# Week 0x04 - 第一次自由分享 (2025/04/26)
> [color=#8805bc][time=Sat Apr 26 2025 21:30:00]

[TOC]

## DF 大大的分享

- 主題：「備份」淺論生活中的數位資料保存
- 簡報：{%preview https://hackmd.io/@dfder/S1MGe_DJxl %}
- 共筆：
- 主要分享資料的安全
- 新聞時有耳聞誤刪資料
- GitLab 資料不見好可怕
- 生活跟資料息息相關，所以常常會出現備份的問題
- 什麼是備份？
- 檔案有一個或以上的副本
- 有第二個計劃可以不中斷系統運作
- 備份的可靠性?
- 分類方法
- 名稱
- 時間
- 服務 (service)
- 沒有最好的分類方法
- 不同資料會適合不同的備份方案
- 進階參考：圖書資訊管理、資訊檢索
- 存取頻率
- 冷資料：比較少存取
- 熱資料：經常存取
- **3-2-1 備份法**
- 3 份資料
- example: 我的電腦有一份、我的隨身碟也有一份、別人的硬碟也有一份
- 2 種媒介
- 資料的存放平台
- 媒介 (media)：儲存資料的方式
- e.g., usb、硬碟、光碟、甚至刻在牆壁上
- 1 個異地備份
- 遠端, 本地 / 實體
- 儲存媒介 pros & cons
- nand flash
- flash = 記憶體顆粒；nand = 一種邏輯閘
- 人話：你 ssd 上面的東西
- 
- 缺點是有寫入次數上限，有一天會突然掛掉
- 太久沒插電腦充電，可能會忘記資料
- 一般 USB 1k~3k read/write
- 企業級產品壽命讀寫 30k 次起跳0
- 光碟
- 成本非常低
- 用微小凹槽存資料
- 沒有物理損傷的話可以長期存放
- 建議存冷資料
- 刮傷就 GG 了
- 延伸閱讀: {%preview https://www.ithome.com.tw/tech/160482 %}
- hdd 硬碟
- 跟光碟很像，不過是使用磁力梯度
- 低成本
- 很怕磁鐵, 碰撞
- 裡面是高速旋轉的碟盤，碰下去你的資料跟碟盤碎片可能會延切線方向飛出
- LTO磁帶
- 用磁力梯度儲存
- 儲存密度很高，並且很耐久，適合大規模使用
- 但也幾乎是唯一優點了
- 只能循序讀取
- 原則上只會存放冷資料
- 一般人該怎麼做？
- ~~買個幾家雲端儲存服務，人家會幫你做好~~
- “異地“ 可以透過放在雲端硬碟來解決
- 要衡量要放什麼資料，可能不是什麼東西都要放在雲端上
- 進階的做法
- NAS (network attached storage)
- 基於網路的儲存裝置
- 消費級 NAS 特徵：簡單易用、附加軟體
- 硬碟陣列 (RAID, redundant array of independent disks)
- 用多顆硬碟來提高可靠度
- ~~JBOD~~
- RAID 0 -> 壞一顆就會掉資料
- RAID 1 -> 同個資料寫進不同硬碟
- RAID 有多種結構策略(?): 1,3,5...
- **冗餘不等於備份**
- 消費級 NAS 就是有冗餘設計的電腦
- Data Gateway
- 資料集散地
- 對使用者來說越簡單越好
- 往 TrueNAS 丟，資料先進 Array，再備份到 Remote

## Penut Share
- 簡報：{%preview https://hackmd.io/@hell-kitty/PublishExp %}
- 共筆：
- 鐵人賽隊員招募中
- 為什麼參賽？
- 窩不知道
- 常常 google 到鐵人賽文章覺得可以試試
- 賽前準備
- 先選定主題
- 可以先寫好 (存稿)，鐵人賽時一天丟一篇出來
- 也可以直接上 (裸賽) ==賊刺激==
- 比賽期間
- 跟雙十連假撞期
- 寫到後面開始亂寫 (?)
- 然後就得獎了 (?)
- ~~公審~~
- 獲得獎盃
- 1 萬
- 可以出版 (!!)
- 400頁 (~270頁 word 檔)
- 出版社只用 pdf → 用 word 寫
- 看了一下，我的只有一個"天"www
- 恭喜這位初版支持者
- AI 都在你各位的生活中阿
- 封面居然是 stable diffusion 生的 :exploding_head:
- 貓貓的手放在金手指上也太好笑xd
- 推薦序
- 動用所有人脈 (?)
- 最後找了評審、指導教授和 JT 大大
- 宣傳
- 潛伏在臉書社團
- 分享文章，得到「經常發言的成員」徽章
- 果然梗圖才是最好的宣傳媒介
- 宣傳記得要在月初 (銷量只算當月阿)

## Macha Share
- 簡報：{%preview https://docs.google.com/presentation/d/1EAODYRbHpuz5nd2_48qh9mXJy83-mk1F %}
- (延到下次)

## 聊天室

幹我忘了上來作筆記

> "我的經驗比你各位多億點點"
> [name=d.f.]
> 

真希望有人 excel pay 給我 1500 bitcoin

> 居然嗎，看來是我孤陋寡聞了
> 其實一直都可以w，see https://hackmd.io/s/features#UML-Diagrams
> ↓ 現在還可以製圖喔，真鬼

df 的音量 be like：

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df: 可靠的雲端平臺
gcp: https://www.ai-cio.com/news/google-cloud-accidentally-deletes-australian-superannuation-funds-data/

bv