Re: zpool labelclear destroys GPT data
On 14.06.2013, at 19:16, Tom Evans tevans...@googlemail.com wrote: I suppose if labelclear was made to check for the existence of a pre-existing ZFS label, the force flag could be used to force the change… I still don't like it, the command is not called labelclear-only-if-the-label-area-already-has-sane-data. It apparently does, because zpool labelclear would refuse to wipe a label that it believes belongs to an active zpool. So it apparently does check data. Just applies some weird logic. The logic is also flawed and annoyed me few times. For example, you want to remove a drive from an raidz. You do this by marking the drive offline and wiping it's ZFS labels, so that you can repurpose it. However, as long as the zpool is not exported, zpool labelclear refuses to wipe labels and you re forced to resort to dd. Why would it refuse to clear labels on an offlined drive? Is there better method? Daniel ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
- Original Message - From: Daniel Kalchev dan...@digsys.bg To: freebsd-stable@freebsd.org Sent: Saturday, June 15, 2013 12:39 PM Subject: Re: zpool labelclear destroys GPT data On 14.06.2013, at 19:16, Tom Evans tevans...@googlemail.com wrote: I suppose if labelclear was made to check for the existence of a pre-existing ZFS label, the force flag could be used to force the change… I still don't like it, the command is not called labelclear-only-if-the-label-area-already-has-sane-data. It apparently does, because zpool labelclear would refuse to wipe a label that it believes belongs to an active zpool. So it apparently does check data. Just applies some weird logic. The logic is also flawed and annoyed me few times. For example, you want to remove a drive from an raidz. You do this by marking the drive offline and wiping it's ZFS labels, so that you can repurpose it. However, as long as the zpool is not exported, zpool labelclear refuses to wipe labels and you re forced to resort to dd. Why would it refuse to clear labels on an offlined drive? Is there better method? I'd recommend raising a bug report and posting on the on illumos zfs list for this so its specific behavour can be discussed there, as it does sound odd to me and should in theory be quite an easy fix. Regards Steve This e.mail is private and confidential between Multiplay (UK) Ltd. and the person or entity to whom it is addressed. In the event of misdirection, the recipient is prohibited from using, copying, printing or otherwise disseminating it or any information contained in it. In the event of misdirection, illegible or incomplete transmission please telephone +44 845 868 1337 or return the E.mail to postmas...@multiplay.co.uk. ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
Kimmo Paasiala schreef: On Fri, Jun 14, 2013 at 12:22 AM, Johan Hendriks joh.hendr...@gmail.com wrote: Op 13-6-2013 14:40, Kimmo Paasiala schreef: The 'device' can be a partition as well as the whole disk, use 'zpool labelclear' on the freebsd-zfs partition instead of the whole disk. -Kimmo On Thu, Jun 13, 2013 at 3:29 PM, Johan Hendriks joh.hendr...@gmail.com wrote: When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org Thanks for your reply. I will try it on the actual zfs partition. But imho it is a bad thing that it destroys the whole disk layout. It does not remove ZFS label information, it removes ALL label information on the disk or device you give it regards Johan Hendriks Neuteboom Automatisering Of course, zpool(8) will do exactly what you tell it to do. It does not know about any partitioning schemes and assumes that the user knows that using labelclear on a the whole disk will potentially destroy all data on it including any partitioning information. -Kimmo Well as i found out, zpool(8) does not know what it clears. ! :D I think an adjustment to the man page is in order here. The man page clearly state it removes ZFS labels, not GPT, gmirror and glabel labels. It should mention it will remove labels from the disk/device, and that it clears ALL labels. If a user reads the man page it now looks save to use labelclear. I thougt that zpool would know if there was zpool label information on the disk, and if i a case there is no ZFS label information it will tell me that! In my case i did not loose anything, so no big deal but there will proberbly be someone who gets bitten by this. A plus is that i found a new way to clear my disks fast ! ;) regards Johan Hendriks ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
