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Comment by renewiltord | Hacker News Reader

I'm sure there have been older tools with this, but Terraform is the first I encountered with it and I really like this model.

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rsync is where I first encountered it. I've made it a habit to always do a dry run first as a sanity check and it has saved me some headaches.

rsync has a plan mode? I had no idea.

-n or --dry-run. Rsync has a TON of features, it is worth the time to thoroughly read the man page at least once

Right, but `--dry-run` is just a dry run mode, right? You have to sort of post-process it to create a plan.

I feel like the context for this comment thread was lost. Just to repeat it to forestall any further discussion in this subthread on non-plan dry-run, this is how I saw it:

* Igor: a good way to do dry run is to make plan

* * Me: first time i have seen 'plan' as explicit step for dry-run is with Terraform

* * * fickle: rsync is where i first encounter it [it here is not plan, it is dry-run]

* * * * me: really? rsync has 'plan'?

* * * * * john: rsync has dry-run. read manpage

i.e. Igor and I are talking about explicit plan (which is interesting model) and you guys are talking about dry-run.

Ah, sorry, I definitely lost that context. Thanks for clarifying

rsync --only-write-batch exactly works as you want. This is another dry-run.

Terraform does frequently suffer from the lack of good separation here though, depending on the provider in question - a plan can often succeed where a subseuqent apply will fail. Too much external state / not enough validation, generally.

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