Re: Real Device with BHyve
Forgive me, but I can't understand what you mean. Are we talking of using something like /dev/cciss (just to say...) instead of /dev/da2 as the device shared with the VM? Won't the VM and the real system clash in using the same device? On Thu, Jan 2, 2014 at 9:29 PM, Nikolai Lifanov lifa...@mail.lifanov.comwrote: On 01/02/14 15:22, freebsd-virtualization-requ...@freebsd.org wrote: Hello everybody. I'm doing some experiments with bhyve on 10.0-RC3 and I got stuck at a certain point. I was trying to have a VM use a direct device (/dev/da2) instead of a disk image. I was trying it in order to understand if there was any real performance difference between using a raw drive or an image-disk on the same drive. Well, the machine starts ok but when the child FreeBSD starts installation something strange happens. When I get to the partitioning screen I can see the device avaiable as /dev/vtdb0 with the correct size and such. I choose autopartitioning, the installer writes the partition table but when it start to write /dev/vtdb0p2 a very cryptic error appears about being unable to write - sorry, did not write it down. The installer then stops. If I do a fdisk /dev/vtdb0 in the VM I can see the GPT partition being there. If I do a fdisk /dev/da2 on the host machine, I can see the GPT partition as well, but the VM just doesn't want to write on it. I even tried changing kern.geom.debugflags=16 as I thought the host machine could be locking somehow the drive, but that didn't seem to make any difference. I know it was a lame check but I was out of ideas. So I just wanted to understand if such a scenario is supposed to be supported What I was thinking of, for example, was of having an external iSCSI device connected on the hostmachine mapped as a virtual disk for a specific VM, in order to speed the VM disk performances. Just another quick question... I have seen some improvements by having the VM's virtual disk on ZFS against UFS. Is it just me or is there any real improvement by using ZFS? Thanks a lot. -- *Andrea BrancatelliSchema 31 S.r.l. - Socio UnicoResponsabile ITROMA - FIRENZE - PALERMO ITALYTel: +39. 06.98.358.472* *Cell: +39 331.2488468Fax: +39. 055.71.880.466Societ? del Gruppo SC31 ITALIA* I'm not answering your question precisely, but can you pass through the disk controller to the virtual machine instead? I also know that zvol and iscsi backends work, at least the last time I checked. - Nikolai Lifanov ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org -- *Andrea BrancatelliSchema 31 S.r.l. - Socio UnicoResponsabile ITROMA - FIRENZE - PALERMO ITALYTel: +39. 06.98.358.472* *Cell: +39 331.2488468Fax: +39. 055.71.880.466Società del Gruppo SC31 ITALIA* ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: Real Device with BHyve
Hi Andrea, Well, the machine starts ok but when the child FreeBSD starts installation something strange happens. When I get to the partitioning screen I can see the device avaiable as /dev/vtdb0 with the correct size and such. I choose autopartitioning, the installer writes the partition table but when it start to write /dev/vtdb0p2 a very cryptic error appears about being unable to write - sorry, did not write it down. The installer then stops. If I do a fdisk /dev/vtdb0 in the VM I can see the GPT partition being there. If I do a fdisk /dev/da2 on the host machine, I can see the GPT partition as well, but the VM just doesn't want to write on it. I even tried changing kern.geom.debugflags=16 as I thought the host machine could be locking somehow the drive, but that didn't seem to make any difference. I know it was a lame check but I was out of ideas. So I just wanted to understand if such a scenario is supposed to be supported It is. Been a while since I've done this but will try a repro. Other folk have supported success using zvols so I'd assumed it was working. What I was thinking of, for example, was of having an external iSCSI device connected on the hostmachine mapped as a virtual disk for a specific VM, in order to speed the VM disk performances. Yes, that's one of the scenarios in mind. Just another quick question... I have seen some improvements by having the VM's virtual disk on ZFS against UFS. Is it just me or is there any real improvement by using ZFS? Difficult question to answer - probably workload-dependent. later, Peter. ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: Real Device with BHyve
On Fri, 03 Jan 2014 09:43:24 -0800 Peter Grehan gre...@freebsd.org wrote: Hi Andrea, Well, the machine starts ok but when the child FreeBSD starts installation something strange happens. When I get to the partitioning screen I can see the device avaiable as /dev/vtdb0 with the correct size and such. I choose autopartitioning, the installer writes the partition table but when it start to write /dev/vtdb0p2 a very cryptic error appears about being unable to write - sorry, did not write it down. The installer then stops. If I do a fdisk /dev/vtdb0 in the VM I can see the GPT partition being there. If I do a fdisk /dev/da2 on the host machine, I can see the GPT partition as well, but the VM just doesn't want to write on it. I even tried changing kern.geom.debugflags=16 as I thought the host machine could be locking somehow the drive, but that didn't seem to make any difference. I know it was a lame check but I was out of ideas. So I just wanted to understand if such a scenario is supposed to be supported It is. Been a while since I've done this but will try a repro. Other folk have supported success using zvols so I'd assumed it was working. If it helps, I had the same problem using zvol as well (booting the installer and install on the raw device) on 10-CURRENT from mid 2013. I didn't try with a more recent release. I ended up installing FreeBSD from the outside (create partitions and untar base.txz, kernel.txz etc. - afaik the same thing the Dexter's vm0 script does now) and could then boot into it just fine. -- Michael Gmelin ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
Re: Real Device with BHyve
On 01/02/14 15:22, freebsd-virtualization-requ...@freebsd.org wrote: Hello everybody. I'm doing some experiments with bhyve on 10.0-RC3 and I got stuck at a certain point. I was trying to have a VM use a direct device (/dev/da2) instead of a disk image. I was trying it in order to understand if there was any real performance difference between using a raw drive or an image-disk on the same drive. Well, the machine starts ok but when the child FreeBSD starts installation something strange happens. When I get to the partitioning screen I can see the device avaiable as /dev/vtdb0 with the correct size and such. I choose autopartitioning, the installer writes the partition table but when it start to write /dev/vtdb0p2 a very cryptic error appears about being unable to write - sorry, did not write it down. The installer then stops. If I do a fdisk /dev/vtdb0 in the VM I can see the GPT partition being there. If I do a fdisk /dev/da2 on the host machine, I can see the GPT partition as well, but the VM just doesn't want to write on it. I even tried changing kern.geom.debugflags=16 as I thought the host machine could be locking somehow the drive, but that didn't seem to make any difference. I know it was a lame check but I was out of ideas. So I just wanted to understand if such a scenario is supposed to be supported What I was thinking of, for example, was of having an external iSCSI device connected on the hostmachine mapped as a virtual disk for a specific VM, in order to speed the VM disk performances. Just another quick question... I have seen some improvements by having the VM's virtual disk on ZFS against UFS. Is it just me or is there any real improvement by using ZFS? Thanks a lot. -- *Andrea BrancatelliSchema 31 S.r.l. - Socio UnicoResponsabile ITROMA - FIRENZE - PALERMO ITALYTel: +39. 06.98.358.472* *Cell: +39 331.2488468Fax: +39. 055.71.880.466Societ? del Gruppo SC31 ITALIA* I'm not answering your question precisely, but can you pass through the disk controller to the virtual machine instead? I also know that zvol and iscsi backends work, at least the last time I checked. - Nikolai Lifanov ___ freebsd-virtualization@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-virtualization To unsubscribe, send any mail to freebsd-virtualization-unsubscr...@freebsd.org
