[Samba] 答复: status of Continuous availability in SMB3

[zhengbin.08747 at h3c.com]

hi Michael
Thank you for you quick reply. ^-^
Is CA development on the schedule or some kind gays are working on it now? If not, we plan to do some work about it and we need estimate the workload. We need you advice about how many lines of code needs to have CA implemented. Thanks again.

weidong

-----邮件原件-----
发件人: Michael Adam [mailto:obnox at samba.org]
发送时间: 2016年8月31日 16:30
收件人: zhengbin 08747 (RD)
抄送: weidong 12656 (RD); 'samba at lists.samba.org'
主题: Re: status of Continuous availability in SMB3

On 2016-08-31 at 08:13 +0000, zhengbin.08747 at h3c.com wrote:
> hi Michael Adam:
> Thanks for you work on samba. Here I am looking for some advice and your help.
> I have been stuck in continuous availability of samba 4.3.9 for two weeks. Continuous availability in SMB3 is an attractive feature and I am strugling to enable it.
>
> smb.conf, ctdb.conf are attached. Cluster file system is cephfs and
> mount to /CephStorage
>
> client: Windows 8 Pro
>
> root at node0:~# samba --version
> Version 4.3.9-Ubuntu
>
> root at node0:~# ctdb version
> CTDB version: 2.5.1
>
> root at node0:~# ctdb status
> Number of nodes:3
> pnn:0 192.168.74.11    OK (THIS NODE)
> pnn:1 192.168.74.12    OK
> pnn:2 192.168.74.13    OK
> Generation:1131631460
> Size:3
> hash:0 lmaster:0
> hash:1 lmaster:1
> hash:2 lmaster:2
> Recovery mode:NORMAL (0)
> Recovery master:0
>
> root at node0:~# ctdb ip
> Public IPs on node 0
> 192.168.74.20 0
>
>
>
> My test procedure is as below.
> 1. The virtual IP is holded by onde0(192.168.74.11). Client(Win 8) accesses \\192.168.74.20\<file:///\\192.168.74.20\>. Copy a large file out of the remote dir and make sure the operation taking a period of time.
> 2. Restart the ctdb process on node0 to force virtual IP to be taken over by node1(192.168.74.12).
> 3. At the moment the virtual IP is taken by node1, the copy operation is interrupted simultaneously and can not continue the operation without re-copy the whole file.
>
> When carring out the test, I have a wireshark process run. It is confirmed that protocol smb3 is used. In the tree connection phase, server's response to client claims that it does not support DFS/Continuous Availability.
> I'm confused that does SMB3 protocol in samba 4.3.9 just been partly implemented and CA is of one the feature unspported by this version of samba. Or I have not found the way to enable the CA feature. Look forward to your kind advice.

It is true that to date, CA is not implemented in Samba.
The SMB2 and SMB3 protocols have a number of capabilities that are optional in the sense that the server tells the client whether it supports them or not.

Among those are:
- persistent handles (corresponding to the share capability CA)
- multi-channel
- leases
- directory leases
- encryption
- large MTU

Of these, samba currently supports leases, encryption, and large MTU. multi-channel support is experimental.
persistent handles are being worked on.

Hope this helps,

Michael
-------------------------------------------------------------------------------------------------------------------------------------
本邮件及其附件含有杭州华三通信技术有限公司的保密信息，仅限于发送给上面地址中列出
的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、
或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本
邮件！
This e-mail and its attachments contain confidential information from H3C, which is
intended only for the person or entity whose address is listed above. Any use of the
information contained herein in any way (including, but not limited to, total or partial
disclosure, reproduction, or dissemination) by persons other than the intended
recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender
by phone or email immediately and delete it!