On Mon, 25 Feb 2008, Roland Dreier wrote:
> > + - Install an OpenFabrics-compatible RDMA card
> > +
> > + Any device that is compatible with the OpenFabrics.org software stack is
> > + acceptable.
>
> This seems a little odd in the context of instructions on how to use
> the code in the kernel. Maybe something like:
>
> - Install an RDMA device
>
> Any device supported by the drivers in drivers/infiniband/hw is
> acceptable.
>
> - R.
I agree. Your wording is clearer.
Bruce,
Here's an update incorporating Roland's suggestion.
Signed-off-by: James Lentini <[email protected]>
--- /dev/null 2008-01-17 11:34:08.491004516 -0500
+++ Documentation/nfs-rdma.txt 2008-02-25 12:18:17.937932000 -0500
@@ -0,0 +1,252 @@
+################################################################################
+# #
+# NFS/RDMA README #
+# #
+################################################################################
+
+ Author: NetApp and Open Grid Computing
+ Date: February 25, 2008
+
+Table of Contents
+~~~~~~~~~~~~~~~~~
+ - Overview
+ - Getting Help
+ - Installation
+ - Check RDMA and NFS Setup
+ - NFS/RDMA Setup
+
+Overview
+~~~~~~~~
+
+ This document describes how to install and setup the Linux NFS/RDMA client
+ and server software.
+
+ The NFS/RDMA client was first included in Linux 2.6.24. The NFS/RDMA server
+ was first included in the following release, Linux 2.6.25.
+
+ In our testing, we have obtained excellent performance results (full 10Gbit
+ wire bandwidth at minimal client CPU) under many workloads. The code passes
+ the full Connectathon test suite and operates over both Infiniband and iWARP
+ RDMA adapters.
+
+Getting Help
+~~~~~~~~~~~~
+
+ If you get stuck, you can ask questions on the
+
+ [email protected]
+
+ mailing list.
+
+Installation
+~~~~~~~~~~~~
+
+ These instructions are a step by step guide to building a machine for
+ use with NFS/RDMA.
+
+ - Install an RDMA device
+
+ Any device supported by the drivers in drivers/infiniband/hw is acceptable.
+
+ Testing has been performed using several Mellanox-based IB cards, the
+ Ammasso AMS1100 iWARP adapter, and the Chelsio cxgb3 iWARP adapter.
+
+ - Install a Linux distribution and tools
+
+ The first kernel release to contain both the NFS/RDMA client and server was
+ Linux 2.6.25 Therefore, a distribution compatible with this and subsequent
+ Linux kernel release should be installed.
+
+ The procedures described in this document have been tested with
+ distributions from Red Hat's Fedora Project (http://fedora.redhat.com/).
+
+ - Install nfs-utils-1.1.1 or greater on the client
+
+ An NFS/RDMA mount point can only be obtained by using the mount.nfs
+ command in nfs-utils-1.1.1 or greater. To see which version of mount.nfs
+ you are using, type:
+
+ > /sbin/mount.nfs -V
+
+ If the version is less than 1.1.1 or the command does not exist,
+ then you will need to install the latest version of nfs-utils.
+
+ Download the latest package from:
+
+ http://www.kernel.org/pub/linux/utils/nfs
+
+ Uncompress the package and follow the installation instructions.
+
+ If you will not be using GSS and NFSv4, the installation process
+ can be simplified by disabling these features when running configure:
+
+ > ./configure --disable-gss --disable-nfsv4
+
+ For more information on this see the package's README and INSTALL files.
+
+ After building the nfs-utils package, there will be a mount.nfs binary in
+ the utils/mount directory. This binary can be used to initiate NFS v2, v3,
+ or v4 mounts. To initiate a v4 mount, the binary must be called mount.nfs4.
+ The standard technique is to create a symlink called mount.nfs4 to mount.nfs.
+
+ NOTE: mount.nfs and therefore nfs-utils-1.1.1 or greater is only needed
+ on the NFS client machine. You do not need this specific version of
+ nfs-utils on the server. Furthermore, only the mount.nfs command from
+ nfs-utils-1.1.1 is needed on the client.
+
+ - Install a Linux kernel with NFS/RDMA
+
+ The NFS/RDMA client and server are both included in the mainline Linux
+ kernel version 2.6.25 and later. This and other versions of the 2.6 Linux
+ kernel can be found at:
+
+ ftp://ftp.kernel.org/pub/linux/kernel/v2.6/
+
+ Download the sources and place them in an appropriate location.
+
+ - Configure the RDMA stack
+
+ Make sure your kernel configuration has RDMA support enabled. Under
+ Device Drivers -> InfiniBand support, update the kernel configuration
+ to enable InfiniBand support [NOTE: the option name is misleading. Enabling
+ InfiniBand support is required for all RDMA devices (IB, iWARP, etc.)].
