What is DAC and how dac process work at backend?

What is DAC and how dac process work at backend?
ELS ELSAsked:
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AmitIT ArchitectCommented:
I guess you know why it is needed. If not, it is required to avoid split brain syndrome. You might have read it. Say your have Exchange DAG on two sites. Site1 and Site 2. Assume Site 1 goes down due to power outage, your WAN also goes down and you make Site 2 active by using alternate FSW. Now you fixed power issue on Site1 and server come back up, however your network still not fully up. In this case to avoid Site1 mounting its DB. DAC mode is enabled. When you enable it, DACP bit value is set to zero, in your site 1. Site 2 will have One value. Once your Site1 is able to restore connection with Site 2 Servers. Now you will be allowed to mount db in site 1 again.

Let me know, if that clears your doubt.

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