[ovirt-devel] Re: [ovirt-users] Re: [=EXTERNAL=] Re: help using nvme/tcp storage with cinderlib and Managed Block Storage

Thanks for the detailed instructions, Nir. I'm going to scrounge up some hardware. By the way, if anyone else would like to work on NVMe/TCP support, for NVMe/TCP target you can either use Lightbits (talk to me offline for details) or use the upstream Linux NVMe/TCP target. Lightbits is a clustered storage system while upstream is a single target, but the client side should be close enough for vdsm/ovirt purposes.

Cheers, Muli -- Muli Ben-Yehuda Co-Founder and Chief Scientist @ http://www.lightbitslabs.com LightOS: The Special Storage Sauce For Your Cloud On Wed, Feb 23, 2022 at 4:55 PM Nir Soffer <nsoffer(a)redhat.com&gt; wrote: > > On Wed, Feb 23, 2022 at 4:20 PM Muli Ben-Yehuda <muli(a)lightbitslabs.com&gt; wrote: > > > > Thanks, Nir and Benny (nice to run into you again, Nir!). I'm a neophyte in ovirt and vdsm... What's the simplest way to set up a development environment? Is it possible to set up a "standalone" vdsm environment to hack support for nvme/tcp or do I need "full ovirt" to make it work? > > It should be possible to install vdsm on a single host or vm, and use vdsm > API to bring the host to the right state, and then attach devices and run > vms. But I don't know anyone that can pull this out since simulating what > engine is doing is hard. > > So the best way is to set up at least one host and engine host using the > latest 4.5 rpms, and continue from there. Once you have a host, building > vdsm on the host and upgrading the rpms is pretty easy. > > My preferred setup is to create vms using virt-manager for hosts, engine > and storage and run all the vms on my laptop. > > Note that you must have some traditional storage (NFS/iSCSI) to bring up > the system even if you plan to use only managed block storage (MBS). > Unfortunately when we add MBS support we did have time to fix the huge > technical debt so you still need a master storage domain using one of the > traditional legacy options. > > To build a setup, you can use: > > - engine vm: 6g ram, 2 cpus, centos stream 8 > - hosts vm: 4g ram, 2 cpus, centos stream 8 > you can start with one host and add more hosts later if you want to > test migration. > - storage vm: 2g ram, 2 cpus, any os you like, I use alpine since it > takes very little > memory and its NFS server is fast. > > See vdsm README for instructions how to setup a host: > https://github.com/oVirt/vdsm#manual-installation > > For engine host you can follow: > https://ovirt.org/documentation/installing_ovirt_as_a_self-hosted_engine_... > > And after that this should work: > > dnf install ovirt-engine > engine-setup > > Accepting all the defaults should work. > > When you have engine running, you can add a new host with > the ip address or dns name of you host(s) vm, and engine will > do everything for you. Note that you must install the ovirt-release-master > rpm on the host before you add it to engine. > > Nir > > > > > Cheers, > > Muli > > -- > > Muli Ben-Yehuda > > Co-Founder and Chief Scientist @ http://www.lightbitslabs.com > > LightOS: The Special Storage Sauce For Your Cloud > > > > > > On Wed, Feb 23, 2022 at 4:16 PM Nir Soffer <nsoffer(a)redhat.com&gt; wrote: > >> > >> On Wed, Feb 23, 2022 at 2:48 PM Benny Zlotnik <bzlotnik(a)redhat.com&gt; wrote: > >> > > >> > So I started looking in the logs and tried to follow along with the > >> > code, but things didn't make sense and then I saw it's ovirt 4.3 which > >> > makes things more complicated :) > >> > Unfortunately because GUID is sent in the metadata the volume is > >> > treated as a vdsm managed volume[2] for the udev rule generation and > >> > it prepends the /dev/mapper prefix to an empty string as a result. > >> > I don't have the vdsm logs, so I am not sure where exactly this fails, > >> > but if it's after [4] it may be possible to workaround it with a vdsm > >> > hook > >> > > >> > In 4.4.6 we moved the udev rule triggering the volume mapping phase, > >> > before starting the VM. But it could still not work because we check > >> > the driver_volume_type in[1], and I saw it's "driver_volume_type": > >> > "lightos" for lightbits > >> > In theory it looks like it wouldn't take much to add support for your > >> > driver in a future release (as it's pretty late for 4.5) > >> > >> Adding support for nvme/tcp in 4.3 is probably not feasible, but we will > >> be happy to accept patches for 4.5. > >> > >> To debug such issues vdsm log is the best place to check. We should see > >> the connection info passed to vdsm, and we have pretty simple code using > >> it with os_brick to attach the device to the system and setting up the udev > >> rule (which may need some tweaks). > >> > >> Nir > >> > >> > [1] https://github.com/oVirt/vdsm/blob/500c035903dd35180d71c97791e0ce4356fb77... > >> > > >> > (4.3) > >> > [2] https://github.com/oVirt/vdsm/blob/b42d4a816b538e00ea4955576a5fe762367be7... > >> > [3] https://github.com/oVirt/vdsm/blob/b42d4a816b538e00ea4955576a5fe762367be7... > >> > [4] https://github.com/oVirt/vdsm/blob/b42d4a816b538e00ea4955576a5fe762367be7... > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > On Wed, Feb 23, 2022 at 12:44 PM Muli Ben-Yehuda <muli(a)lightbitslabs.com&gt; wrote: > >> > > > >> > > Certainly, thanks for your help! > >> > > I put cinderlib and engine.log here: