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3#				NFS/RDMA README				       #
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6
7 Author: NetApp and Open Grid Computing
8 Date: May 29, 2008
9
10Table of Contents
11~~~~~~~~~~~~~~~~~
12 - Overview
13 - Getting Help
14 - Installation
15 - Check RDMA and NFS Setup
16 - NFS/RDMA Setup
17
18Overview
19~~~~~~~~
20
21  This document describes how to install and setup the Linux NFS/RDMA client
22  and server software.
23
24  The NFS/RDMA client was first included in Linux 2.6.24. The NFS/RDMA server
25  was first included in the following release, Linux 2.6.25.
26
27  In our testing, we have obtained excellent performance results (full 10Gbit
28  wire bandwidth at minimal client CPU) under many workloads. The code passes
29  the full Connectathon test suite and operates over both Infiniband and iWARP
30  RDMA adapters.
31
32Getting Help
33~~~~~~~~~~~~
34
35  If you get stuck, you can ask questions on the
36
37                nfs-rdma-devel@lists.sourceforge.net
38
39  mailing list.
40
41Installation
42~~~~~~~~~~~~
43
44  These instructions are a step by step guide to building a machine for
45  use with NFS/RDMA.
46
47  - Install an RDMA device
48
49    Any device supported by the drivers in drivers/infiniband/hw is acceptable.
50
51    Testing has been performed using several Mellanox-based IB cards, the
52    Ammasso AMS1100 iWARP adapter, and the Chelsio cxgb3 iWARP adapter.
53
54  - Install a Linux distribution and tools
55
56    The first kernel release to contain both the NFS/RDMA client and server was
57    Linux 2.6.25  Therefore, a distribution compatible with this and subsequent
58    Linux kernel release should be installed.
59
60    The procedures described in this document have been tested with
61    distributions from Red Hat's Fedora Project (http://fedora.redhat.com/).
62
63  - Install nfs-utils-1.1.2 or greater on the client
64
65    An NFS/RDMA mount point can be obtained by using the mount.nfs command in
66    nfs-utils-1.1.2 or greater (nfs-utils-1.1.1 was the first nfs-utils
67    version with support for NFS/RDMA mounts, but for various reasons we
68    recommend using nfs-utils-1.1.2 or greater). To see which version of
69    mount.nfs you are using, type:
70
71    $ /sbin/mount.nfs -V
72
73    If the version is less than 1.1.2 or the command does not exist,
74    you should install the latest version of nfs-utils.
75
76    Download the latest package from:
77
78    http://www.kernel.org/pub/linux/utils/nfs
79
80    Uncompress the package and follow the installation instructions.
81
82    If you will not need the idmapper and gssd executables (you do not need
83    these to create an NFS/RDMA enabled mount command), the installation
84    process can be simplified by disabling these features when running
85    configure:
86
87    $ ./configure --disable-gss --disable-nfsv4
88
89    To build nfs-utils you will need the tcp_wrappers package installed. For
90    more information on this see the package's README and INSTALL files.
91
92    After building the nfs-utils package, there will be a mount.nfs binary in
93    the utils/mount directory. This binary can be used to initiate NFS v2, v3,
94    or v4 mounts. To initiate a v4 mount, the binary must be called
95    mount.nfs4.  The standard technique is to create a symlink called
96    mount.nfs4 to mount.nfs.
97
98    This mount.nfs binary should be installed at /sbin/mount.nfs as follows:
99
100    $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs
101
102    In this location, mount.nfs will be invoked automatically for NFS mounts
103    by the system mount command.
104
105    NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed
106    on the NFS client machine. You do not need this specific version of
107    nfs-utils on the server. Furthermore, only the mount.nfs command from
108    nfs-utils-1.1.2 is needed on the client.
109
110  - Install a Linux kernel with NFS/RDMA
111
112    The NFS/RDMA client and server are both included in the mainline Linux
113    kernel version 2.6.25 and later. This and other versions of the 2.6 Linux
114    kernel can be found at:
115
116    ftp://ftp.kernel.org/pub/linux/kernel/v2.6/
117
118    Download the sources and place them in an appropriate location.
119
120  - Configure the RDMA stack
121
122    Make sure your kernel configuration has RDMA support enabled. Under
123    Device Drivers -> InfiniBand support, update the kernel configuration
124    to enable InfiniBand support [NOTE: the option name is misleading. Enabling
125    InfiniBand support is required for all RDMA devices (IB, iWARP, etc.)].
126
127    Enable the appropriate IB HCA support (mlx4, mthca, ehca, ipath, etc.) or
128    iWARP adapter support (amso, cxgb3, etc.).
