@decui Regarding downgrade, I think I might not have been clear on this. The downgrade occurs only when there are backups running. Our performance otherwise is great. This (new) problem is not necessarily related to this specific issue, but more to backups on Hyper-V in general. Nonetheless, as I stated earlier, the problem is limiting us (even further) when and how many backups we are creating. This is far from an idealistic situation.
As I said, the cause of this problem might be occupied disk space. We have not changed anything else on our platform or setup, other than running the usual apt-get upgrades. Further, please see comment #47 where another user made a similar comment regarding performance downgrade. Maybe it is better if I create a separate bug report for this issue. Finally, regarding the downgrade issue, I am also prepared to provide access to our machines to employees of Microsoft and Ubuntu, if required. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1470250 Title: [Hyper-V] Ubuntu 14.04.2 LTS Generation 2 SCSI Errors on VSS Based Backups Status in linux package in Ubuntu: In Progress Status in linux source package in Trusty: In Progress Status in linux source package in Utopic: In Progress Status in linux source package in Vivid: In Progress Status in linux source package in Wily: In Progress Bug description: Customers have reported running various versions of Ubuntu 14.04.2 LTS on Generation 2 Hyper-V Hosts. On a random Basis, the file system will be mounted Read-Only due to a "disk error" (which really isn't the case here). As a result, they must reboot the Ubuntu guest to get the file system to mount RW again. The Error seen are the following: Apr 30 00:02:01 balticnetworkstraining kernel: [640153.968142] storvsc: Sense Key : Unit Attention [current] Apr 30 00:02:01 balticnetworkstraining kernel: [640153.968145] storvsc: Add. Sense: Changed operating definition Apr 30 00:02:01 balticnetworkstraining kernel: [640153.968161] sd 0:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters. Apr 30 01:23:26 balticnetworkstraining kernel: [645039.584164] hv_storvsc vmbus_0_4: cmd 0x2a scsi status 0x2 srb status 0x82 Apr 30 01:23:26 balticnetworkstraining kernel: [645039.584178] hv_storvsc vmbus_0_4: stor pkt ffff88006eb6c700 autosense data valid - len 18 Apr 30 01:23:26 balticnetworkstraining kernel: [645039.584180] storvsc: Sense Key : Unit Attention [current] Apr 30 01:23:26 balticnetworkstraining kernel: [645039.584183] storvsc: Add. Sense: Changed operating definition Apr 30 01:23:26 balticnetworkstraining kernel: [645039.584198] sd 0:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters. This relates to the VSS "Windows Server Backup" process that kicks off at midnight on the host and finishes an hour and half later. Yes, we do have hv_vss_daemon and hv_kvp_daemon running for the correct kernel version we have. We're currently running kernel version 3.13.0-49-generic #83 on one system and 3.16.0-34-generic #37 on the other. -- We see the same errors on both. As a result, we've been hesitant to drop any more ubuntu guests on our 2012R2 hyper-v system because of this. We can stop the backup process and all is good, but we need nightly backups to image all of our VM's. All the windows guests have no issues of course. We also have some CentOS based guests running without issues from what we've seen. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1470250/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp