Re: questions about blocklayoutdriver

["白松林" <09120171@xxxxxxxxxxx>]

Hi

In the webpage(http://wiki.linuxnfs.org/wiki/index.php/PNFS_Block_Server_Setup_Instructions),
there is one sentence, mount -t nfs4 -o minorversion=1 SN:/ /mnt/ob 
In this sentence,whether the SN means a MDS or means a DS?


We set up the pNFS environment as follows:
DS:10.27.140.40
MDS:10.27.140.35
Client:10.27.140.38

On DS: 1. the disk was partitioned with "parted",and produced sda6 for client.
       2. added line in /etc/exports as follows
          /pnfs  *(rw,sync,fsid=0,insecure,no_subtree_check,no_root_squash,pnfs)
       3. used the following script to start the DS server 

           #/bin/bash 
           umount /pnfs
           service tgtd restart
           sleep 8
           tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.1992-05.com.emc:openblock
           tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 --backing-store /dev/sda6
           tgtadm --lld iscsi --mode target --op bind --tid 1 --initiator-address ALL
           tgtadm --lld iscsi --op show --mode target
           mount /dev/sda6 /pnfs
           sleep 3
           service nfs restart
           sleep 3
           cd
/ctl/
           ./ctl -u &
On MDS: 1. added line in /etc/exports
           / *(rw,fsid=0,insecure,no_root_squash,sync,no_subtree_check,pnfs)
        2. created the folder
           mkdir /spnfs/10.27.140.40
        3. mount 10.27.140.40:/pnfs /spnfs/10.27.140.40
        4. run spnfsd and the content of /etc/spnfs.conf as follows
            
           [General]
           Verbosity = 1
           Stripe-size = 8192
           Dense-striping = 0
           Pipefs-Directory = /var/lib/nfs/rpc_pipefs
           DS-Mount-Directory = /spnfs
 
           [DataServers]
           NumDS = 1
           DS1_IP = 10.27.140.40
           DS1_PORT = 2049
           DS1_ROOT = /pnfs
           DS1_ID = 1

On client: 1.  connectted to iscsi targets
               iscsiadm -m discovery -t sendtargets -p 10.27.140.40 -l
           2.  start the block layout service
               initd.redhat restart
           3.  mounted the MDS　server
　　　　　　　 mount -t nfs4 -o minorversion=1 10.27.140.35:/spnfs  /mnt

We tested the pNFS informance in the environment,and found that when client write data to client:/mnt,
all of the data be sent to MDS firstly, and then MDS forwarded the data to DS,when we got the 
package by wireshark,and found most of the protocol between MDS and DS are NFS and TCP.

I don't konw why the data be sent to MDS firstly, and I think it should be sent to DS from 
client dircetly with iSCSI protocol.
Can you point where is the error?

Thanks.
Songlin BAI. 






>From: Jim Rees

>Reply-To: 
>To: 白松林

>Subject: Re: questions about blocklayoutdriver
>Date: Tue, 1 Mar 2011 09:17:50 -0500
>
>白松林 wrote:
>
>  I am a postgraduate at BeiJing JiaoTong university in china. In our
>  lab,including our professor,we are interested in PNFS.  Now,we have been
>  set up the test environment with the nfs_layout_nfsv41_files.ko, and it
>  can run successfully.  But,we do not konw how to use blocklayoutdirver.ko.
>  Can you tell me something about how to use it?
>
>You can find some documentation here:
>http://wiki.linux-nfs.org/wiki/index.php/Fedora_pNFS_Client_Setup
>
>If you have specific questions I will be happy to answer them.
> ?韬{.n?????%??檩??w?{.n???{炳w忐)?骅w*jg????????G??⒏⒎?:+v????????????＂??????