<p><pre><code>    The problem with failures during rebuilds is overblown
</code></pre>
I thought I was the only one who believed that. I&#x27;ve said this on reddit before and ended on like -20 votes with people blatantly arguing I&#x27;m falsifying an &quot;impossibility&quot;.<p>I&#x27;ve got roughly 30 arrays in production, between 4 and 12 disks in each. All are RAID5 + hotspare. If you believe the maths people keep quoting, the odds of seeing a total failure in a given year is close to 100%. I started using this configuration, across varying hardware, over 15 years ago and I&#x27;ve been growing in number since.<p>I&#x27;m not pretending one example proves the rule, or that it&#x27;s totally safe and I would run a highly critical environment this way (before anyone comments: these environments do not meet that definition), but people have tried to show maths that there&#x27;s a six nine likelihood of failure, and I just don&#x27;t for a second believe I&#x27;m that lucky.