diff options
Diffstat (limited to 'Documentation/filesystems/nfs')
| -rw-r--r-- | Documentation/filesystems/nfs/fault_injection.txt | 69 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/idmapper.txt | 75 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfs-rdma.txt | 274 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfs.txt | 136 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfsd-admin-interfaces.txt | 41 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfsroot.txt | 355 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/pnfs-block-server.txt | 37 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/pnfs-scsi-server.txt | 23 |
8 files changed, 0 insertions, 1010 deletions
diff --git a/Documentation/filesystems/nfs/fault_injection.txt b/Documentation/filesystems/nfs/fault_injection.txt deleted file mode 100644 index f3a5b0a8ac05..000000000000 --- a/Documentation/filesystems/nfs/fault_injection.txt +++ /dev/null @@ -1,69 +0,0 @@ - -Fault Injection -=============== -Fault injection is a method for forcing errors that may not normally occur, or -may be difficult to reproduce. Forcing these errors in a controlled environment -can help the developer find and fix bugs before their code is shipped in a -production system. Injecting an error on the Linux NFS server will allow us to -observe how the client reacts and if it manages to recover its state correctly. - -NFSD_FAULT_INJECTION must be selected when configuring the kernel to use this -feature. - - -Using Fault Injection -===================== -On the client, mount the fault injection server through NFS v4.0+ and do some -work over NFS (open files, take locks, ...). - -On the server, mount the debugfs filesystem to <debug_dir> and ls -<debug_dir>/nfsd. This will show a list of files that will be used for -injecting faults on the NFS server. As root, write a number n to the file -corresponding to the action you want the server to take. The server will then -process the first n items it finds. So if you want to forget 5 locks, echo '5' -to <debug_dir>/nfsd/forget_locks. A value of 0 will tell the server to forget -all corresponding items. A log message will be created containing the number -of items forgotten (check dmesg). - -Go back to work on the client and check if the client recovered from the error -correctly. - - -Available Faults -================ -forget_clients: - The NFS server keeps a list of clients that have placed a mount call. If - this list is cleared, the server will have no knowledge of who the client - is, forcing the client to reauthenticate with the server. - -forget_openowners: - The NFS server keeps a list of what files are currently opened and who - they were opened by. Clearing this list will force the client to reopen - its files. - -forget_locks: - The NFS server keeps a list of what files are currently locked in the VFS. - Clearing this list will force the client to reclaim its locks (files are - unlocked through the VFS as they are cleared from this list). - -forget_delegations: - A delegation is used to assure the client that a file, or part of a file, - has not changed since the delegation was awarded. Clearing this list will - force the client to reacquire its delegation before accessing the file - again. - -recall_delegations: - Delegations can be recalled by the server when another client attempts to - access a file. This test will notify the client that its delegation has - been revoked, forcing the client to reacquire the delegation before using - the file again. - - -tools/nfs/inject_faults.sh script -================================= -This script has been created to ease the fault injection process. This script -will detect the mounted debugfs directory and write to the files located there -based on the arguments passed by the user. For example, running -`inject_faults.sh forget_locks 1` as root will instruct the server to forget -one lock. Running `inject_faults forget_locks` will instruct the server to -forgetall locks. diff --git a/Documentation/filesystems/nfs/idmapper.txt b/Documentation/filesystems/nfs/idmapper.txt deleted file mode 100644 index b86831acd583..000000000000 --- a/Documentation/filesystems/nfs/idmapper.txt +++ /dev/null @@ -1,75 +0,0 @@ - -========= -ID Mapper -========= -Id mapper is used by NFS to translate user and group ids into names, and to -translate user and group names into ids. Part of this translation involves -performing an upcall to userspace to request the information. There are two -ways NFS could obtain this information: placing a call to /sbin/request-key -or by placing a call to the rpc.idmap daemon. - -NFS will attempt to call /sbin/request-key first. If this succeeds, the -result will be cached using the generic request-key cache. This call should -only fail if /etc/request-key.conf is not configured for the id_resolver key -type, see the "Configuring" section below if you wish to use the request-key -method. - -If the call to /sbin/request-key fails (if /etc/request-key.conf is not -configured with the id_resolver key type), then the idmapper will ask the -legacy