Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
On Tue, Jan 06, 2009 at 04:10:10PM -0500, JZ wrote: > Hello Darren, > This one, ok, was a validate thought/question -- Darn, I was hoping... > On Solaris, root pools cannot have EFI labels (the boot firmware doesn't > support booting from them). > http://blog.yucas.info/2008/11/26/zfs-boot-solaris/ Yup. If that were to change, it would make this much simpler. -- Darren ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Hi Cindy, I now suspect that the boot blocks are located outside of the space in partition 0 that actually belongs to the zpool, in which case it is not necessarily a bug that zpool attach does not write those blocks, IMO. Indeed, that must be the case, since GRUB needs to get to stage2 in order to be able to read zfs file systems. I'm just glad zpool attach warned me that I need to invoke grubinstall manually! Thank you for making things less mysterious. Alex -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
On Tue, Jan 06, 2009 at 01:24:17PM -0800, Alex Viskovatoff wrote: > a...@diotiima:~# installgrub -m /boot/grub/stage1 /boot/grub/stage2 > /dev/rdsk/c4t0d0s0 > Updating master boot sector destroys existing boot managers (if any). > continue (y/n)?y > stage1 written to partition 0 sector 0 (abs 16065) > stage2 written to partition 0, 267 sectors starting at 50 (abs 16115) > stage1 written to master boot sector > a...@diotima:~# > So installgrub writes to partition 0. How does one know that those > sectors have not already been used by zfs, in its mirroring of the > first drive by this second drive? Because this is a VTOC label partition (necessary for Solaris boot), I believe ZFS lives only within slice 0 (I need to verify this). So VTOC cylinder 0 is free. > And why is writing to partition 0 even necessary? Since c3t0d0 must > contain stage1 and stage2 in its partition 0, wouldn't c4t0d0 already > have stage1 and stage 2 in its partition 0 through the silvering > process? I doubt that all of partition 0 is mirrored. Only the data under ZFS control (not the boot blocks) are copied. Do not confuse the MBR partition 0 (the "Solaris partition") with the VTOC slice 0 (the one that has all the disk cylinders other than cylinder 0 in it and that appeared in your earlier "label" output). > I don't find the present disk format/label/partitioning experience > particularly unpleasant (except for grubinstall writing directly into > a partition which belongs to a zpool). I just wish I understood what > it involves. Partition 0 contains all of Solaris. So the OS just needs to keep things straight. It does this with the VTOC slicing within that partition. > Thank you for that link to the System Administration Guide. I just > looked at it again, and it says partition 8 "Contains GRUB boot > information". So partition 8 is the master boot sector and contains > GRUB stage1? It should probably refer to "slice 8" to reduce confusion. Boot loaders (GRUB since that's what is in use here) are simultaneously in partition 0 and slice 8. -- Darren ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Thanks for clearing that up. That all makes sense. I was wondering why ZFS doesn't use the whole disk in the standard OpenSolaris install. That explains it. -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Hi Alex, The fact that you have to install the boot blocks manually on the second disk that you added with zpool attach is a bug! I should have mentioned this bug previously. If you had used the initial installation method to create a mirrored root pool, the boot blocks would have been applied automatically. I don't think a way exists to discern whether the boot blocks are already applied. I can't comment on why resilvering can't do this step. Cindy Alex Viskovatoff wrote: > Cindy, > > Well, it worked. The system can boot off c4t0d0s0 now. > > But I am still a bit perplexed. Here is how the invocation of installgrub > went: > > a...@diotiima:~# installgrub -m /boot/grub/stage1 /boot/grub/stage2 > /dev/rdsk/c4t0d0s0 > Updating master boot sector destroys existing boot managers (if any). > continue (y/n)?y > stage1 written to partition 0 sector 0 (abs 16065) > stage2 written to partition 0, 267 sectors starting at 50 (abs 16115) > stage1 written to master boot sector > a...@diotima:~# > > So installgrub writes to partition 0. How does one know that those sectors > have not already been used by zfs, in its mirroring of the first drive by > this second drive? And why is writing to partition 0 even necessary? Since > c3t0d0 must contain stage1 and stage2 in its partition 0, wouldn't c4t0d0 > already have stage1 and stage 2 in its partition 0 through the silvering > process? > > I don't find the present disk format/label/partitioning experience > particularly unpleasant (except for grubinstall writing directly into a > partition which belongs to a zpool). I just wish I understood what it > involves. > > Thank you for that link to the System Administration Guide. I just looked at > it again, and it says partition 8 "Contains GRUB boot information". So > partition 8 is the master boot sector and contains GRUB stage1? > > Alex ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Cindy, Well, it worked. The system can boot off c4t0d0s0 now. But I am still a bit perplexed. Here is how the invocation of installgrub went: a...