+
+ Enable the appropriate IB HCA support (mlx4, mthca, ehca, ipath, etc.) or
+ iWARP adapter support (amso, cxgb3, etc.).
+
+ If you are using InfiniBand, be sure to enable IP-over-InfiniBand support.
+
+ - Configure the NFS client and server
+
+ Your kernel configuration must also have NFS file system support and/or
+ NFS server support enabled. These and other NFS related configuration
+ options can be found under File Systems -> Network File Systems.
+
+ - Build, install, reboot
+
+ The NFS/RDMA code will be enabled automatically if NFS and RDMA
+ are turned on. The NFS/RDMA client and server are configured via the hidden
+ SUNRPC_XPRT_RDMA config option that depends on SUNRPC and INFINIBAND. The
+ value of SUNRPC_XPRT_RDMA will be:
+
+ - N if either SUNRPC or INFINIBAND are N, in this case the NFS/RDMA client
+ and server will not be built
+ - M if both SUNRPC and INFINIBAND are on (M or Y) and at least one is M,
+ in this case the NFS/RDMA client and server will be built as modules
+ - Y if both SUNRPC and INFINIBAND are Y, in this case the NFS/RDMA client
+ and server will be built into the kernel
+
+ Therefore, if you have followed the steps above and turned no NFS and RDMA,
+ the NFS/RDMA client and server will be built.
+
+ Build a new kernel, install it, boot it.
+
+Check RDMA and NFS Setup
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+ Before configuring the NFS/RDMA software, it is a good idea to test
+ your new kernel to ensure that the kernel is working correctly.
+ In particular, it is a good idea to verify that the RDMA stack
+ is functioning as expected and standard NFS over TCP/IP and/or UDP/IP
+ is working properly.
+
+ - Check RDMA Setup
+
+ If you built the RDMA components as modules, load them at
+ this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel
+ card:
+
+ > modprobe ib_mthca
+ > modprobe ib_ipoib
+
+ If you are using InfiniBand, make sure there is a Subnet Manager (SM)
+ running on the network. If your IB switch has an embedded SM, you can
+ use it. Otherwise, you will need to run an SM, such as OpenSM, on one
+ of your end nodes.
+
+ If an SM is running on your network, you should see the following:
+
+ > cat /sys/class/infiniband/driverX/ports/1/state
+ 4: ACTIVE
+
+ where driverX is mthca0, ipath5, ehca3, etc.
+
+ To further test the InfiniBand software stack, use IPoIB (this
+ assumes you have two IB hosts named host1 and host2):
+
+ host1> ifconfig ib0 a.b.c.x
+ host2> ifconfig ib0 a.b.c.y
+ host1> ping a.b.c.y
+ host2> ping a.b.c.x
+
+ For other device types, follow the appropriate procedures.
+
+ - Check NFS Setup
+
+ For the NFS components enabled above (client and/or server),
+ test their functionality over standard Ethernet using TCP/IP or UDP/IP.
+
+NFS/RDMA Setup
+~~~~~~~~~~~~~~
+
+ We recommend that you use two machines, one to act as the client and
+ one to act as the server.
+
+ One time configuration:
+
+ - On the server system, configure the /etc/exports file and
+ start the NFS/RDMA server.
+
+ Exports entries with the following format have been tested:
+
+ /vol0 10.97.103.47(rw,async) 192.168.0.47(rw,async,insecure,no_root_squash)
+
+ Here the first IP address is the client's Ethernet address and the second
+ IP address is the clients IPoIB address.
+
+ Each time a machine boots:
+
+ - Load and configure the RDMA drivers
+
+ For InfiniBand using a Mellanox adapter:
+
+ > modprobe ib_mthca
+ > modprobe ib_ipoib
+ > ifconfig ib0 a.b.c.d
+
+ NOTE: use unique addresses for the client and server
+
+ - Start the NFS server
+
+ If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
+ load the RDMA transport module:
+
+ > modprobe svcrdma
+
+ Regardless of how the server was built (module or built-in), start the server:
+
+ > /etc/init.d/nfs start
+
+ or
+
+ > service nfs start
+
+ Instruct the server to listen on the RDMA transport:
+
+ > echo rdma 2050 > /proc/fs/nfsd/portlist
+
+ - On the client system
+
+ If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
+ load the RDMA client module:
+
+ > modprobe xprtrdma.ko
+
+ Regardless of how the client was built (module or built-in), issue the mount.nfs command:
+
+ > /path/to/your/mount.nfs <IPoIB-server-name-or-address>:/<export> /mnt -i -o rdma,port=2050
+
+ To verify that the mount is using RDMA, run "cat /proc/mounts" and check the
+ "proto" field for the given mount.
+
+ Congratulations! You're using NFS/RDMA!