* [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! [not found] <1591887.1161167319269.OPEN-XCHANGE.WebMail.wwwrun@eu.main.anykey> @ 2006-10-18 12:42 ` Andreas Octav 2006-10-18 15:33 ` Jonathan E Brassow 0 siblings, 1 reply; 6+ messages in thread From: Andreas Octav @ 2006-10-18 12:42 UTC (permalink / raw) To: linux-lvm Hi again, It seems that my Volume Groups are missing the "System ID" entry. Is this a known bug in my version? (lvm2-2.01.14-3.6) So all nodes have full access to the VG. Does not seem correct to me ... Best regards, Andreas Octav Am Mi 18.10.2006 12:28 schrieb Andreas Octav <Andreas.Octav@anykey.de>: > Hi, > > i´m new to LVM2 and wondering if it´s possible to restrict access to a > Volume Group to a single server (e.g. like under vxvm (vxdg > import/deport)). > If I import a VG by using vgimport it is still possible to access the > VG > on another node in a shared SAN environment. Can I prevent this > somehow? > > I´m using lvm2-2.01.14-3.6 on servers running SuSE SLES9 SP3 x86_64. > > Kind regards, > Andreas Octav > Consultant > > anykey GmbH > Koenigswinterer Strasse 418 > D-53227 Bonn > http://www.anykey.de > Andreas Octav Consultant anykey GmbH Koenigswinterer Strasse 418 D-53227 Bonn http://www.anykey.de ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! 2006-10-18 12:42 ` [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! Andreas Octav @ 2006-10-18 15:33 ` Jonathan E Brassow 2006-10-18 16:02 ` Andreas Octav 0 siblings, 1 reply; 6+ messages in thread From: Jonathan E Brassow @ 2006-10-18 15:33 UTC (permalink / raw) To: LVM general discussion and development >> Hi, >> >> i�m new to LVM2 and wondering if it�s possible to restrict access to a >> Volume Group to a single server (e.g. like under vxvm (vxdg >> import/deport)). >> If I import a VG by using vgimport it is still possible to access the >> VG >> on another node in a shared SAN environment. Can I prevent this >> somehow? >> >> I�m using lvm2-2.01.14-3.6 on servers running SuSE SLES9 SP3 x86_64. >> You can use tags to achieve this, or you can specify specific volume groups and logical volumes in lvm.conf under "volume_list". brassow ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! 2006-10-18 15:33 ` Jonathan E Brassow @ 2006-10-18 16:02 ` Andreas Octav 2006-10-18 16:40 ` Jonathan E Brassow 0 siblings, 1 reply; 6+ messages in thread From: Andreas Octav @ 2006-10-18 16:02 UTC (permalink / raw) To: LVM general discussion and development Hi, thanks for your response Jonathan, but I want to share the VGs between the hosts. So I hoped that there is something like this functionality: -> "vgimport VG" writes some kind of hostid (system_id?) in the metadata -> other hosts can�t access the VG -> "vgdeport VG" removes the ID, so anyone else can import the VG My C knowledge isn�t very good, but the sources seem to include a functionality like the one mentioned above. Kind regards, Andreas Jonathan E Brassow schrieb: > >>> Hi, >>> >>> i�m new to LVM2 and wondering if it�s possible to restrict access to a >>> Volume Group to a single server (e.g. like under vxvm (vxdg >>> import/deport)). >>> If I import a VG by using vgimport it is still possible to access the >>> VG >>> on another node in a shared SAN environment. Can I prevent this >>> somehow? >>> >>> I�m using lvm2-2.01.14-3.6 on servers running SuSE SLES9 SP3 x86_64. >>> > > You can use tags to achieve this, or you can specify specific volume > groups and logical volumes in lvm.conf under "volume_list". > > brassow > > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! 2006-10-18 16:02 ` Andreas Octav @ 2006-10-18 16:40 ` Jonathan E Brassow 2006-10-18 17:21 ` Andreas Octav 0 siblings, 1 reply; 6+ messages in thread From: Jonathan E Brassow @ 2006-10-18 16:40 UTC (permalink / raw) To: LVM general discussion and development I think it works in the reverse... vgexport adds a generic tag to the volume groups metadata, basically saying "ignore me". Doing a 'vgs' on an exported volume group shows the 'x' attribute; and trying to activate that volume group results in "Volume group "<vgname>" is exported". So, after performing this operation, no-one can use the volume group (until vgimport is run). vgimport removes the generic tag, allowing the VG to be activated and used again. One this command is run, anyone that can see the volume group can use/alter the volume group. Think of it as "import/export from the set of usable volume groups". If you want to share the VGs, you have two options: 1) Use clustered LVM2. This is really the best option. 