rpc.idmap daemon for the id mapping. This result will be stored -in a custom NFS idmap cache. - - -=========== -Configuring -=========== -The file /etc/request-key.conf will need to be modified so /sbin/request-key can -direct the upcall. The following line should be added: - -#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ... -#====== ======= =============== =============== =============================== -create id_resolver * * /usr/sbin/nfs.idmap %k %d 600 - -This will direct all id_resolver requests to the program /usr/sbin/nfs.idmap. -The last parameter, 600, defines how many seconds into the future the key will -expire. This parameter is optional for /usr/sbin/nfs.idmap. When the timeout -is not specified, nfs.idmap will default to 600 seconds. - -id mapper uses for key descriptions: - uid: Find the UID for the given user - gid: Find the GID for the given group - user: Find the user name for the given UID - group: Find the group name for the given GID - -You can handle any of these individually, rather than using the generic upcall -program. If you would like to use your own program for a uid lookup then you -would edit your request-key.conf so it look similar to this: - -#OP TYPE DESCRIPTION CALLOUT INFO PROGRAM ARG1 ARG2 ARG3 ... -#====== ======= =============== =============== =============================== -create id_resolver uid:* * /some/other/program %k %d 600 -create id_resolver * * /usr/sbin/nfs.idmap %k %d 600 - -Notice that the new line was added above the line for the generic program. -request-key will find the first matching line and corresponding program. In -this case, /some/other/program will handle all uid lookups and -/usr/sbin/nfs.idmap will handle gid, user, and group lookups. - -See <file:Documentation/security/keys/request-key.rst> for more information -about the request-key function. - - -========= -nfs.idmap -========= -nfs.idmap is designed to be called by request-key, and should not be run "by -hand". This program takes two arguments, a serialized key and a key -description. The serialized key is first converted into a key_serial_t, and -then passed as an argument to keyctl_instantiate (both are part of keyutils.h). - -The actual lookups are performed by functions found in nfsidmap.h. nfs.idmap -determines the correct function to call by looking at the first part of the -description string. For example, a uid lookup description will appear as -"uid:user@domain". - -nfs.idmap will return 0 if the key was instantiated, and non-zero otherwise. diff --git a/Documentation/filesystems/nfs/nfs-rdma.txt b/Documentation/filesystems/nfs/nfs-rdma.txt deleted file mode 100644 index 22dc0dd6889c..000000000000 --- a/Documentation/filesystems/nfs/nfs-rdma.txt +++ /dev/null @@ -1,274 +0,0 @@ -################################################################################ -# # -# NFS/RDMA README # -# # -################################################################################ - - Author: NetApp and Open Grid Computing - Date: May 29, 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 - - nfs-rdma-devel@lists.sourceforge.net - - 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-1.1.2 or greater on the client - - An NFS/RDMA mount point can be obtained by using the mount.nfs command in - nfs-utils-1.1.2 or greater (nfs-utils-1.1.1 was the first nfs-utils - version with support for NFS/RDMA mounts, but for various reasons we - recommend using nfs-utils-1.1.2 or greater). To see which version of - mount.nfs you are using, type: - - $ /sbin/mount.nfs -V - - If the version is less than 1.1.2 or the command does not exist, - you should 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 need the idmapper and gssd executables (you do not need - these to create an NFS/RDMA enabled mount command), the installation - process can be simplified by disabling these features when running - configure: - - $ ./configure --disable-gss --disable-nfsv4 - - To build nfs-utils you will need the tcp_wrappers package installed. 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. - - This mount.nfs binary should be installed at /sbin/mount.nfs as follows: - - $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs - - In this location, mount.nfs will be invoked automatically for NFS mounts - by the system mount command. - - NOTE: mount.nfs and therefore nfs-utils-1.1.2 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-1.1.2 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 Linux - kernel can be found at: - - https://www.kernel.org/pub/linux/kernel/ - - 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$ ip link set dev ib0 up - host1$ ip address add dev ib0 a.b.c.x - host2$ ip link set dev ib0 up - host2$ ip address add dev 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 formats have been tested: - - /vol0 192.168.0.47(fsid=0,rw,async,insecure,no_root_squash) - /vol0 192.168.0.