>From what kernel / ceph version is krbd usage on a osd node problematic? Currently I am running Nautilus 14.2.11 and el7 3.10 kernel without any issues. I can remember using a cephfs mount without any issues as well, until some specific luminous update surprised me. So maybe nice to know when to expect this. > -----Original Message----- > Sent: Wednesday, 23 June 2021 11:25 > Subject: *****SPAM***** Re: Can not mount rbd device > anymore > > On Wed, Jun 23, 2021 at 9:59 AM Matthias Ferdinand > wrote: > > > > On Tue, Jun 22, 2021 at 02:36:00PM +0200, Ml Ml wrote: > > > Hello List, > > > > > > oversudden i can not mount a specific rbd device anymore: > > > > > > root@proxmox-backup:~# rbd map backup-proxmox/cluster5 -k > > > /etc/ceph/ceph.client.admin.keyring > > > /dev/rbd0 > > > > > > root@proxmox-backup:~# mount /dev/rbd0 /mnt/backup-cluster5/ > > > (just never times out) > > > > > > Hi, > > > > there used to be some kernel lock issues when the kernel rbd client > > tried to access an OSD on the same machine. Not sure if these issues > > still exist (but I would guess so) and if you use your proxmox cluster > > in a hyperconverged manner (nodes providing VMs and storage service at > > the same time) you may just have been lucky that it had worked before. > > > > Instead of the kernel client mount you can try to export the volume as > > an NBD device (https://docs.ceph.com/en/latest/man/8/rbd-nbd/) and > > mounting that. rbd-nbd runs in userspace and should not have that > > locking problem. > > rbd-nbd is also susceptible to locking up in such setups, likely more > so than krbd. Don't forget that it also has a kernel component and > there are actually more opportunities for things to go sideways/lock up > because there is an extra daemon involved allocating some additional > memory for each I/O request. > > Thanks, > > Ilya > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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