@diotiima:~# installgrub -m /boot/grub/stage1 /boot/grub/stage2 /dev/rdsk/c4t0d0s0 Updating master boot sector destroys existing boot managers (if any). continue (y/n)?y stage1 written to partition 0 sector 0 (abs 16065) stage2 written to partition 0, 267 sectors starting at 50 (abs 16115) stage1 written to master boot sector a...@diotima:~# So installgrub writes to partition 0. How does one know that those sectors have not already been used by zfs, in its mirroring of the first drive by this second drive? And why is writing to partition 0 even necessary? Since c3t0d0 must contain stage1 and stage2 in its partition 0, wouldn't c4t0d0 already have stage1 and stage 2 in its partition 0 through the silvering process? I don't find the present disk format/label/partitioning experience particularly unpleasant (except for grubinstall writing directly into a partition which belongs to a zpool). I just wish I understood what it involves. Thank you for that link to the System Administration Guide. I just looked at it again, and it says partition 8 "Contains GRUB boot information". So partition 8 is the master boot sector and contains GRUB stage1? Alex -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Hello Darren, This one, ok, was a validate thought/question -- On Solaris, root pools cannot have EFI labels (the boot firmware doesn't support booting from them). http://blog.yucas.info/2008/11/26/zfs-boot-solaris/ But again, this is a ZFS discussion, and obvously EFI is not a ZFS, or even Sun thing. http://en.wikipedia.org/wiki/Extensible_Firmware_Interface Hence, on ZFS turf, I would offer the following comment, in the notion of innovation, not trashing EFI. The ZFS design point is to "make IT simple", so EFI or not EFI can be debate-able. http://kerneltrap.org/node/6884 ;-) best, z - Original Message - From: "A Darren Dunham" To: Sent: Tuesday, January 06, 2009 3:38 PM Subject: Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme > On Tue, Jan 06, 2009 at 11:49:27AM -0700, cindy.swearin...@sun.com wrote: >> My wish for this year is to boot from EFI-labeled disks so examining >> disk labels is mostly unnecessary because ZFS pool components could be >> constructed as whole disks, and the unpleasant disk >> format/label/partitioning experience is just a dim memory... > > Is there any non-EFI hardware that would support EFI boot? > > -- > Darren > ___ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
On Tue, Jan 06, 2009 at 11:49:27AM -0700, cindy.swearin...@sun.com wrote: > My wish for this year is to boot from EFI-labeled disks so examining > disk labels is mostly unnecessary because ZFS pool components could be > constructed as whole disks, and the unpleasant disk > format/label/partitioning experience is just a dim memory... Is there any non-EFI hardware that would support EFI boot? -- Darren ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
> http://docs.sun.com/app/docs/doc/817-5093/disksconcepts-20068?a=view > > (To add more confusion, partitions are also referred to as slices.) Nope, at least not on x86 systems. A partition holds the Solaris part of the disk, and that part is subdivided into slices. Partitions are visible to other OSes on the box; slices aren't. Whereever the wrong term appears in Sun docs, it should be treated as a doc bug. For Sparc systems, some people intermix the two terms, but it's not really correct there either. Regards -- Volker -- Volker A. Brandt Consulting and Support for Sun Solaris Brandt & Brandt Computer GmbH WWW: http://www.bb-c.de/ Am Wiesenpfad 6, 53340 Meckenheim Email: v...@bb-c.de Handelsregister: Amtsgericht Bonn, HRB 10513 Schuhgröße: 45 Geschäftsführer: Rainer J. H. Brandt und Volker A. Brandt ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
On Tue, Jan 06, 2009 at 10:22:20AM -0800, Alex Viskovatoff wrote: > I did an install of OpenSolaris in which I specified that the whole disk > should be used for the installation. Here is what "format> verify" produces > for that disk: > > Part TagFlag Cylinders SizeBlocks > 0 rootwm 1 - 60797 465.73GB(60797/0/0) 976703805 > 1 unassignedwm 00 (0/0/0) 0 > 2 backupwu 0 - 60797 465.74GB(60798/0/0) 976719870 > 3 unassignedwm 00 (0/0/0) 0 > 4 unassignedwm 00 (0/0/0) 0 > 5 unassignedwm 00 (0/0/0) 0 > 6 unassignedwm 00 (0/0/0) 0 > 7 unassignedwm 00 (0/0/0) 0 > 8 bootwu 0 - 07.84MB(1/0/0) 16065 > 9 unassignedwm 00 (0/0/0) 0 > > I have several questions. First, what is the purpose of partitions 2 and 8 > here? Why not simply have partition 0, the "root" partition, be the only > partition, and start at cylinder 0 as opposed to 1? It's traditional in the VTOC label to have slice 2 encompass all cylinders. You don't have to use it. In SPARC, the boot blocks fit into the 15 "free" blocks before the filesystem actually starts writing data. On x86, the boot code requires more data. So putting a UFS filesystem on cylinder 0 would not leave sufficient room for boot code. The traditional solution is that data slices on x86 begin at cylinder 1, leaving cylinder 0 for boot data. -- Darren ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] Questions about OS 2008.11 partitioning scheme
