Hi Dragon, On 06/18/2011 04:39 PM, Dragon wrote: > Monitor your background reshape with "cat /proc/mdstat". > > When the reshape is complete, the extra disk will be marked "spare". > > Then you can use "mdadm --remove". > -->after a view days the reshape was done and i take the disk out of the raid -> many thx for that Good to hear. >> at this point i think i take the disk out of the raid, because i need the space of > the disk. > > Understood, but you are living on the edge. You have no backup, and only one drive > of redundancy. If one of your drives does fail, the odds of losing the whole array > while replacing it is significant. Your Samsung drives claim a non-recoverable read > error rate of 1 per 1x10^15 bits. Your eleven data disks contain 1.32x10^14 bits, > all of which must be read during rebuild. That means a _13%_ chance of total > failure while replacing a failed drive. > > I hope your 16T of data is not terribly important to you, or is otherwise replaceable. > --> nice calculation, where do you have the data from? > --> most of it is important, i will look for a better solution The error rate is from Samsung, for your HD154UI drives: http://www.samsung.com/latin_en/consumer/monitor-peripherals-printer/hard-disk-drives/internal/HD154UI/CKW/index.idx?pagetype=prd_detail&tab=specification error rate = 1 / 1*10^15 = 1x10^-15 The rest comes from your setup: 11 disks * (1465138496 * 1024) bytes/disk * 8 bits/bytes = 1.32026560152e+14 % odds of failure = (data quantity * error rate) * 100% [...] > --> and than, ext4 max size is actually 16TB, what should i do? I've been playing with XFS. The only significant maintenance drawback I've identified is that it cannot be shrunk. Not even offline. It's not really holding me back, though, as I tend to layer LVM on top of my raid arrays, then allocate to specific volumes. I always hold back a substantial fraction of the space for future use of "lvextend". > --> for an end-user you have many knowledge about swraid ;) Thank you. I was a geek before I became an engineer :) . Phil -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
