On 05/08/2013 04:17 PM, Tregaron Bayly wrote: > We have lots of mirrors all over our network and over time this means > arrays created by different versions of mdadm. In turn this means that > we have all sorts of data offsets, including a 2.3.5 mdadm version that > offset the data 262,144 sectors. I can't fathom why I need my data to > start 128M from the beginning of the disk, but whatever. > > Inevitably an admin decided that doing a --create over the top of an > existing array was a good and necessary thing and when finished we > couldn't find the filesystem. Bringing it back online was simply a case > of finding the correct offset, locating an mdadm version that would > specify it properly and doing another create. Through the whole > exercise I found myself wondering why there isn't a command line > argument to specify the data offset if something other than the default > is desired. I think that implementing the argument and reading the > value in init_super wouldn't be terribly difficult so I must be missing > an obvious reason. Can someone explain to me why this feature isn't > desirable? This desirable and has been implemented. Check out the development version of mdadm and look at the "--data-offset" option. It does not exist in a released version yet, but it has been cooking since October. 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
