On Thu, Dec 07, 2017 at 09:52:55AM +0000, Richard Bradfield wrote: > On Thu, 7 Dec 2017, at 09:28, Frank Steinmetzger wrote: > > > I incorporated ZFS' expansion inflexibility into my planned > > > maintenance/servicing budget. > > > > What was the conclusion? That having no more free slots meant that you > > can just as well use the inflexible Raidz, otherwise would have gone with > > Mirror? > > Correct, I had gone back and forth between RaidZ2 and a pair of Mirrors. > I needed the space to be extendable, but I calculated my usage growth > to be below the rate at which drive prices were falling, so I could > budget to replace the current set of drives in 3 years, and that > would buy me a set of bigger ones when the time came.
I see. I'm always looking for ways to optimise expenses and cut down on environmental footprint by keeping stuff around until it really breaks. In order to increase capacity, I would have to replace all four drives, whereas with a mirror, two would be enough. > I did also investigate USB3 external enclosures, they're pretty > fast these days. When I configured my kernel the other day, I discovered network block devices as an option. My PC has a hotswap bay[0]. Problem solved. :) Then I can do zpool replace with the drive-to-be-replaced still in the pool, which improves resilver read distribution and thus lessens the probability of a failure cascade. [0] http://www.sharkoon.com/?q=de/node/2171