http://www.mulix.org/misc/ovirt-logs-20220223123641.tar.gz > >> > > If you grep for 'mulivm1' you will see for example: > >> > > > >> > > 2022-02-22 04:31:04,473-05 ERROR [org.ovirt.engine.core.vdsbroker.vdsbroker.HotPlugDiskVDSCommand] (default task-10) [36d8a122] Command 'HotPlugDiskVDSCommand(HostName = client1, HotPlugDiskVDSParameters:{hostId='fc5c2860-36b1-4213-843f-10ca7b35556c', vmId='e13f73a0-8e20-4ec3-837f-aeacc082c7aa', diskId='d1e1286b-38cc-4d56-9d4e-f331ffbe830f', addressMap='[bus=0, controller=0, unit=2, type=drive, target=0]'})' execution failed: VDSGenericException: VDSErrorException: Failed to HotPlugDiskVDS, error = Failed to bind /dev/mapper/ on to /var/run/libvirt/qemu/21-mulivm1.mapper.: Not a directory, code = 45 > >> > > > >> > > Please let me know what other information will be useful and I will prove. > >> > > > >> > > Cheers, > >> > > Muli > >> > > > >> > > On Wed, Feb 23, 2022 at 11:14 AM Benny Zlotnik <bzlotnik(a)redhat.com&gt; wrote: > >> > >> > >> > >> Hi, > >> > >> > >> > >> We haven't tested this, and we do not have any code to handle nvme/tcp > >> > >> drivers, only iscsi and rbd. Given the path seen in the logs > >> > >> '/dev/mapper', it looks like it might require code changes to support > >> > >> this. > >> > >> Can you share cinderlib[1] and engine logs to see what is returned by > >> > >> the driver? I may be able to estimate what would be required (it's > >> > >> possible that it would be enough to just change the handling of the > >> > >> path in the engine) > >> > >> > >> > >> [1] /var/log/ovirt-engine/cinderlib/cinderlib//log > >> > >> > >> > >> On Wed, Feb 23, 2022 at 10:54 AM <muli(a)lightbitslabs.com&gt; wrote: > >> > >> > > >> > >> > Hi everyone, > >> > >> > > >> > >> > We are trying to set up ovirt (4.3.10 at the moment, customer preference) to use Lightbits (https://www.lightbitslabs.com) storage via our openstack cinder driver with cinderlib. The cinderlib and cinder driver bits are working fine but when ovirt tries to attach the device to a VM we get the following error: > >> > >> > > >> > >> > libvirt: error : cannot create file '/var/run/libvirt/qemu/18-mulivm1.dev/mapper/': Is a directory > >> > >> > > >> > >> > We get the same error regardless of whether I try to run the VM or try to attach the device while it is running. The error appears to come from vdsm which passes /dev/mapper as the prefered device? > >> > >> > > >> > >> > 2022-02-22 09:50:11,848-0500 INFO (vm/3ae7dcf4) [vdsm.api] FINISH appropriateDevice return={'path': '/dev/mapper/', 'truesize': '53687091200', 'apparentsize': '53687091200'} from=internal, task_id=77f40c4e-733d-4d82-b418-aaeb6b912d39 (api:54) > >> > >> > 2022-02-22 09:50:11,849-0500 INFO (vm/3ae7dcf4) [vds] prepared volume path: /dev/mapper/ (clientIF:510) > >> > >> > > >> > >> > Suggestions for how to debug this further? Is this a known issue? Did anyone get nvme/tcp storage working with ovirt and/or vdsm? > >> > >> > > >> > >> > Thanks, > >> > >> > Muli > >> > >> > > >> > >> > _______________________________________________ > >> > >> > Users mailing list -- users(a)ovirt.org > >> > >> > To unsubscribe send an email to users-leave(a)ovirt.org > >> > >> > Privacy Statement: https://www.ovirt.org/privacy-policy.html > >> > >> > oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ > >> > >> > List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/I3PAG5HMBHU... > >> > >> > >> > > > >> > > Lightbits Labs > >> > > Lead the cloud-native data center transformation by delivering scalable and efficient software defined storage that is easy to consume. > >> > > > >> > > This message is sent in confidence for the addressee only. It may contain legally privileged information. The contents are not to be disclosed to anyone other than the addressee. Unauthorized recipients are requested to preserve this confidentiality, advise the sender immediately of any error in transmission and delete the email from their systems. > >> > > > >> > > > >> > _______________________________________________ > >> > Users mailing list -- users(a)ovirt.org > >> > To unsubscribe send an email to users-leave(a)ovirt.org > >> > Privacy Statement: https://www.ovirt.org/privacy-policy.html > >> > oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ > >> > List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/DKFOCYQA6E4... > >> > > > > Lightbits Labs > > Lead the cloud-native data center transformation by delivering scalable and efficient software defined storage that is easy to consume. > > > > This message is sent in confidence for the addressee only. It may contain legally privileged information. The contents are not to be disclosed to anyone other than the addressee. Unauthorized recipients are requested to preserve this confidentiality, advise the sender immediately of any error in transmission and delete the email from their systems. > > > > > Lightbits Labs Lead the cloud-native data center transformation by delivering scalable and efficient software defined storage that is easy to consume. This message is sent in confidence for the addressee only. It may contain legally privileged information. The contents are not to be disclosed to anyone other than the addressee. Unauthorized recipients are requested to preserve this confidentiality, advise the sender immediately of any error in transmission and delete the email from their systems.