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To:     linux-nfs@vger.kernel.org
From:   Jianchao Wang <jianchao.wan9@gmail.com>
Subject: Can we setup pNFS with multiple DSs ?
Message-ID: <71d00ed4-78b8-cefb-4245-99f3e53e5d2a@gmail.com>
Date:   Wed, 12 Jun 2019 15:55:07 +0800
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Hi

I'm trying to setup a pNFS experiment environment.
And this is what I have got, 
VM-0 (DS)      running a iscsi target
VM-1 (MS)      initiator, mount a XFS on the device, and export it by NFS with pnfs option
VM-2 (Client)  initiator, but not mount, running a blkmapd
               mount the shared directory of VM-1 by NFS

And it semes to work well as the mountstatus
            LAYOUTGET: 14 14 0 3472 2744 1 1381 1384
	GETDEVICEINFO: 1 1 0 196 148 0 5 5
	 LAYOUTCOMMIT: 8 8 0 2352 1368 0 1256 1257

The kernel version I use is 4.18.19.

And would anyone please help to clarify following questions ?
1. Can I involve multiple DSs here ?
2. Is this stable enough to use in production ? How about earlier version, for example 4.14 ?

Many thanks in advance
Jianchao