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Comment by dwedge | Hacker News Reader

At $dayjob we have the same mentality and as a result have a load of managed read replicas that are never used for anything (not reporting, not read only queries, not backups because $cloud handles it) that cost every month. Plus managed database restricts what you can do with the database - sometimes in really annoying ways.

So while I partly agree with you, a lot of companies don't really need HA, read replicas, or even PITR (though I would argue the last one is so trivial and cheap to enable that why not), but they click the expensive check box, and I would argue that companies who do need these features should consider hiring at least a couple of DBAs and get more flexibility instead of the current status quo of everyone being scared of the database and everyone just hoping cloud support will come to their rescue if ever needed

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> hiring at least a couple of DBAs and get more flexibility

Every place I’ve ever worked at that had DBAs had the complete opposite of more flexibility. You have to do things the DBA’s way, and if their way doesn’t work for your service, you need to fight for their time and priority.

Meanwhile every place I worked at where every team completely owned their databases + did periodic data recovery drills had much more flexibility and no data loss.

That’s usually because they’ve seen a lot of failure modes over the years, and what seems fine to you can have surprising outcomes later.

My personal experience has been the opposite of yours: lots of data inconsistency issues, data loss only resolved by the database team spinning up backups, etc. And somehow, even after yet another incident, there’s never been appetite to properly fix things.

Now you have lots of DBs all probably operating inefficiently with only periodic recovery testing. This is the stuff DBAs do every day, and you're "hasn't happened to us... yet". You'll be just another lesson someday

Are you saying DBAs would be doing _continuous_ recovery testing? That’s not even a thing that exists.

Managed databases don’t lose customer data. They would be sued and lose, and if word got out, they would lose their customers. They are optimized for the machines they run on. The proprietary tooling from AWS for managing HA clusters, doing blue-green upgrades and monitoring for slow queries is all miles ahead of the open source tooling available for self-managed databases.

There’s nothing left for the DBA to do.

> There’s nothing left for the DBA to do.

And yet here we still are

DBAs in orgs who resource their data teams indeed do constant validation of recovery. I know many DBAs who are in more demand than ever due to the rise of managed databases. If you don't need a DBA, you aren't at a scale or maturity just yet. That you're so dismissive of this role, I have to dismiss your entire opinion because you simply don't grasp the scale of large databases

>constant validation of recovery

So the same thing I said we do, a periodic validation of recovery, but with an acceptably short period.

SWEs can do that too. They can even write software to do most of it automatically.

They went through systems design interviews to ensure they know how to scale without picking technology choices that require a dedicated human caretaker.

It’s the opposite. Needing a DBA to operate a completely managed database is a sign of not enough maturity.

DBAs write software to do this too. You think DBAs are just clicking around in some gui? Hate to break it to you, but every field has done leaps and bounds over the decades too. SWEs can certainly "learn the trade" as a DBA can "learn to code" their own tooling as well, but you realize people specialize, there's fields of practice and domain experts. One of the greatest inventions is the division of labor and specialization.

> At $dayjob we have the same mentality and as a result have a load of managed read replicas that are never used for anything (not reporting, not read only queries, not backups because $cloud handles it) that cost every month.

Obviously "let RDS manage your database" doesn't require egregious read replicas. The decision to use read replicas or not is completely orthogonal to whether you use RDS to manage them.

> Obviously "let RDS manage your database" doesn't require egregious read replicas

Of course not, but an easy checkbox, a best practice AWS or terraform guide and someone doing AWS certified X associate makes it easier to happen without anyone ever really discussing it.

> The decision to use read replicas or not is completely orthogonal to whether you use RDS to manage them.

Assuming you're talking about letting RDS manage anything, then sure - apart from it being more likely to slip through the net if nobody has to configure them. Database is just an expensive cost nobody necessarily drills into.

However if you mean the decision to let $cloud manage the replicas (and keep the primary managed), that totally depends on the cloud and the options. For example have you ever tried having a primary in GCP Cloud SQL but the replica not in cloud SQL?

> Of course not, but an easy checkbox, a best practice AWS or terraform guide and someone doing AWS certified X associate makes it easier to happen without anyone ever really discussing it.

I'm defending your employer or their mindset, I'm just disagreeing with your claim that this follows from the parent's cost analysis claims. It _seems_ like your organization's problems are precisely because they _weren't_ doing the kind of cost analysis that the parent advocated. In other words, nothing in the parent's comment advocated for blindly following some Terraform guide. It feels unfair to the parent to suggest that their mindset caused your organization problems when it seems like your organization's problems were caused by _not having_ the parent's mindset.

They won't let you. It's part of their business to keep you locked in.

More likely it’s just not worth going out of their way to support niche deployments like that. I’ve been using various clouds for years, I’ve done half a dozen cloud migrations, currently working at a multicloud org—the vendors aren’t doing much to lock us in. They very much enable us to move platforms by offering things like bulk data transfer tools, standard application runtimes like Kubernetes, workload identity federation (use external identities as principals in the cloud provider’s IAM system, etc).

Like I have no doubt that they’re all greedy bastards, but they aren’t doing much to lock people in. The people who complain about lock in are usually talking about “cloud providers making their services so much easier to use than bespoke platforms on bare Linux hosts such that no one will want to go back to the latter”.

> Like I have no doubt that they’re all greedy bastards, but they aren’t doing much to lock people in.

A few years ago we were trying to do a live migration from on-prem into GCP (mostly to have GCP as a failover option but move everything there if on-prem went down). We configured an async GCP slave from the on-prem cluster and once running it was easy. Multi-TB migration straight into CloudSQL with seconds of downtime.

Before we signed this off, we also tested the reverse - getting back from CloudSQL into on-prem. Turns out you couldn't (at the time, I'm not sure about currently) use CloudSQL as master for an external slave, only a slave to an external master. You could migrate the data in with no downtime, to get it back out was a multi-TB transfer. The door only opens one way.

So no, I am talking about lock in.

A company not going out of their way to make it expedient for you to transition off of their cloud isn’t “lock in”.

You can use RDS without HA. Many people probably should do this, but no one wants to tell their boss they want to disable RDS HA and wear 1h of downtime a year so they can cut 50% of their spend.

> no one wants to tell their boss they want to disable RDS HA and wear 1h of downtime a year so they can cut 50% of their spend.

If you're a SaaS, 1h of downtime costs a lot of money. In reputation, in lost business, in support time, in on-call response, in making a public postmortem and sharing it to customers and dealing with responses... For saving a few thousand bucks, it's often indeed a very bad deal.

Most of those are already priced in (support costs, time dealing with a postmortem), and an hour of downtime a year isn't going to meaningfully harm the reputation of most companies, I'd wager a lot of clients wouldn't even notice.

Of course this isn't true for some companies and the cost of downtime far exceeds the cost of HA. Most companies think they are that company, most aren't. And even if they are, "AWS had an outage" does a lot of lifting.

Every time I get a new client they need constant point in time backups, failover, HA everything. Usually when the costs are explained they change their mind and an hour old snapshot restore is actually fine

That's really helpful. Thanks!

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