controlling some dedicated hardware I/O on the AMC-IP card. The two AMC-IP cards must be placed in board position 24 and 25.
Both AMC-IP cards can be configured with the exact same backup.bin database (also same IP adresses).
The active AMC-IP card is switched only when the standby AMC-IP card status is reported OK and the master is setting the "Standby request" flag. <br\>
The standby request flag is set when:
- Hardware reset of the master card (Watch dog)
- Software reset of the master card
- Hot swap cable use on the master card
- If all connections to IP stations are lost after reaching the IP station registration trigger level.
- If the Stentofon Multidrop protocol fails. (This protocol can be active on both active and standby card)
On the AMC-IP in standby mode the Ethernet port 1 is deactivated. This means that Eth1 from both AMC-IP cards can be connected to the same network switch, but only one of them will be operational at a time.
Note: Only Eth1 can be used as 'common' port. Eth0 and the two serial ports are not deactivated on the standby board.
Due to boot of Linux the switch between the AMC-IP cards takes approx 1 min and 30 seconds.
License handling
For systems requiring licenses the following rules applies (Available from AMC 10.51):<br\>
- The AMC-IP in pos 25 must have a legal license
- The AMC-IP in pos 24 does not need to have licenses installed (i.e. Free License)
AMC-IP in pos 24 will have a free license as long as there is a AMC IP board present in pos 25. If no AMC IP is present in board pos 25 the free license timer will start ticking.
Software requirements
- AMC software 10.52 or higher
- Flash image version 16
From factory the AMC-IP board comes with Flash image version 12, so it is required to do a [[AMC_Flash_Image_update|AlphaCom Flash Image Upgrade].
Redundant power supplies
The AlphaCom E26 always has had support for redundant power supplies. This redundancy was supported by the old 1009701000 PSU, and is now supported by the 1009703000. Note that the power supplies operate in load sharing mode which increases the reliability even further, as each PSU is only loaded far below its capability, giving a much lower stress on the compents than for which they are designed.
Note that the redundant AMC-IP solution can also be use in an AlphaCom E20 exchange; this exchange however does not support redundant power supplies.
Ordering information
The components required for the AlphaCom High Availability exchange are available under the following numbers:
- 1009626010: High Availability exchange, dual AMC-IP with automatic switch over and 2 PSU's; additional AMC-IP filter card is included
- 1009626011: E26 High Availability extension package, AMC-IP card (including filtercard) and APC upgrade kit