2) Set up your logical volumes on one machine (you should only use linear or stripe in this scenario - never mirror or snapshot). Never change the logical volume layout after creating it unless the other hosts have deactivated the volume groups being shared. Run 'vgchange -ay' on all machines that have access to the devices. Clustered LVM2 makes sure that all changes to a shared volume group are serialized to prevent corruption and makes sure to activate/deactivate volumes on a cluster-wide basis. If you are never going to change anything (no risk of corruption or inconsistencies), you might be able to get away with using LVM2 as it is. If you need more specialized access, you can use tags. Note, if you are sharing a logical volume, the application (or file system) sharing that volume must be cluster-aware. brassow On Oct 18, 2006, at 11:02 AM, Andreas Octav wrote: > Hi, > > thanks for your response Jonathan, but I want to share the VGs between > the hosts. So I hoped that there is something like this functionality: > -> "vgimport VG" writes some kind of hostid (system_id?) in the > metadata > -> other hosts can�t access the VG > -> "vgdeport VG" removes the ID, so anyone else can import the VG > > My C knowledge isn�t very good, but the sources seem to include a > functionality like the one mentioned above. > > > Kind regards, > Andreas > > Jonathan E Brassow schrieb: >> >>>> Hi, >>>> >>>> i�m new to LVM2 and wondering if it�s possible to restrict access >>>> to a >>>> Volume Group to a single server (e.g. like under vxvm (vxdg >>>> import/deport)). >>>> If I import a VG by using vgimport it is still possible to access >>>> the >>>> VG >>>> on another node in a shared SAN environment. Can I prevent this >>>> somehow? >>>> >>>> I�m using lvm2-2.01.14-3.6 on servers running SuSE SLES9 SP3 x86_64. >>>> >> >> You can use tags to achieve this, or you can specify specific volume >> groups and logical volumes in lvm.conf under "volume_list". >> >> brassow >> >> >> _______________________________________________ >> linux-lvm mailing list >> linux-lvm@redhat.com >> https://www.redhat.com/mailman/listinfo/linux-lvm >> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ >> > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! 2006-10-18 16:40 ` Jonathan E Brassow @ 2006-10-18 17:21 ` Andreas Octav 2006-10-18 17:25 ` Alasdair G Kergon 0 siblings, 1 reply; 6+ messages in thread From: Andreas Octav @ 2006-10-18 17:21 UTC (permalink / raw) To: LVM general discussion and development Sorry, i did not express myself correct: I do not want to share the logical volumes for the use of a Cluster Filesystem (OCFS etc.). I just want to be able to switch the volume groups from one host to another, so only one host at a time has access to a specific volume group. But if I do an vgimport on a host, every host that sees the VG can use it... I am going to install several Oracle/SAP instances in different Volume Groups and I want to be sure that only one host can access a specific VG at a time. The Veritas Volume Manager for example automatically sets a host id of the system that imports a VG (DiskGroup in Veritas terms) during an import, so any other system has to "force" an import, resulting in a loss of access on the former owner. Btw: In LVM1 the system ID is used: ..snip.. vgdisplay VG Name vg vgdisplay System ID PV_IMPKnoppix1077635774 vgdisplay Format lvm1 ..snap.. Is this obsolete in LVM2? Jonathan E Brassow schrieb: > I think it works in the reverse... > > vgexport adds a generic tag to the volume groups metadata, basically > saying "ignore me". Doing a 'vgs' on an exported volume group shows > the 'x' attribute; and