Keypoints about High Availability and Fault Tolerance (HAFT) solution
The architecture of HAFT is as follows:
The keypoints about HAFT solution is as follows:
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Use this set up, if the RTO is highly demanding, which ranges from few seconds or minutes.
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Each data center or the cloud region hosts an independent or isolated cluster of its own.
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HAFT solution can be set up using
Hot standby mode or
Active-Active mode. The following table explains the difference between both the modes.
Failover Mode | RTO | RPO | Description |
Hot standby mode | few seconds or minutes (time taken to switch the load balancer). | less than 5 seconds. | ![*](chapterTOC_bullet.png) You can have only two data centers. Out of which, only the primary data center serves the client request. |
Active-Active mode | no down time. | less than 5 seconds. | ![*](chapterTOC_bullet.png) You can have N (Minimum 2) number of data centers and all the data centers serve the client request. |
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API assets should be synchronized across the data center through CI-CD deployments.
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Cross-DC federation support offered by API Gateway is limited to API consumers and auth tokens.
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API transactions are local to the cluster where the traffic is served and not aggregated. For aggregated transactions, use a centralized API Data Store.