sql server - Large Scale Distributed Application in AWS / Azure -

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i working on large scale web app users can anywhere in world.

considerations: 1. web servers needs distributed in possibly 3 data centers possibly across 3 continents. 2. each datacenter might have 2 webservers (asp.net) start , can scale out 3. database needs partitioned (sql server sherding). not thinking of separate database instances , mirroring 4. application have media contents. so, cdn might right fit them.

hosting options: 1. azure/aws iaas: in case web , applciation servers needs configured , managed 2. azure/aws paas: here tied using vendor specific tools, code blocks , "way of doing things" , 1 fine morning announce retiring dependant service (eg. sql azure federation). also, consider limits around db max size 150gb az sql , throttling within shared services.

so, hosting option 1 looks safe bet around.

now questions:

  1. i need consider load balancing server each data center route traffic 2 or more web servers in data center. managing traffic anywhere of world come desired data centers? in iaas model, put load balancer distributes web traffic across datacenters?
  2. i came across azure traffic manager seems take care of problem 1 above, work iaas offering? equivalent in aws? desired when user connects apac, redirected dc in asia.
  3. in sherding model, want partition specific database tables , not all. not quite familiar, how failover work in sherded database? can have active passive sql servers each member database server in federation? (btw sql federation same sherding?)

the application asp.net , sql server based.

max size 1 terabyte sql azure - see https://azure.microsoft.com/en-us/pricing/details/sql-database/ , @ premium tier...


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