21:I[64418,["2399","static/chunks/53c0104b-0bf61919c7da6d97.js","8500","static/chunks/8500-2f0b37d47b98252b.js","8815","static/chunks/8815-a3d30cde6722147a.js","7317","static/chunks/7317-e53b91f569d5aae3.js","1760","static/chunks/1760-823e5ede79a02405.js","8454","static/chunks/app/journal/%5Bslug%5D/page-978ee4012cc7c4c6.js"],"default"] 22:I[60423,["2399","static/chunks/53c0104b-0bf61919c7da6d97.js","8500","static/chunks/8500-2f0b37d47b98252b.js","8815","static/chunks/8815-a3d30cde6722147a.js","7317","static/chunks/7317-e53b91f569d5aae3.js","1760","static/chunks/1760-823e5ede79a02405.js","8454","static/chunks/app/journal/%5Bslug%5D/page-978ee4012cc7c4c6.js"],"default"] 23:Tfc4,

以前の記事でも触れた通り、現在進行形で写真の整理を進めている。
Macの写真アプリからデータを抽出し、大容量のHDDに Photos/YYYY/MM という構造で格納していく地道な作業だ。
複数ある写真アプリのデータを処理するため何度も自前のスクリプトを回し、最近やっと全体の80%くらいが完了した。
サイズにして約1.5TBほどになっているが、HDDの容量はまだ余裕があるので、残りも同じように処理していこうと思っていた矢先のことだった。

全く関係のないオンラインストレージ「pCloud」から、容量が上限に達したという通知が飛んできた。

pCloudの通知といえば、Lunar New Yearなどのイベント時に半ば悪質な広告のごとく上がってくることが多い。だから今回も最初はあまり信用していなかった。
それに、自分の運用ではまだ十分な余裕があるはずだったからだ。

そもそもpCloudへ同期させていたのは、iPhoneの写真データとMac上の書類のみ。せいぜい500GB程度。
ライフタイムプランで2TBを購入済みなので、まだまだ余裕があるはずだ。それなのに、管理画面上の表示は2TBを綺麗に使い切っていた。

おかしいと思い、少し調べてみることにした。
すると、pCloudの自動同期設定にある「Photos」がなぜかActiveになっていた。
昔自分で設定したのかもしれないが、正直あまり覚えていない。とりあえずInactiveに変更した。
しかし、ストレージの状況は何も変わらない。

さらにフォルダの中身を調べてみたところ、信じられない事実が判明した。
pCloudBackup ディレクトリ配下の Photos に、なぜか今整理している「外付けHDD」のPhotosデータがまるごと同期されていたのだ。
これが原因で、ストレージを一瞬で食いつぶしてしまっていた。

本当に意味不明だ。
Macのユーザーディレクトリ配下にあるPhotosを連携する設定かと思い込んでいたのだが、どういうわけか外付けHDDのデータが吸い上げられていたのだ。
/Volumes 配下なんて明示的に同期対象にしていないのに、なぜ自動で拾われるのだろうか。

原因はよくわからないが、外付けHDDのフォルダ名が「Photos」だったせいだとアタリをつけた。
一応、外付けHDDのディレクトリ名を Photos から MyPhotos に変更し、今はpCloud上に間違ってアップロードされてしまった膨大なPhotosデータを消すという、ひたすらに無駄な作業をしている。

たまにこういう「よくわからない仕様の挙動」に直面する。
だからこそ、オンラインストレージのような便利ツールを使うときは、慎重になりすぎるくらいがちょうどいいんだよなと思う。

ふと、昔の記憶が蘇ってきた。
エンジニアとして本番環境のサーバーに入って作業していた頃は、今自分が「NFS上のディレクトリにいるのか」「ローカルのディレクトリにいるのか」をものすごく気をつけていたものだ。
NFS上のデータをうっかり消したり、マウント解除したり、シンボリックリンクを飛ばしてしまったりしたら、結構洒落にならない事態になるからだ。

今回は個人の写真データのはなしなので、致命的インシデントというほどではない。
それでも、仕様が完全にブラックボックス化されている便利なオンラインツールに対して、全幅の信頼を置ききれないよなと改めて思った。

24:Tdbc,

As I mentioned in a previous article, I am currently in the process of organizing my photos.
It's the tedious work of extracting data from the Mac Photos app and storing it in a large-capacity HDD under a Photos/YYYY/MM structure.
I've run my custom script multiple times to process the data from several Photos apps, and I'm finally about 80% done.
The size is already around 1.5TB, but since the HDD still has plenty of space, I was planning to process the rest in the same way. That's when it happened.

I received a notification from "pCloud," an online storage service that had absolutely nothing to do with this task, saying that my storage limit had been reached.

When it comes to pCloud notifications, they often pop up like semi-malicious ads during events like the Lunar New Year. So, at first, I didn't completely trust it this time either.
Besides, according to how I use it, I should still have plenty of space.

In the first place, the only things I was syncing to pCloud were iPhone photo data and documents on my Mac. At most, it was about 500GB.
I had already purchased a 2TB lifetime plan, so I should have had more than enough room. Yet, the display on the management screen showed that the 2TB was completely used up.

