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by danmaz74 656 days ago
Having at least 2 web servers and a read-only DB replica for redundancy/high availability is very easy and much safer. Yes, setting up a single-server is faster, but if your DB server dies - and at some point it will happen - you'll not just save a lot of downtime, but also a lot of stress and additional work.
2 comments
brightball 656 days ago
Read replicas come with their own complexity as you have to account for the lag time on the replica for UX. This leads to a lot of unexpected quirks if it’s not planned for.
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danmaz74 656 days ago
That's true, but you can use your replica only for non-realtime reporting, or even just as a hot standby.

Edit: Careful for the non-realtime reporting though if you want to run very slow queries - those will pause replication and can be a PITA.

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cqqxo4zV46cp 656 days ago
A hot standby / failover still meets this definition. That’s how I interpreted what was being described.
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cultofmetatron 655 days ago
my startup has a similar setup (elixir + postgres). we use aurora so we get automated failover. its more expensive but its just a cost of doing business.
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aledalgrande 654 days ago
Last time I looked at Aurora (just as it came out) it was hilariously expensive. Are the costs better now for a real use case?
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cultofmetatron 653 days ago
> it was hilariously expensive

It still is. But you have to look at it in perspective. do you have customers that NEED high availability an will pull out pitch forks if you are down for even a few minutes? I do. the peace of mind is what you're paying for in that case.

Plus its still cheaper than paying a devops guy a fulltime salary to maintain these systems if you do it on your own.

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