Bug 998710
| Summary: | Add LVM support for /boot. | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Alasdair Kergon <agk> | |
| Component: | lvm2 | Assignee: | Peter Rajnoha <prajnoha> | |
| lvm2 sub component: | Activating existing Logical Volumes | QA Contact: | cluster-qe <cluster-qe> | |
| Status: | CLOSED WONTFIX | Docs Contact: | ||
| Severity: | low | |||
| Priority: | medium | CC: | adshaikh, agk, amote, aperotti, baumanmo, bmarzins, bmr, chorn, christoph.karl, coughlan, dconsoli, dlehman, dwysocha, heinzm, jbrassow, jonathan, loberman, lsmid, lvm-team, mrichter, msnitzer, mthacker, ngompa13, pablo.iranzo, pdwyer, prajnoha, prockai, robine, rvdwees, rvokal, tbowling, vanhoof, zkabelac | |
| Version: | 7.0 | Keywords: | FutureFeature, Triaged | |
| Target Milestone: | rc | |||
| Target Release: | 7.3 | |||
| Hardware: | All | |||
| OS: | All | |||
| Whiteboard: | ||||
| Fixed In Version: | Doc Type: | Enhancement | ||
| Doc Text: | Story Points: | --- | ||
| Clone Of: | 872576 | |||
| : | 1243449 (view as bug list) | Environment: | ||
| Last Closed: | 2017-07-26 14:42:39 UTC | Type: | --- | |
| Regression: | --- | Mount Type: | --- | |
| Documentation: | --- | CRM: | ||
| Verified Versions: | Category: | --- | ||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | ||
| Cloudforms Team: | --- | Target Upstream Version: | ||
| Embargoed: | ||||
| Bug Depends On: | 760243, 760258, 1496229 | |||
| Bug Blocks: | 1164947, 794823, 1008418, 1205796, 1243449, 1298243, 1411715, 1469559 | |||
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Description
Alasdair Kergon
2013-08-19 20:28:32 UTC
Would like to see this as well. Also, would this be an enabler for other activities such as booting from a snapshot with a grub menu item? This would be a great feature allowing RHEL 7 to use only LVM and no old-school partitions. This would provide much greater flexibility with disk imaging and our own RHEL cloud images which currently do not use lvm for /dev/sda. So if I deploy a cloud image, I cannot easily resize the disk limiting my flexibility in use the cloud image as a gold image foundation for my deployments. Deferring to RHEL 7.5. > This would provide much greater flexibility with disk imaging and our own RHEL
> cloud images which currently do not use lvm for /dev/sda. So if I deploy a
> cloud image, I cannot easily resize the disk limiting my flexibility in use the
> cloud image as a gold image foundation for my deployments.
I can understand the limitation here, in terms of conventional partitions not allowing straightforward resize, but it's not quite clear to me why being able to place /boot on LVM2 would fix it?
What's the restriction that prevents the cloud images from using LVM devices on sda in this scenario? (with a conventional partition for /boot as in a regular installation).
We would like to add more boot time features, like booting to a snapshot (or group of snapshots); but eliminating /boot is a tall order - especially with UEFI booting. This may never happen and certainly won't happen in RHEL7. Currently I need two block devices to setup a VM. One as a PV for LVM (without partioning for resize reasoning) and one only for /boot. Would be a bit easier, if I only need one block device per VM. (In reply to Christoph Karl from comment #16) > Currently I need two block devices to setup a VM. > One as a PV for LVM (without partioning for resize reasoning) and one only > for /boot. > Would be a bit easier, if I only need one block device per VM. RHEL7 and 8 can still be installed with "everything on one partition", I think you are referring to that. $ cat /proc/partitions major minor #blocks name 253 0 150994944 vda 253 1 8388608 vda1 11 0 1048575 sr0 Currently I have: >lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vda 252:0 0 1G 0 disk └─vda1 252:1 0 1023M 0 part /boot vdb 252:16 0 50G 0 disk ├─rhel-root 253:0 0 40G 0 lvm / └─rhel-lvlogs 253:1 0 2G 0 lvm /logs Two block devices: vda und vdb. The PV on vdb must be without partitioning so I can resize the PV. I want to have: >lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vda 252:0 0 50G 0 disk ├─rhel-root 253:0 0 40G 0 lvm / └─rhel-lvlogs 253:1 0 2G 0 lvm /logs Only one block device: vda Reasoning: *) Only one block device per VM *) I can online-resize any filesystem in this VM This would also be OK:
>lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
vda 252:0 0 50G 0 disk
├─rhel-root 253:0 0 40G 0 lvm /
├─rhel-boot 253:1 0 1023M 0 lvm /boot
└─rhel-lvlogs 253:2 0 2G 0 lvm /logs
Both of the variants you aim at have /boot on LVM, which will for the time being not become supported, the bugzilla state reflects this. The next best thing for you might be: - to have a single blockdevice into the guest - to have /boot on a partition (which is not resizable in very flexible ways, so the size should be chosen carefully) - to have a further partition, and inside LVM. In case you extend the blockdevice in the future, you can just add a further partition and use it to extend the VG. Alternatively, you can consider to extend the partition and resize the existing PV. $ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vda 252:0 0 72G 0 disk ├─vda1 252:1 0 1G 0 part /boot └─vda2 252:2 0 71G 0 part └─rhel_rhel8u2b-root 253:0 0 45G 0 lvm / AFAIK "adding further partitions" and "extending a partition" are not supported: https://access.redhat.com/solutions/199573 I see this as a feature request not as a bug report. Currently I stick to two block devices. I think the bugzilla refers to resizing of a partition which is in use. Following 2 variants should still be open: - If really / of the guest should be resized (low chances this is required, I think), then one could boot a rescue system and do an offline resize of the partition. - When the underlying blockdevice got enlarged, one could still add an additional partition, use pvcreate, extend an LVM volume and with this take usage of the additional space |