Le 14/06/2013 09:35, Johan Hendriks a écrit : Kimmo Paasiala schreef: On Fri, Jun 14, 2013 at 12:22 AM, Johan Hendriks joh.hendr...@gmail.com wrote: Op 13-6-2013 14:40, Kimmo Paasiala schreef: The 'device' can be a partition as well as the whole disk, use 'zpool labelclear' on the freebsd-zfs partition instead of the whole disk. -Kimmo On Thu, Jun 13, 2013 at 3:29 PM, Johan Hendriks joh.hendr...@gmail.com wrote: When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org Thanks for your reply. I will try it on the actual zfs partition. But imho it is a bad thing that it destroys the whole disk layout. It does not remove ZFS label information, it removes ALL label information on the disk or device you give it regards Johan Hendriks Neuteboom Automatisering Of course, zpool(8) will do exactly what you tell it to do. It does not know about any partitioning schemes and assumes that the user knows that using labelclear on a the whole disk will potentially destroy all data on it including any partitioning information. -Kimmo Well as i found out, zpool(8) does not know what it clears. ! :D I think an adjustment to the man page is in order here. The man page clearly state it removes ZFS labels, not GPT, gmirror and glabel labels. It should mention it will remove labels from the disk/device, and that it clears ALL labels. I agree with that, I thought too that zpool cleared only ZFS related labels. Thankfully no damage for me because it was in a script that wipe out the entire disk. regards Johan Hendriks -- Florent Peterschmitt | Please: flor...@peterschmitt.fr| * Avoid HTML/RTF in E-mail. +33 (0)6 64 33 97 92 | * Send PDF for documents. http://florent.peterschmitt.fr | Thank you :) signature.asc Description: OpenPGP digital signature
Re: zpool labelclear destroys GPT data
On 14/06/2013, at 17:05, Johan Hendriks joh.hendr...@gmail.com wrote: Of course, zpool(8) will do exactly what you tell it to do. It does not know about any partitioning schemes and assumes that the user knows that using labelclear on a the whole disk will potentially destroy all data on it including any partitioning information. Well as i found out, zpool(8) does not know what it clears. ! :D I think an adjustment to the man page is in order here. The man page clearly state it removes ZFS labels, not GPT, gmirror and glabel labels. It should mention it will remove labels from the disk/device, and that it clears ALL labels. If a user reads the man page it now looks save to use labelclear. I thougt that zpool would know if there was zpool label information on the disk, and if i a case there is no ZFS label information it will tell me that! In my case i did not loose anything, so no big deal but there will proberbly be someone who gets bitten by this. A plus is that i found a new way to clear my disks fast ! ;) It only clears ZFS labels, just because GPT gmirror information sits in a similar place doesn't make that incorrect. You are saying the equivalent of.. Why does dd if=/dev/zero of=/dev/da0 erase my whole disk, not just the first partition? ie you are giving the tool bad options and then complaining when it doesn't do what you meant :) Perhaps it should be modified to check if there is valid ZFS data there before proceeding (although that could be annoying unless there is a way to force it), and/or the man page could be amended to say it doesn't do any checks before erasing things. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au The nice thing about standards is that there are so many of them to choose from. -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On 14 June 2013 10:02, Daniel O'Connor docon...@gsoft.com.au wrote: On 14/06/2013, at 17:05, Johan Hendriks joh.hendr...@gmail.com wrote: Of course, zpool(8) will do exactly what you tell it to do. It does not know about any partitioning schemes and assumes that the user knows that using labelclear on a the whole disk will potentially destroy all data on it including any partitioning information. Well as i found out, zpool(8) does not know what it clears. ! :D I think an adjustment to the man page is in order here. The man page clearly state it removes ZFS labels, not GPT, gmirror and glabel labels. It should mention it will remove labels from the disk/device, and that it clears ALL labels. If a user reads the man page it now looks save to use labelclear. I thougt that zpool would know if there was zpool label information on the disk, and if i a case there is no ZFS label information it will tell me that! In my case i did not loose anything, so no big deal but there will proberbly be someone who gets bitten by this. A plus is that i found a new way to clear my disks fast ! ;) It only clears ZFS labels, just because GPT gmirror information sits in a similar place doesn't make that incorrect. You are saying the equivalent of.. Why does dd if=/dev/zero of=/dev/da0 erase my whole disk, not just the first