Re: Reusing partitions in the proposal
On Tuesday 2016-04-12 10:04, Ancor Gonzalez Sosa wrote:
Right now the mechanism to reuse existing partitions is not 100% clear.
Case 1 - EFI partition
If there is already an EFI partition in the system, the VolumesGenerator will not include an EFI partition in the list of volumes (since we don't need to create it). It's not clear to me who/when will do the actual work of reusing the existing partition.
Case 2 - Swap
Right now, VolumesGenerator always includes a swap volume, even if there is one in the system. This PBI suggests that deciding between creating a new partition or resizing an existing one would be a task for SpaceMaker and PartitionCreator.
We need a more consistent approach. Ideas?
Maybe having something like vol.reuse_device = "/dev/sdc3" so the VolumesGenerator already decides that?
Something for settings? Like reuse_efi_system_partition, reuse_swap? BTW, the ml is opensuse-storage; Cc-ing. Steffen -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
Hi, On 12.4.2016 13:48, Steffen Winterfeldt wrote:
On Tuesday 2016-04-12 10:04, Ancor Gonzalez Sosa wrote:
Right now the mechanism to reuse existing partitions is not 100% clear.
Case 1 - EFI partition
If there is already an EFI partition in the system, the VolumesGenerator will not include an EFI partition in the list of volumes (since we don't need to create it). It's not clear to me who/when will do the actual work of reusing the existing partition.
Well, I think that this depends on the full context. If there is other operating system installed and we keep it (or just resize its partition), we should also keep its EFI partition. OTOH if the system is deleted completely (e.g. because there is no way to stick the new system to the disk in addition to the existing one), its EFI should go too. Sharing the EFI partition with system we know nothing about could be dangerous - I remember Raymund telling me that - not sure which system - always wipes its EFI partition when reinstalling bootloader. Jiri
Case 2 - Swap
Right now, VolumesGenerator always includes a swap volume, even if there is one in the system. This PBI suggests that deciding between creating a new partition or resizing an existing one would be a task for SpaceMaker and PartitionCreator.
We need a more consistent approach. Ideas?
Maybe having something like vol.reuse_device = "/dev/sdc3" so the VolumesGenerator already decides that?
Something for settings? Like reuse_efi_system_partition, reuse_swap?
BTW, the ml is opensuse-storage; Cc-ing.
Steffen
-- Regards, Jiri Srain Project Manager --------------------------------------------------------------------- SUSE LINUX, s.r.o. e-mail: jsrain@suse.com Lihovarska 1060/12 tel: +420 284 084 659 190 00 Praha 9 fax: +420 284 084 001 Czech Republic http://www.suse.com -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 04/12/2016 01:48 PM, Steffen Winterfeldt wrote:
On Tuesday 2016-04-12 10:04, Ancor Gonzalez Sosa wrote:
Right now the mechanism to reuse existing partitions is not 100% clear.
Case 1 - EFI partition
If there is already an EFI partition in the system, the VolumesGenerator will not include an EFI partition in the list of volumes (since we don't need to create it). It's not clear to me who/when will do the actual work of reusing the existing partition.
Case 2 - Swap
Right now, VolumesGenerator always includes a swap volume, even if there is one in the system. This PBI suggests that deciding between creating a new partition or resizing an existing one would be a task for SpaceMaker and PartitionCreator.
We need a more consistent approach. Ideas?
Maybe having something like vol.reuse_device = "/dev/sdc3" so the VolumesGenerator already decides that?
Something for settings? Like reuse_efi_system_partition, reuse_swap?
I'm pretty sure we will have cases in which we will need to reuse the EFI partition (installing alongside Windows, for example). The case of swap is more complex. I'm not even sure it's generally a good idea to share swap. In any case, we need some mechanism to implement reusing of partitions... and to define what reusing means. See my thoughts (with a final important question) here: https://public.pad.fsfe.org/p/libstorage-ng-reusing Cheers -- Ancor González Sosa YaST Team at SUSE Linux GmbH -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 13.4.2016 14:01, Ancor Gonzalez Sosa wrote:
On 04/12/2016 01:48 PM, Steffen Winterfeldt wrote:
On Tuesday 2016-04-12 10:04, Ancor Gonzalez Sosa wrote:
Right now the mechanism to reuse existing partitions is not 100% clear.
Case 1 - EFI partition
If there is already an EFI partition in the system, the VolumesGenerator will not include an EFI partition in the list of volumes (since we don't need to create it). It's not clear to me who/when will do the actual work of reusing the existing partition.