Alex, I think the root cause of your confusion is that the format utility and disk labels are very unfriendly and confusing. Partition 2 identifies the whole disk and on x86 systems, space is needed for boot-related information and is currently stored in partition 8. Neither of these partitions require any administration and should not be used for anything. You can read more here: http://docs.sun.com/app/docs/doc/817-5093/disksconcepts-20068?a=view (To add more confusion, partitions are also referred to as slices.) However, the system actually boots from the root file system, in partition 0 on your system, which is why you need to run the installgrub command on c4t0d0s0. Your installgrub syntax looks correct to me. My wish for this year is to boot from EFI-labeled disks so examining disk labels is mostly unnecessary because ZFS pool components could be constructed as whole disks, and the unpleasant disk format/label/partitioning experience is just a dim memory... Cindy Alex Viskovatoff wrote: > Hi all, > > I did an install of OpenSolaris in which I specified that the whole disk > should be used for the installation. Here is what "format> verify" produces > for that disk: > > Part TagFlag Cylinders SizeBlocks > 0 rootwm 1 - 60797 465.73GB(60797/0/0) 976703805 > 1 unassignedwm 00 (0/0/0) 0 > 2 backupwu 0 - 60797 465.74GB(60798/0/0) 976719870 > 3 unassignedwm 00 (0/0/0) 0 > 4 unassignedwm 00 (0/0/0) 0 > 5 unassignedwm 00 (0/0/0) 0 > 6 unassignedwm 00 (0/0/0) 0 > 7 unassignedwm 00 (0/0/0) 0 > 8 bootwu 0 - 07.84MB(1/0/0) 16065 > 9 unassignedwm 00 (0/0/0) 0 > > I have several questions. First, what is the purpose of partitions 2 and 8 > here? Why not simply have partition 0, the "root" partition, be the only > partition, and start at cylinder 0 as opposed to 1? > > My second question concerns the disk I have used to mirror the first root > zpool disk. After I set up the second disk to mirror the first one with > "zpool attach -f rpool c3t0d0s0 c4t0d0s0", I got the response > > Please be sure to invoke installgrub(1M) to make 'c4t0d0s0' bootable. > > Is that correct? Or do I want to make c4t0d0s8 bootable, given that the label > of that partition is "boot"? I cannot help finding this a little confusing. > As far as i can tell, c4t0d0s8 (as well as c3t0d0s8 from the original disk > which I mirrored), cylinder 0, is not used for anything. > > Finally, is the correct command to make the disk I have added to mirror the > first disk bootable > > "installgrub -m /boot/grub/stage1 /boot/grub/stage2 /dev/rdsk/c4t0d0s0" ? ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] Questions about OS 2008.11 partitioning scheme
Hi all, I did an install of OpenSolaris in which I specified that the whole disk should be used for the installation. Here is what "format> verify" produces for that disk: Part TagFlag Cylinders SizeBlocks 0 rootwm 1 - 60797 465.73GB(60797/0/0) 976703805 1 unassignedwm 00 (0/0/0) 0 2 backupwu 0 - 60797 465.74GB(60798/0/0) 976719870 3 unassignedwm 00 (0/0/0) 0 4 unassignedwm 00 (0/0/0) 0 5 unassignedwm 00 (0/0/0) 0 6 unassignedwm 00 (0/0/0) 0 7 unassignedwm 00 (0/0/0) 0 8 bootwu 0 - 07.84MB(1/0/0) 16065 9 unassignedwm 00 (0/0/0) 0 I have several questions. First, what is the purpose of partitions 2 and 8 here? Why not simply have partition 0, the "root" partition, be the only partition, and start at cylinder 0 as opposed to 1? My second question concerns the disk I have used to mirror the first root zpool disk. After I set up the second disk to mirror the first one with "zpool attach -f rpool c3t0d0s0 c4t0d0s0", I got the response Please be sure to invoke installgrub(1M) to make 'c4t0d0s0' bootable. Is that correct? Or do I want to make c4t0d0s8 bootable, given that the label of that partition is "boot"? I cannot help finding this a little confusing. As far as i can tell, c4t0d0s8 (as well as c3t0d0s8 from the original disk which I mirrored), cylinder 0, is not used for anything. Finally, is the correct command to make the disk I have added to mirror the first disk bootable "installgrub -m /boot/grub/stage1 /boot/grub/stage2 /dev/rdsk/c4t0d0s0" ? -- This message posted from opensolaris.org ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