trying to activate that volume group results in > "Volume group "<vgname>" is exported". So, after performing this > operation, no-one can use the volume group (until vgimport is run). > > vgimport removes the generic tag, allowing the VG to be activated and > used again. One this command is run, anyone that can see the volume > group can use/alter the volume group. > > Think of it as "import/export from the set of usable volume groups". > > If you want to share the VGs, you have two options: > 1) Use clustered LVM2. This is really the best option. > 2) Set up your logical volumes on one machine (you should only use > linear or stripe in this scenario - never mirror or snapshot). Never > change the logical volume layout after creating it unless the other > hosts have deactivated the volume groups being shared. Run 'vgchange > -ay' on all machines that have access to the devices. > > Clustered LVM2 makes sure that all changes to a shared volume group > are serialized to prevent corruption and makes sure to > activate/deactivate volumes on a cluster-wide basis. If you are > never going to change anything (no risk of corruption or > inconsistencies), you might be able to get away with using LVM2 as it is. > > If you need more specialized access, you can use tags. > > Note, if you are sharing a logical volume, the application (or file > system) sharing that volume must be cluster-aware. > > brassow > > On Oct 18, 2006, at 11:02 AM, Andreas Octav wrote: > >> Hi, >> >> thanks for your response Jonathan, but I want to share the VGs >> between the hosts. So I hoped that there is something like this >> functionality: >> -> "vgimport VG" writes some kind of hostid (system_id?) in the metadata >> -> other hosts can�t access the VG >> -> "vgdeport VG" removes the ID, so anyone else can import the VG >> >> My C knowledge isn�t very good, but the sources seem to include a >> functionality like the one mentioned above. >> >> >> Kind regards, >> Andreas >> >> Jonathan E Brassow schrieb: >>> >>>>> Hi, >>>>> >>>>> i�m new to LVM2 and wondering if it�s possible to restrict access >>>>> to a >>>>> Volume Group to a single server (e.g. like under vxvm (vxdg >>>>> import/deport)). >>>>> If I import a VG by using vgimport it is still possible to access the >>>>> VG >>>>> on another node in a shared SAN environment. Can I prevent this >>>>> somehow? >>>>> >>>>> I�m using lvm2-2.01.14-3.6 on servers running SuSE SLES9 SP3 x86_64. >>>>> >>> >>> You can use tags to achieve this, or you can specify specific volume >>> groups and logical volumes in lvm.conf under "volume_list". >>> >>> brassow >>> >>> >>> _______________________________________________ >>> linux-lvm mailing list >>> linux-lvm@redhat.com >>> https://www.redhat.com/mailman/listinfo/linux-lvm >>> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ >>> >> >> _______________________________________________ >> linux-lvm mailing list >> linux-lvm@redhat.com >> https://www.redhat.com/mailman/listinfo/linux-lvm >> read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ >> > > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ > ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! 2006-10-18 17:21 ` Andreas Octav @ 2006-10-18 17:25 ` Alasdair G Kergon 0 siblings, 0 replies; 6+ messages in thread From: Alasdair G Kergon @ 2006-10-18 17:25 UTC (permalink / raw) To: LVM general discussion and development Try setting hosttags - see man lvm.conf. lvchange --addtag host1 vg1/lv1 lvchange -ay vg1/lv1 lvchange -an vg1/lv1 lvchange --addtag host2 vg1/lv1 lvchange -ay vg1/lv1 Alasdair -- agk@redhat.com ^ permalink raw reply [flat|nested] 6+ messages in thread
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[not found] <1591887.1161167319269.OPEN-XCHANGE.WebMail.wwwrun@eu.main.anykey>
2006-10-18 12:42 ` [linux-lvm] "System ID" entry missing in metadata (LVM2) ?! Andreas Octav
2006-10-18 15:33 ` Jonathan E Brassow
2006-10-18 16:02 ` Andreas Octav
2006-10-18 16:40 ` Jonathan E Brassow
2006-10-18 17:21 ` Andreas Octav
2006-10-18 17:25 ` Alasdair G Kergon
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