Case 2 - Swap
Right now, VolumesGenerator always includes a swap volume, even if there is one in the system. This PBI suggests that deciding between creating a new partition or resizing an existing one would be a task for SpaceMaker and PartitionCreator.
We need a more consistent approach. Ideas?
Maybe having something like vol.reuse_device = "/dev/sdc3" so the VolumesGenerator already decides that? Something for settings? Like reuse_efi_system_partition, reuse_swap? I'm pretty sure we will have cases in which we will need to reuse the EFI partition (installing alongside Windows, for example).
What prevents us from having two EFI partitions? Jiri
The case of swap is more complex. I'm not even sure it's generally a good idea to share swap.
In any case, we need some mechanism to implement reusing of partitions... and to define what reusing means.
See my thoughts (with a final important question) here: https://public.pad.fsfe.org/p/libstorage-ng-reusing
Cheers
-- Regards, Jiri Srain Project Manager --------------------------------------------------------------------- SUSE LINUX, s.r.o. e-mail: jsrain@suse.com Lihovarska 1060/12 tel: +420 284 084 659 190 00 Praha 9 fax: +420 284 084 001 Czech Republic http://www.suse.com -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 04/13/2016 02:10 PM, Jiri Srain wrote:
On 13.4.2016 14:01, Ancor Gonzalez Sosa wrote:
On 04/12/2016 01:48 PM, Steffen Winterfeldt wrote:
On Tuesday 2016-04-12 10:04, Ancor Gonzalez Sosa wrote:
Right now the mechanism to reuse existing partitions is not 100% clear.
Case 1 - EFI partition
If there is already an EFI partition in the system, the VolumesGenerator will not include an EFI partition in the list of volumes (since we don't need to create it). It's not clear to me who/when will do the actual work of reusing the existing partition.
Case 2 - Swap
Right now, VolumesGenerator always includes a swap volume, even if there is one in the system. This PBI suggests that deciding between creating a new partition or resizing an existing one would be a task for SpaceMaker and PartitionCreator.
We need a more consistent approach. Ideas?
Maybe having something like vol.reuse_device = "/dev/sdc3" so the VolumesGenerator already decides that? Something for settings? Like reuse_efi_system_partition, reuse_swap? I'm pretty sure we will have cases in which we will need to reuse the EFI partition (installing alongside Windows, for example).
What prevents us from having two EFI partitions?
Generally speaking, maybe nothing. But still I'm sure there will be scenarios in which we need to reuse an existing one. For example, AFAIK some versions of Windows are not installable in disks with more than one EFI partition. Cheers
The case of swap is more complex. I'm not even sure it's generally a good idea to share swap.
In any case, we need some mechanism to implement reusing of partitions... and to define what reusing means.
See my thoughts (with a final important question) here: https://public.pad.fsfe.org/p/libstorage-ng-reusing
Cheers
-- Ancor González Sosa YaST Team at SUSE Linux GmbH -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 13.04.2016 14:10, Jiri Srain wrote:
What prevents us from having two EFI partitions?
The EFI standard? I had understood that there can only be one EFI system partition. Maybe I am wrong; but we should investigate this. https://en.wikipedia.org/wiki/EFI_system_partition "The globally unique identifier (GUID) for the EFI System partition in the GUID Partition Table (GPT) scheme is C12A7328-F81F-11D2-BA4B-00A0C93EC93B, while its ID in the MBR partition table scheme is 0xEF." I.e. there is a paredefined GUID for that partition; if there are multiple ones, they'd get the same GUID which sounds like a recipe for desaster to me. It doesn't even seem to be clear if another disk can have one, too: http://superuser.com/questions/688617/how-many-efi-system-partitions-esp-can... But we should clearly get some authoritative answer from our resident EFI specialists (Raymund Will (?) - couldn't reach him on the phone just now). Kind regards -- Stefan Hundhammer <shundhammer@suse.de> YaST Developer SUSE Linux GmbH GF: Felix Imendörffer, Jane Smithard, Graham Norton; HRB 21284 (AG Nürnberg) Maxfeldstr. 5, 90409 Nürnberg, Germany -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 13.04.2016 15:46, Stefan Hundhammer wrote:
https://en.wikipedia.org/wiki/EFI_system_partition
"The globally unique identifier (GUID) for the EFI System partition in the GUID Partition Table (GPT) scheme is C12A7328-F81F-11D2-BA4B-00A0C93EC93B, while its ID in the MBR partition table scheme is 0xEF."
I.e. there is a paredefined GUID for that partition; if there are multiple ones, they'd get the same GUID which sounds like a recipe for desaster to me.