129
130    If you are using InfiniBand, be sure to enable IP-over-InfiniBand support.
131
132  - Configure the NFS client and server
133
134    Your kernel configuration must also have NFS file system support and/or
135    NFS server support enabled. These and other NFS related configuration
136    options can be found under File Systems -> Network File Systems.
137
138  - Build, install, reboot
139
140    The NFS/RDMA code will be enabled automatically if NFS and RDMA
141    are turned on. The NFS/RDMA client and server are configured via the hidden
142    SUNRPC_XPRT_RDMA config option that depends on SUNRPC and INFINIBAND. The
143    value of SUNRPC_XPRT_RDMA will be:
144
145     - N if either SUNRPC or INFINIBAND are N, in this case the NFS/RDMA client
146       and server will not be built
147     - M if both SUNRPC and INFINIBAND are on (M or Y) and at least one is M,
148       in this case the NFS/RDMA client and server will be built as modules
149     - Y if both SUNRPC and INFINIBAND are Y, in this case the NFS/RDMA client
150       and server will be built into the kernel
151
152    Therefore, if you have followed the steps above and turned no NFS and RDMA,
153    the NFS/RDMA client and server will be built.
154
155    Build a new kernel, install it, boot it.
156
157Check RDMA and NFS Setup
158~~~~~~~~~~~~~~~~~~~~~~~~
159
160    Before configuring the NFS/RDMA software, it is a good idea to test
161    your new kernel to ensure that the kernel is working correctly.
162    In particular, it is a good idea to verify that the RDMA stack
163    is functioning as expected and standard NFS over TCP/IP and/or UDP/IP
164    is working properly.
165
166  - Check RDMA Setup
167
168    If you built the RDMA components as modules, load them at
169    this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel
170    card:
171
172    $ modprobe ib_mthca
173    $ modprobe ib_ipoib
174
175    If you are using InfiniBand, make sure there is a Subnet Manager (SM)
176    running on the network. If your IB switch has an embedded SM, you can
177    use it. Otherwise, you will need to run an SM, such as OpenSM, on one
178    of your end nodes.
179
180    If an SM is running on your network, you should see the following:
181
182    $ cat /sys/class/infiniband/driverX/ports/1/state
183    4: ACTIVE
184
185    where driverX is mthca0, ipath5, ehca3, etc.
186
187    To further test the InfiniBand software stack, use IPoIB (this
188    assumes you have two IB hosts named host1 and host2):
189
190    host1$ ifconfig ib0 a.b.c.x
191    host2$ ifconfig ib0 a.b.c.y
192    host1$ ping a.b.c.y
193    host2$ ping a.b.c.x
194
195    For other device types, follow the appropriate procedures.
196
197  - Check NFS Setup
198
199    For the NFS components enabled above (client and/or server),
200    test their functionality over standard Ethernet using TCP/IP or UDP/IP.
201
202NFS/RDMA Setup
203~~~~~~~~~~~~~~
204
205  We recommend that you use two machines, one to act as the client and
206  one to act as the server.
207
208  One time configuration:
209
210  - On the server system, configure the /etc/exports file and
211    start the NFS/RDMA server.
212
213    Exports entries with the following formats have been tested:
214
215    /vol0   192.168.0.47(fsid=0,rw,async,insecure,no_root_squash)
216    /vol0   192.168.0.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash)
217
218    The IP address(es) is(are) the client's IPoIB address for an InfiniBand
219    HCA or the cleint's iWARP address(es) for an RNIC.
220
221    NOTE: The "insecure" option must be used because the NFS/RDMA client does
222    not use a reserved port.
223
224 Each time a machine boots:
225
226  - Load and configure the RDMA drivers
227
228    For InfiniBand using a Mellanox adapter:
229
230    $ modprobe ib_mthca
231    $ modprobe ib_ipoib
232    $ ifconfig ib0 a.b.c.d
233
234    NOTE: use unique addresses for the client and server
235
236  - Start the NFS server
237
238    If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
239    kernel config), load the RDMA transport module:
240
241    $ modprobe svcrdma
242
243    Regardless of how the server was built (module or built-in), start the
244    server:
245
246    $ /etc/init.d/nfs start
247
248    or
249
250    $ service nfs start
251
252    Instruct the server to listen on the RDMA transport:
253
254    $ echo rdma 20049 > /proc/fs/nfsd/portlist
255
256  - On the client system
257
258    If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in
259    kernel config), load the RDMA client module:
260
261    $ modprobe xprtrdma.ko
262
263    Regardless of how the client was built (module or built-in), use this
264    command to mount the NFS/RDMA server:
265
266    $ mount -o rdma,port=20049 <IPoIB-server-name-or-address>:/<export> /mnt
267
268    To verify that the mount is using RDMA, run "cat /proc/mounts" and check
269    the "proto" field for the given mount.
270
271  Congratulations! You're using NFS/RDMA!
272