Re: [ovirt-users] storage issue's with oVirt 3.5.1 + Nexenta NFS

On Wed, 2015-04-22 at 11:12 +0200, Maikel vd Mosselaar wrote: > Our pool is configured as Z1 with ZIL (normal SSD), the sync parameter > is on the default setting (standard) so "sync" is on. # zpool status ? /K > When the issue happens oVirt event viewer shows indeed latency warnings. > Not always but most of the time this will be followed by an i/o storage > error linked to random VMs and they will be paused when that happens. > > All the nodes use mode 4 bonding. The interfaces on the nodes don't show > any drops or errors, i checked 2 of the VMs that got paused the last > time it happened they have dropped packets on their interfaces. > > We don't have a subscription with nexenta (anymore). > > On 04/21/2015 04:41 PM, InterNetX - Juergen Gotteswinter wrote: >> Am 21.04.2015 um 16:19 schrieb Maikel vd Mosselaar: >>> Hi Juergen, >>> >>> The load on the nodes rises far over >200 during the event. Load on the >>> nexenta stays normal and nothing strange in the logging. >> ZFS + NFS could be still the root of this. Your Pool Configuration is >> RaidzX or Mirror, with or without ZIL? The sync Parameter of your ZFS >> Subvolume which gets exported is kept default on "standard" ? >> >> http://christopher-technicalmusings.blogspot.de/2010/09/zfs-and-nfs-perfo... >> >> Since Ovirt acts very sensible about Storage Latency (throws VM into >> unresponsive or unknown state) it might be worth a try to do "zfs set >> sync=disabled pool/volume" to see if this changes things. But be aware >> that this makes the NFS Export vuln. against dataloss in case of >> powerloss etc, comparable to async NFS in Linux. >> >> If disabling the sync setting helps, and you dont use a seperate ZIL >> Flash Drive yet -> this whould be very likely help to get rid of this. >> >> Also, if you run a subscribed Version of Nexenta it might be helpful to >> involve them. >> >> Do you see any messages about high latency in the Ovirt Events Panel? >> >>> For our storage interfaces on our nodes we use bonding in mode 4 >>> (802.3ad) 2x 1Gb. The nexenta has 4x 1Gb bond in mode 4 also. >> This should be fine, as long as no Node uses Mode0 / Round Robin which >> whould lead to out of order TCP Packets. The Interfaces themself dont >> show any Drops or Errors - on the VM Hosts as well as on the Switch itself? >> >> Jumbo Frames? >> >>> Kind regards, >>> >>> Maikel >>> >>> >>> On 04/21/2015 02:51 PM, InterNetX - Juergen Gotteswinter wrote: >>>> Hi, >>>> >>>> how about Load, Latency, strange dmesg messages on the Nexenta ? You are >>>> using bonded Gbit Networking? If yes, which mode? >>>> >>>> Cheers, >>>> >>>> Juergen >>>> >>>> Am 20.04.2015 um 14:25 schrieb Maikel vd Mosselaar: >>>>> Hi, >>>>> >>>>> We are running ovirt 3.5.1 with 3 nodes and seperate engine. >>>>> >>>>> All on CentOS 6.6: >>>>> 3 x nodes >>>>> 1 x engine >>>>> >>>>> 1 x storage nexenta with NFS >>>>> >>>>> For multiple weeks we are experiencing issues of our nodes that cannot >>>>> access the storage at random moments (atleast thats what the nodes >>>>> think). >>>>> >>>>> When the nodes are complaining about a unavailable storage then the load >>>>> rises up to +200 on all three nodes, this causes that all running VMs >>>>> are unaccessible. During this process oVirt event viewer shows some i/o >>>>> storage error messages, when this happens random VMs get paused and will >>>>> not be resumed anymore (this almost happens every time but not all the >>>>> VMs get paused). >>>>> >>>>> During the event we tested the accessibility from the nodes to the >>>>> storage and it looks like it is working normal, at least we can do a >>>>> normal >>>>> "ls" on the storage without any delay of showing the contents. >>>>> >>>>> We tried multiple things that we thought it causes this issue but >>>>> nothing worked so far. >>>>> * rebooting storage / nodes / engine. >>>>> * disabling offsite rsync backups. >>>>> * moved the biggest VMs with highest load to different platform outside >>>>> of oVirt. >>>>> * checked the wsize and rsize on the nfs mounts, storage and nodes are >>>>> correct according to the "NFS troubleshooting page" on ovirt.org. >>>>> >>>>> The environment is running in production so we are not free to test >>>>> everything. >>>>> >>>>> I can provide log files if needed. >>>>> >>>>> Kind Regards, >>>>> >>>>> Maikel >>>>> >>>>> >>>>> _______________________________________________ >>>>> Users mailing list >>>>> Users(a)ovirt.org >>>>> http://lists.ovirt.org/mailman/listinfo/users >>>> _______________________________________________ >>>> Users mailing list >>>> Users(a)ovirt.org >>>> http://lists.ovirt.org/mailman/listinfo/users > _______________________________________________ > Users mailing list > Users(a)ovirt.org > http://lists.ovirt.org/mailman/listinfo/users _______________________________________________ Users mailing list Users(a)ovirt.org http://lists.ovirt.org/mailman/listinfo/users