Windows 2012 Server Backup failure with SMB >= 2.1 (FSCTL_LMR_REQUEST_RESILIENCY)
Stefan (metze) Metzmacher
metze at samba.org
Fri Nov 15 02:30:10 MST 2013
Am 15.11.2013 10:17, schrieb Jones:
> Hi List,
> The client OS is Windows Server 2012,
> and Windows Server Backup is installed from Server Manager.
> The short "WSB" stands for Windows Server Backup in this article.
> Trying to perform a single backup to remote shared folder,
> which is a location specified on a Samba3/4 server,
> or a Widnows 7 PC as comparison.
> If WSB is success.
> data transferred size is total around 14GB.
> If WSB is failure,
> log-level-10 message is saved as samba-4.0.5_windows_server_backup_log.smbd,
> and wireshark pcap file as samba-4.0.5_windows_server_backup.pcap.
> Here are detailed test results:
> (A) Server: Samba-3.6.18
> While max protocol =
> (A.1) NT1, WSB is success.
> (A.2) SMB2, WSB is success.
> (B) Server: Samba-4.0.5
> While max protocol =
> (B.1) NT1, WSB is success.
> (B.2) SMB2_02, WSB is success.
> (B.3) SMB2_10, WSB is failure.
> (B.4) SMB3_00, WSB is failure.
> (C) Server: Windows 7 Home Premium 64bit
> The negotiated protocol is SMB 2.1 (thru wireshark dialect: 0x210),
> and WSB is always success.
> (D) FSCTL_LMR_REQUEST_RESILIENCY is involved with SMB >= 2.1
> During WSB is launched,
> while Windows Server 2012 and Samba are negotiated with SMB >= 2.1,
> the client would issue an additional ioctl request,
> with CtlCode = FSCTL_LMR_REQUEST_RESILIENCY.
> Samba would fail this request with STATUS_INVALID_DEVICE_REQUEST,
> but Windows 7 could handle it well with STATUS_SUCCESS response.
> (E) Questions
> In short summary,
> While Windows Server 2012 and Samba are negotiated with SMB >= 2.1,
> WSB is always failure.
> Is FSCTL_LMR_REQUEST_RESILIENCY the failure cause?
> Is there a tricky method or magic flag to avoid client issue this fsctl,
> or instead,
> just made SMB <= 2.0 happened between client and server to avoid this fsctl?
> Is this fsctl is kindly put into consideration @ Samba.Org,
> or is it already in progress or developing roadmap?
> Any suggestion is appreciated,
> (F) Bugzilla 9938, 10055
> Found similar symptom in following links,
> WSB would create a .vhdx file like #9938.
> (G) Mailing list
> It is likely FSCTL_LMR_REQUEST_RESILIENCY is not implemented yet.
> (H) Wiki Samba3/SMB2
> TODO: resilient file handles, persistent file handles
> (I) Microsoft MSDN, Handling a Resiliency Request
> Said: This section applies only to servers that implement the SMB 2.1 or
> the SMB 3.x dialect family.
Maybe we just need to return NT_STATUS_NOT_SUPPORTED instead of
NT_STATUS_INVALID_DEVICE_REQUEST? In order to match
[MS-SMB2] 220.127.116.11.9 Handling a Resiliency Request
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