partition? ie you are giving the tool bad options and then complaining when it doesn't do what you meant :) Perhaps it should be modified to check if there is valid ZFS data there before proceeding (although that could be annoying unless there is a way to force it), and/or the man page could be amended to say it doesn't do any checks before erasing things. The same goes for several geom labels. For example, if you write a geom_mirror label to a GPT-partitioned disk (as opposed to writing it to a partition within that disk), you overwrite the backup GPT table. I got recently warned not to do that (it didn't apply in my case, but still). IMHO it would be helpful to verify what's there first and warn the user about it if such an operation will overwrite a different type of label than what is about to get written there. Perhaps it should even refuse to write (by issuing an error stating that there is already a label there - and preferably also what type) until the label that's already there gets explicitly cleared by the user or until the command gets forced. Does that make sense? If you can't see the forest for the trees, Cut the trees and you'll see there is no forest. ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On 14/06/2013, at 17:48, Alban Hertroys haram...@gmail.com wrote: IMHO it would be helpful to verify what's there first and warn the user about it if such an operation will overwrite a different type of label than what is about to get written there. Perhaps it should even refuse to write (by issuing an error stating that there is already a label there - and preferably also what type) until the label that's already there gets explicitly cleared by the user or until the command gets forced. Does that make sense? The problem with this is that then each label tool needs to know about every other label format you want to detect for.. If a label format has a checksum then you could ignore a request to nuke the label if there is no valid checksum (with a flag to force). No idea how many have checksums though.. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au The nice thing about standards is that there are so many of them to choose from. -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On 14 June 2013 10:21, Daniel O'Connor docon...@gsoft.com.au wrote: On 14/06/2013, at 17:48, Alban Hertroys haram...@gmail.com wrote: IMHO it would be helpful to verify what's there first and warn the user about it if such an operation will overwrite a different type of label than what is about to get written there. Perhaps it should even refuse to write (by issuing an error stating that there is already a label there - and preferably also what type) until the label that's already there gets explicitly cleared by the user or until the command gets forced. Does that make sense? The problem with this is that then each label tool needs to know about every other label format you want to detect for.. Isn't it possible to add such information to labels, so that the tools at least know who to ask what they're dealing with? If a label format has a checksum then you could ignore a request to nuke the label if there is no valid checksum (with a flag to force). No idea how many have checksums though.. If there is no guaranteed method of identifying data on the disk as a label, then you can't warn the user in all cases. That's not particularly helpful for those cases where you can't warn the user. That's possibly a worse situation than what started this thread. -- If you can't see the forest for the trees, Cut the trees and you'll see there is no forest. ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On 14/06/2013, at 18:16, Alban Hertroys haram...@gmail.com wrote: The problem with this is that then each label tool needs to know about every other label format you want to detect for.. Isn't it possible to add such information to labels, so that the tools at least know who to ask what they're dealing with? Not really, the format of the labels is fixed, and there is no standard way they are arranged. If there is no guaranteed method of identifying data on the disk as a label, then you can't warn the user in all cases. That's not particularly helpful for those cases where you can't warn the user. That's possibly a worse situation than what started this thread. Being warned some of the time seems better than none of the time. -- Daniel O'Connor software and network engineer for Genesis Software - http://www.gsoft.com.au The nice thing about standards is that there are so many of them to choose from. -- Andrew Tanenbaum GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On Friday, June 14, 2013 4:21:08 am Daniel O'Connor wrote: On 14/06/2013, at 17:48, Alban Hertroys haram...@gmail.com wrote: IMHO it would be helpful to verify what's there first and warn the user about it if such an operation will overwrite a different type of label than what is about to get written there. Perhaps it should even refuse to write (by issuing an error stating that there is already a label there - and preferably also what type) until the label that's already there gets explicitly cleared by the user or until the command gets forced. Does that make sense? The problem with this is that then each label tool needs to know about every other label format you want to detect for.. If a label format has a checksum then you could ignore a request to nuke the label if there is no valid checksum (with a flag to force). No idea how many have checksums though.. Well, you could have zpool check if there is a valid ZFS label and prompt/warn if it doesn't find one on whatever device it's about to wipe. That doesn't fix the gmirror/gpt case, but it might make zpool more intuitive to use. -- John Baldwin ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On Fri, Jun 14, 2013 at 4:49 PM, John Baldwin j...@freebsd.org wrote: Well, you could have zpool check if there is a valid ZFS label and prompt/warn if it doesn't find one on whatever device it's about to wipe. That doesn't fix the gmirror/gpt case, but it might make zpool more intuitive to use. One of the uses of zpool labelclear is to completely wipe the portions of the disk that ZFS will look at for label information. There is no pre-condition, the post-condition is that the label areas of the supplied device will be cleared. The aim of the command is that the relevant parts of the device are cleared, regardless of its content, such that they are ready to use as pristine disks in a vdev. I suppose if labelclear was made to check for the existence of a pre-existing ZFS label, the force flag could be used to force the change… I still don't like it, the command is not called labelclear-only-if-the-label-area-already-has-sane-data. Cheers Tom ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
zpool labelclear destroys GPT data
When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
The 'device' can be a partition as well as the whole disk, use 'zpool labelclear' on the freebsd-zfs partition instead of the whole disk. -Kimmo On Thu, Jun 13, 2013 at 3:29 PM, Johan Hendriks joh.hendr...@gmail.com wrote: When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
Op 13-6-2013 14:40, Kimmo Paasiala schreef: The 'device' can be a partition as well as the whole disk, use 'zpool labelclear' on the freebsd-zfs partition instead of the whole disk. -Kimmo On Thu, Jun 13, 2013 at 3:29 PM, Johan Hendriks joh.hendr...@gmail.com wrote: When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org Thanks for your reply. I will try it on the actual zfs partition. But imho it is a bad thing that it destroys the whole disk layout. It does not remove ZFS label information, it removes ALL label information on the disk or device you give it regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
Re: zpool labelclear destroys GPT data
On Fri, Jun 14, 2013 at 12:22 AM, Johan Hendriks joh.hendr...@gmail.com wrote: Op 13-6-2013 14:40, Kimmo Paasiala schreef: The 'device' can be a partition as well as the whole disk, use 'zpool labelclear' on the freebsd-zfs partition instead of the whole disk. -Kimmo On Thu, Jun 13, 2013 at 3:29 PM, Johan Hendriks joh.hendr...@gmail.com wrote: When i use zpool labelclear, it wipes the whole disk including gpt data. So the whole disk is empty and i need to create the gpt partitions again. Is this supposed to work like this? The man page suggests that it only wipes the ZFS metadata. zpool labelclear [-f] device Removes ZFS label information from the specified device. The device must not be part of an active pool configuration. -v Treat exported or foreign devices as inactive. This is on FreeBSD 9.1 stable r251213 memstick install. regards Johan Hendriks Neuteboom Automatisering ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org Thanks for your reply. I will try it on the actual zfs partition. But imho it is a bad thing that it destroys the whole disk layout. It does not remove ZFS label information, it removes ALL label information on the disk or device you give it regards Johan Hendriks Neuteboom Automatisering Of course, zpool(8) will do exactly what you tell it to do. It does not know about any partitioning schemes and assumes that the user knows that using labelclear on a the whole disk will potentially destroy all data on it including any partitioning information. -Kimmo ___ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to freebsd-stable-unsubscr...@freebsd.org
