killercheung

回覆 19# harryytm

除非你隻 harddisk 12T, 正常Rebuild 比盡你都係一日，除非你部機比雷劈 ／ 火牛爆炸，唔係都好少可兩隻咁近時間壞啦  

就算你set 左部機定時自動 backup，總會有機會因為某 d 問題 backup 失敗，通常 harddisk 就係呢 d 時間壞架啦，呢個機會一定高過你兩隻 raid 1 harddisk 一齊壞！

RAID 係用來對付硬件突然出現問題 ，BACKUP 就係用來對付人為錯誤 ／ 中毒 ／ 大災難，兩者都缺一不可喎

-13-

回覆 21# killercheung


理論上係好難發生咁橋既事

但現實上好似唔少聽到

harryytm

回覆  killercheung


理論上係好難發生咁橋既事

但現實上好似唔少聽到 ...
-13- 發表於 2017-5-11 02:19

我就見唔少Rebuild RAID 1/5/6中途壞多隻而全部檔案Total lost嘅事發生

起得RAID啲碟通常係一次過買返去起，而且係同一型號同一批次，序號仲要係好接近嘅，即係你個RAID用幾耐，成組RAID嘅硬碟就要開足咁耐，就連讀寫數量都係一樣，全部碟嘅損耗一樣，硬件突然壞嘅風險，行RAID同只行一部HDD等同啦！

Free888

多謝各位師兄，會參考再諗諗。本身都有部external HDD可以做backup。SSD應該會買大D但係唔需要極快，例如Crucial MX300 525Gb。HDD其實2TG都夠，未決定買邊隻。。

killercheung

回覆 23# harryytm

照你地咁講點解全世界 server 都會行 raid ，行單隻慢慢 backup就得啦

-13-

回覆 26# killercheung


RAID就梗要行

但係容錯要做大啲

pc1668

我就見唔少Rebuild RAID 1/5/6中途壞多隻而全部檔案Total lost嘅事發生

起得RAID啲碟通常係一次過買返去起，而且係同一型號同一批次，序號仲要係好接近嘅，即係你個RAID用幾耐，成組RAID嘅硬碟就要開足咁耐，就連讀寫數量都係一樣，全部碟嘅損耗一樣，硬件突然壞嘅風險，行RAID同只行一部HDD等同啦！
harryytm 發表於 2017-5-11 02:31

Yes, it happens from time to time.  I would treat the rebuild process as a 'nice to have' feature.  And never expect it to be a kind of 'must work' recovery process.

twaiho2003

回覆 26# killercheung


    因為行raid 係為左HA,
而佢講果個情況, 我諗係保養期內發生機會不大 (掛),
淨返既HDD廠得4間, 爛船都有3分釘,
如果廠愈左用4年, 唔會寫5年保落去

另外, 出自data center果D HDD failure rate report ,  都有4個牌子既HDD,
姐係data center 都會買4個牌子既hdd,

pc1668

回復 pc1668

need extra cost  

via HKEPC Reader for Android
takayo72 發表於 2017-5-11 10:03

Tell you a short story.

My friend has a notebook with 1TB hdd (I think) holding thousands of pics captured in the past 5 to 10 years.  One day the HDD died, and there was no backup copy (never have one).  All pics were gone with the wind as expected.  

After encountering such catastrophic disaster, my friend has bought two 2TB portable HDDs, one for production and the other for backup.  One backup copy is the minimal requirement.  And it's very easy to setup.  Actually I have three backup copies for important files.

With whatever storage approach we adopt (NAS, internal hdd, portable hdd, etc.), backup is very important.  Even if we're going to use public cloud storage service, I think we still need to prepare some kind of offline backup plan.