OK, forget that one; Arvin just told me that this is not the ID of that partition, but the type (that was a one-byte value like 0x83 for Linux, 0x82 for swap etc.). Still that doesn't clarify if there can be multiple ones. CU -- Stefan Hundhammer <shundhammer@suse.de> YaST Developer SUSE Linux GmbH GF: Felix Imendörffer, Jane Smithard, Graham Norton; HRB 21284 (AG Nürnberg) Maxfeldstr. 5, 90409 Nürnberg, Germany -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 13.4.2016 15:53, Stefan Hundhammer wrote:
On 13.04.2016 15:46, Stefan Hundhammer wrote:
https://en.wikipedia.org/wiki/EFI_system_partition
"The globally unique identifier (GUID) for the EFI System partition in the GUID Partition Table (GPT) scheme is C12A7328-F81F-11D2-BA4B-00A0C93EC93B, while its ID in the MBR partition table scheme is 0xEF."
I.e. there is a paredefined GUID for that partition; if there are multiple ones, they'd get the same GUID which sounds like a recipe for desaster to me.
OK, forget that one; Arvin just told me that this is not the ID of that partition, but the type (that was a one-byte value like 0x83 for Linux, 0x82 for swap etc.).
Still that doesn't clarify if there can be multiple ones.
Not 100% sure I still remember everything correctly, IIRC Raymund told me (some 10+ years ago) that some operating systems wipe the contents of the partition completely when reinitializing bootloader - which effectively prevents any sharing. Stefan, thanks for reaching out to Raymund to get this clarified... Jiri -- Regards, Jiri Srain Project Manager --------------------------------------------------------------------- SUSE LINUX, s.r.o. e-mail: jsrain@suse.com Lihovarska 1060/12 tel: +420 284 084 659 190 00 Praha 9 fax: +420 284 084 001 Czech Republic http://www.suse.com -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On 13.04.2016 15:53, Stefan Hundhammer wrote:
Still that doesn't clarify if there can be multiple ones.
I just had a first talk with Raymund (will continue; he had to do something urgent in between): There can be any number of EFI system partitions. This is normally not a problem - except sometimes for Windows, so Raymund said. Which bootloader will be used when there are multiple ESPs seems to be a problem, though; basically, the admin should explicitly specify that in NVRAM (?) variables. If he doesn't do that (or doesn't even know that this option exists), according to Raymund it depends on the EFI implementation of that machine; different vendors seem to use different strategies here. http://superuser.com/questions/688617/how-many-efi-system-partitions-esp-can... https://en.wikipedia.org/wiki/EFI_system_partition Tentative outlook - this will need further discussion: It might be necessary to handle this differently depending on whether or not there is a Windows partition on the system; it might be useful to reuse the existing ESP in that case to avoid confusing Windows (or a non-expert user who doesn't know how to set those NVRAM variables). Raymund is really busy before tomorrow's deadline; he promised we will continue with this next week. Kind regards -- Stefan Hundhammer <shundhammer@suse.de> YaST Developer SUSE Linux GmbH GF: Felix Imendörffer, Jane Smithard, Graham Norton; HRB 21284 (AG Nürnberg) Maxfeldstr. 5, 90409 Nürnberg, Germany -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
On Wed, Apr 13, 2016 at 03:46:20PM +0200, Stefan Hundhammer wrote:
On 13.04.2016 14:10, Jiri Srain wrote:
What prevents us from having two EFI partitions?
The EFI standard?
I had understood that there can only be one EFI system partition. Maybe I am wrong; but we should investigate this.
https://en.wikipedia.org/wiki/EFI_system_partition
"The globally unique identifier (GUID) for the EFI System partition in the GUID Partition Table (GPT) scheme is C12A7328-F81F-11D2-BA4B-00A0C93EC93B, while its ID in the MBR partition table scheme is 0xEF."
I.e. there is a paredefined GUID for that partition; if there are multiple ones, they'd get the same GUID which sounds like a recipe for desaster to me.
On GPT each partition has a "Partition type GUID" and a "Unique partition GUID", see "GUID partition entry format" on https://en.wikipedia.org/wiki/GUID_Partition_Table. The first is just a type ID and can occur multiple times. It replaces the byte ID of MS-DOS partition tables. Surely, the EFI standard can have additional requirements on the ESP. ciao Arvin -- Arvin Schnell, <aschnell@suse.com> Senior Software Engineer, Research & Development SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) Maxfeldstraße 5 90409 Nürnberg Germany -- To unsubscribe, e-mail: opensuse-storage+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-storage+owner@opensuse.org
participants (5)
-
Ancor Gonzalez Sosa -
Arvin Schnell -
Jiri Srain -
Stefan Hundhammer -
Steffen Winterfeldt