Thinking something was wrong, I decided to look into it a little.
It turned out that "Photos" in pCloud's automatic sync settings was somehow set to Active.
I might have set it myself a long time ago, but honestly, I don't really remember. For the time being, I changed it to Inactive.
However, the storage situation didn't change at all.

When I investigated the folder contents further, an unbelievable truth came to light.
For some reason, the Photos data from the "external HDD" I am currently organizing had been synced entirely to the Photos directory under pCloudBackup.
This was the cause that had gobbled up my storage in an instant.

It truly makes no sense.
I was under the impression that it was configured to link the Photos folder directly under the Mac user directory, but somehow the data from the external HDD had been sucked up.
I never explicitly targeted anything under /Volumes for syncing, so why would it be picked up automatically?

The cause remains a mystery, but I figured it was because the folder on the external HDD was named "Photos."
Just in case, I changed the directory name on the external HDD from Photos to MyPhotos, and now I am doing the utterly useless work of deleting the massive amount of Photos data that got mistakenly uploaded to pCloud.

Occasionally, I encounter this kind of "inexplicable spec behavior."
That's exactly why I think it's better to be overly cautious when using convenient tools like online storage.

Suddenly, a memory from my past work duties came back to me.
When I was working as an engineer logging into production servers, I used to be incredibly careful about whether I was currently "in a directory on the NFS" or "in a local directory."
Because if you accidentally deleted data on the NFS, unmounted it, or blew away a symbolic link, it would turn into a situation that was no joke.

This time, it's just a story about personal photo data, so it's not a fatal incident.
Still, it made me realize once again that I cannot place absolute trust in convenient online tools whose specifications are completely black-boxed.

8:["$","article",null,{"className":"min-h-screen bg-background pb-32 text-foreground transition-colors duration-300","children":[["$","script",null,{"type":"application/ld+json","dangerouslySetInnerHTML":{"__html":"{\"@context\":\"https://schema.org\",\"@type\":\"BlogPosting\",\"headline\":\"The Pitfalls of Black-Boxed Convenience Tools: Lessons from an Unintended pCloud Sync\",\"inLanguage\":\"en\",\"datePublished\":\"2026-03-19T15:03:41.803Z\",\"dateModified\":\"2026-03-20T00:28:09.385Z\",\"image\":[],\"author\":{\"@type\":\"Person\",\"name\":\"fson\",\"url\":\"https://fsonhub.com/career\"},\"publisher\":{\"@type\":\"Organization\",\"name\":\"fsonhub\",\"logo\":{\"@type\":\"ImageObject\",\"url\":\"https://assets.fsonhub.com/fsonicon.png\"}},\"mainEntityOfPage\":{\"@type\":\"WebPage\",\"@id\":\"https://fsonhub.com/journal/unintended-pcloud-sync-and-cloud-storage-trust\"}}"}}],["$","$L21",null,{"en":"The Pitfalls of Black-Boxed Convenience Tools: Lessons from an Unintended pCloud Sync","ja":"ブラックボックス化された便利ツールの落とし穴：pCloudの予期せぬ同期から得た教訓"}],["$","nav",null,{"className":"fixed inset-x-0 top-0 z-50 border-b border-usu bg-background/85 backdrop-blur-md dark:border-usu-dark","children":["$","div",null,{"className":"px-6","children":["$","div",null,{"className":"mx-auto flex h-14 max-w-5xl items-center justify-between","children":[["$","$L6",null,{"href":"/","aria-label":"fsonhub Home","className":"$undefined","children":["$","div",null,{"className":"flex items-baseline text-sumi dark:text-sumi-dark transition-colors duration-300","children":[["$","span",null,{"className":"font-display text-xl font-medium leading-none tracking-tight","children":"fson"}],["$","span",null,{"className":"font-body text-xl font-normal leading-none tracking-tight opacity-50","children":"/hub"}]]}]}],["$","$L6",null,{"href":"/journal","className":"u-label uppercase transition-colors hover:text-ai dark:hover:text-ai-dark","children":["← ",["$","$L7",null,{"en":"Back to Journal","ja":"ジャーナルに戻る"}]]}]]}]}]}],["$","main",null,{"className":"px-6 pt-32 sm:pt-40","children":["$","div",null,{"className":"mx-auto max-w-5xl","children":["$","div",null,{"className":"grid gap-4 md:grid-cols-12 md:gap-8","children":[["$","div",null,{"className":"flex gap-4 md:col-span-3 md:flex-col md:gap-1","children":[["$","time",null,{"lang":"en","dateTime":"2026-03-19T15:03:41.803Z","className":"u-label","children":"2026.03.19"}],["$","$L6",null,{"lang":"en","href":"/journal/category/Tech","className":"u-label uppercase transition-colors hover:text-ai dark:hover:text-ai-dark","children":"Tech"}]]}],["$","div",null,{"className":"min-w-0 md:col-span-9","children":[["$","$L22",null,{"titleJa":"ブラックボックス化された便利ツールの落とし穴：pCloudの予期せぬ同期から得た教訓","contentJa":"$23","titleEn":"The Pitfalls of Black-Boxed Convenience Tools: Lessons from an Unintended pCloud Sync","contentEn":"$24","tocJa":[],"tocEn":[]}],"$L25","$L26","$L27","$L28"]}]]}]}]}]]}]