OpLocks SMB3.0 Server 2019 Leasing mode (here we go again...)

[pennyman]

thread184-1800416
As an update to the above thread, please note the article referenced by Griff in his post of 20 Jan 20 8:59 is now dead. The article can now be found at: [URL unfurl="true"]https://kb.datafile.co.uk/article.php?id=2132[/url].

Does anyone have any further experience or comment on using Server 2019 with a native VFP database using leasing mode, or otherwise? I'm about to replace an aging server, so would be grateful of any comment. Otherwise I'll document my experience as I go.

Thank you,

Mike.

 

[pennyman]

I note thread184-1809732 refers to this.

 

[Chris Miller]

Right, I welcome this kind of feedback.

To classify the relevance of experiences I'd like to know database sizes and number of concurrent users, etc.
It's not good enough when this works for a small set of users or a small set of data.

The simplest solution to avoid oplocks is by having data local, which is possible by installing EXE and data on a Terminal Server and remote usage (RDP) of the EXE by users. Beccause even shared use of local DBFs by multiple users in parallel doesn't mean use of the DBF files through network. Which means the whole SMB protocol isn't used at all.

This just means other costs for a high performance server and connection/usage licenses. And it's not the same as putting EXXE and ddata on a file share and letting users run that. They still load the EXE to their local client PC And act on the data through the network where SMB problems can kick in. Copying the EXE local then also doesn't mean to avoid networked database access, only TS and RDP do that, with the disadvantage of needing a high performance server.

You can reduce user license costs using Teamviewer or such tools, but you still need much CPU and RAM power to allow multiple users to connect to the same "appliation server". You just can use a universal license of such remote access tools to avoid the license costs MS wants for TS.

Chriss

 

[fitedgar]

yes.
I've read in the past that some are using Synology NAS box for their VFP application.
Would anybody care to elaborate ?


Edgar
Integrated Bar Code Systems, Inc.

 

[pennyman]

Hi Edgar,

Yes I've come across this. I this was a method of providing smb 1 storage for shared VFP data without affecting an entire server by switching off SMB1, or altering client network configuration. I suspect this is now defunct given current Windows 10 clients no longer support smb 1 connections. SMB 3.0 and Leasing mode seems to be the way forward. (ref synology NAS forum SMB1 & W10)

 

[Chris Miller]

From what I've readd the way a NAS helps is by not using MS original SMB protocol as a NAS is Linux based. The implementation of SMB features under Linux seems to be more stable in that aspect. Likely just because it's incomplete.

I also think a NAS solution points out a smaller user base. NAS devices nowadays can be standalone attached to a wrouter/switch not needing a host server, but whenever you access a NAS through a larger network you go through some Windows nodes and the SMB protocol might hit there, too.


The Leasing mode paragraph is very interesting, it suggests you now finally can decide to disallow oplocks for a share and work flawless in that respect. This part of the Note is disconcerting:

...the removal of oplocks and leases causes instability and data corruption in most applications

We know for VFP it's vice versa - OpLocks are the root cause of data corruptions and lag/timing problems, likely because of some not fully documented ways of VFP regarding locks of records, but also how transactions and concurrency are handled.

So I'd go for the -LeasingMode None parameter. And I still agree it would help to know experiences with that.

Chriss

 

[jwilson58]

Re: Synology servers and VFP
We have 15 locations running POS systems. Plus all back-office functions at our main office and distribution center. All running on in-house developed VFP based software and on Synology servers. Everything from FPD2.6 dos legacy stuff up thru VFP 9 current releases. Even running SBT accounting software for AP and GL which is VFP 6.0 based. We have been running on Synology since 2012. We migrated from Novell and have never used a Windows-based server. Never had a problem with Op_Locks. I just turn it off in Synology’s Disk Station Manager and off we go. Synology gives us all the benefits of a modern server without all of the overhead of maintaining a Windows server system.

John

 

[John2R]

Re: Synology servers and VFP
I'm with John, We are running POS systems on clustered Synology NAS. We switched from Windows Server Cluster for hosting VFP databases when pricing got outrageous. Synology has been a dream, Updates and fixes applied real time with no restart, Op_Locks handled in the File Station daemon running on the NAS, and the Synology is the network time source! No collisions or corruptions.

John