----- Original Message ----- From: "Neil Brown" <neilb@xxxxxxxxxxxxxxx> To: <djani22@xxxxxxxxxxxxx> Cc: <linux-raid@xxxxxxxxxxxxxxx> Sent: Thursday, August 18, 2005 6:34 AM Subject: Re: Found a new bug! > On Monday August 15, djani22@xxxxxxxxxxxxx wrote: > > Thanks, I will test it, when I can... > > > > In this moment, my system is an working online system, and now only one 8TB > > space what I can use... > > Thats right, maybe I can built linear array from only one soure device,but: > > My first problem is, on my 8TB device is already exists XFS filesystem, with > > valuable data, what I can't backup. > > It is still OK, but I can't insert one raid layer, because the raid's > > superblock, and the XFS is'nt shrinkable. :-( > > > > The only one way (I think) to plug in another raw device, and build an array > > from 8TB-device + new small device, to get much space to FS. > > > > But it is too risky for me! > > Yes, I wouldn't bother just for testing. I've managed to put together > some huge devices with spare files and multi-layer linear arrays (ext3 > won't allow files as big as 2TB) and I am happy that the patch works. > > Longer term, I have been thinking of enhancing mdadm so that when you > create a linear array, it copies the few blocks from the end that will > be over written by the superblock onto the start of the second > device. This would allow a single device to be extended into a linear > array without loss. (I also have patches to hot-add devices to the > end of a linear array which I really should dust-off and get into > mainline). Yes! This is very good idea! I can do that manually with dd, but some people can't. This, and sometimes reverse of this is a usefull options! In my case: I add some small HDD to my big array, to try the patch. Thats ok. But later, when I try to change the small to another big, there is no easy way, to do this. When I copy the small drive with dd or cat to 2nd big array, the superblock is wrong placed. (or not?) > > > > Do you think it is safe? > > > > Currently I use 2.6.13-rc3. > > This patch is good for this version, or only the last version? > > > > Witch is the last? 2.6.13-rc6 or rc6-git7, or 2.6.14 -git cvs? :) > > The patch should be good against any reasonable recent version of > 2.6. I always work against the latest -mm, but this code has been > largely untouched for a while so there shouldn't be any patch > conflicts. Thanks, I will try it! But in the last month my system's downtime is almost more than uptime, and now I try to fix this very bad stat. :-) Janos - 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
