Do Amazon High I/O instance guarantee disk persistence? -


the high i/o instance in ec2 uses ssd. how 1 run database on such instance while guaranteeing persistance of data?

from limited understanding, i'm suppose use elastic block store (ebs) if machine goes down data on disk doesn't disappear. on other hand instance storage ssd of high i/o instance ephemeral , can't used database storage because if, example, machine loses power data image isn't preserved. understanding correct?

point 1) if workloads need high io ssd db, should have master slave setup. ideally 1 master , 2 slaves spread across 3 az's suggested. if there outage on single az alternate az's can handle load , serve high availability needs. between master - slave can employ synchronous, semi or async replication depending upon db. solution costlier.

point 2) if db oltp in nature, amazon ebs piops + ebs optimized gives consistent iops. single ebs volume can provide 4000 iops , can raid 0 multiple volumes , gain 10k+ iops performance. lots of customers taking route in aws. though may use ebs persistence, still recommended go master-slave architecture high availability. have written detailed articles on topic in blog, refer them more information.


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