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cifs.smb2 - enable for Windows 2008 R2?

Hello,

I have a customer that is running only Windows 2008 R2 VMs on vSphere 4.1, and is connecting to CIFS share on Netapp FAS 3040. I see that in oiptions this option: cifs.smb2.enable is set to off (so disabled). This customer requires best performance, so I would like to ask if i can enable this option to increase performance from CIFS? Is there anything else I could do to improve/optimize CIFS performance for this customer?

Thanks in advance for your tips...

Re: cifs.smb2 - enable for Windows 2008 R2?

not sure if enabling smb2 will have a performance impact (either + or -), but IMHO for windows 2008 and 7 enabling it will either way be a good thing.

Mark

Re: cifs.smb2 - enable for Windows 2008 R2?

ok, and then clients compatible with smb2 (w7,2008r2 etc) will automatically use smb2? (even when both smb and smb2 are enabled)?

does Windows need any change inside to work with SMB2 or does it just work by default when SMB2 will be enabled?

Re: cifs.smb2 - enable for Windows 2008 R2?

https://now.netapp.com/NOW/knowledge/docs/ontap/rel801/html/ontap/cmdref/man1/na_options.1.htm

cifs.smb2.enable
This option enables SMB 2.0 support on the Filer. When this option is enabled, the Filer uses SMB 2.0 with a Windows client, if the client supports SMB 2.0. When this option is disabled, the Filer will not accept any new SMB 2.0 sessions; existing sessions are not terminated.

Default: off

Effective: Immediately

Persistence: Remains in effect across system reboots

& from http://www.petri.co.il/how-to-disable-smb-2-on-windows-vista-or-server-2008.htm :

"If both the client and server support SMB 2.0, then SMB 2.0 is selected  during the initial negotiation. However, if they don't both support it,  SMB 1.0 will be used to in order to preserve backwards compatibility."

Re: cifs.smb2 - enable for Windows 2008 R2?

m.lubinski a écrit:

[...] Is there anything else I could do to improve/optimize CIFS performance for this customer?

Thanks in advance for your tips...

You may also consider configuring multi mode vif(s) on the controller side with IP+port hashing as load balancing algorithm...

Re: cifs.smb2 - enable for Windows 2008 R2?

Have you tried looking into cifs window size on filer, as default window

size is very small and increasing it would give increase performance.

Re: cifs.smb2 - enable for Windows 2008 R2?

what option is that? I don't see it in options field for CIFS

Re: cifs.smb2 - enable for Windows 2008 R2?

Don't remember now but try with "options cifs" and you should get an option

where you will find default window size set as ~32k .

Will tell you the exact option once I have access to my system.

-Sent from my handheld

Re: cifs.smb2 - enable for Windows 2008 R2?

i know there is default windows size for NFS, but don't see it for CIFS... pls check on your setup, and let me know...

Re: cifs.smb2 - enable for Windows 2008 R2?

Use below option.

"options cifs.tcp_window_size 64240"

You can also try with enabling oplocks, I have tried to add some information

on it below.

BTW have you tried looking at volume settings to increase performance, like

minra, at time update or settings on client side.

cifs.oplocks.enable:

Oplocks (opportunistic locks) enable a CIFS client in certain file-sharing

scenarios to perform client-side caching of read-ahead, write-behind, and

lock information. A client can then read from or write to a file without

regularly reminding the server that it needs access to the file in question.

This improves performance by reducing network traffic. CIFS oplocks on the

filer are on. By default: You might turn CIFS oplocks off under the

following circumstances otherwise, you can leave CIFS oplocks on.

1. You are using a database application whose documentation recommends that

oplocks be turned off.

2. The CIFS clients are on an unreliable network.

3. You are handling critical data and you cannot afford even the slightest

data loss.

-Sent from my handheld