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash) - - The IP address(es) is(are) the client's IPoIB address for an InfiniBand - HCA or the client's iWARP address(es) for an RNIC. - - NOTE: The "insecure" option must be used because the NFS/RDMA client does - not use a reserved port. - - Each time a machine boots: - - - Load and configure the RDMA drivers - - For InfiniBand using a Mellanox adapter: - - $ modprobe ib_mthca - $ modprobe ib_ipoib - $ ip li set dev ib0 up - $ ip addr add dev 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 20049 > /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), use this - command to mount the NFS/RDMA server: - - $ mount -o rdma,port=20049 <IPoIB-server-name-or-address>:/<export> /mnt - - 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! diff --git a/Documentation/filesystems/nfs/nfs.txt b/Documentation/filesystems/nfs/nfs.txt deleted file mode 100644 index f2571c8bef74..000000000000 --- a/Documentation/filesystems/nfs/nfs.txt +++ /dev/null @@ -1,136 +0,0 @@ - -The NFS client -============== - -The NFS version 2 protocol was first documented in RFC1094 (March 1989). -Since then two more major releases of NFS have been published, with NFSv3 -being documented in RFC1813 (June 1995), and NFSv4 in RFC3530 (April -2003). - -The Linux NFS client currently supports all the above published versions, -and work is in progress on adding support for minor version 1 of the NFSv4 -protocol. - -The purpose of this document is to provide information on some of the -special features of the NFS client that can be configured by system -administrators. - - -The nfs4_unique_id parameter -============================ - -NFSv4 requires clients to identify themselves to servers with a unique -string. File open and lock state shared between one client and one server -is associated with this identity. To support robust NFSv4 state recovery -and transparent state migration, this identity string must not change -across client reboots. - -Without any other intervention, the Linux client uses a string that contains -the local system's node name. System administrators, however, often do not -take care to ensure that node names are fully qualified and do not change -over the lifetime of a client system. Node names can have other -administrative requirements that require particular behavior that does not -work well as part of an nfs_client_id4 string. - -The nfs.nfs4_unique_id boot parameter specifies a unique string that can be -used instead of a system's node name when an NFS client identifies itself to -a server. Thus, if the system's node name is not unique, or it changes, its -nfs.nfs4_unique_id stays the same, preventing collision with other clients -or loss of state during NFS reboot recovery or transparent state migration. - -The nfs.nfs4_unique_id string is typically a UUID, though it can contain -anything that is believed to be unique across all NFS clients. An -nfs4_unique_id string should be chosen when a client system is installed, -just as a system's root file system gets a fresh UUID in its label at -install time. - -The string should remain fixed for the lifetime of the client. It can be -changed safely if care is taken that the client shuts down cleanly and all -outstanding NFSv4 state has expired, to prevent loss of NFSv4 state. - -This string can be stored in an NFS client's grub.conf, or it can be provided -via a net boot facility such as PXE. It may also be specified as an nfs.ko -module parameter. Specifying a uniquifier string is not support for NFS -clients running in containers. - - -The DNS resolver -================ - -NFSv4 allows for one server to refer the NFS client to data that has been -migrated onto another server by means of the special "fs_locations" -attribute. See - http://tools.ietf.org/html/rfc3530#section-6 -and - http://tools.ietf.org/html/draft-ietf-nfsv4-referrals-00 - -The fs_locations information can take the form of either an ip address and -a path, or a DNS hostname and a path. The latter requires the NFS client to -do a DNS lookup in order to mount the new volume, and hence the need for an -upcall to allow userland to provide this service. - -Assuming that the user has the 'rpc_pipefs' filesystem mounted in the usual -/var/lib/nfs/rpc_pipefs, the upcall consists of the following steps: - - (1) The process checks the dns_resolve cache to see if it contains a - valid entry. If so, it returns that entry and exits. - - (2) If no valid entry exists, the helper script '/sbin/nfs_cache_getent' - (may be changed using the 'nfs.cache_getent' kernel boot parameter) - is run, with two arguments: - - the cache name, "dns_resolve" - - the hostname to resolve - - (3) After looking up the corresponding ip address, the helper script - writes the result into the rpc_pipefs pseudo-file - '/var/lib/nfs/rpc_pipefs/cache/dns_resolve/channel' - in the following (text) format: - - "<ip address> <hostname> <ttl>\n" - - Where <ip address> is in the usual IPv4 (123.456.78.90) or IPv6 - (ffee:ddcc:bbaa:9988:7766:5544:3322:1100, ffee::1100, ...) format. - <hostname> is identical to the second argument of the helper - script, and <ttl> is the 'time to live' of this cache entry (in - units of seconds). - - Note: If <ip address> is invalid, say the string "0", then a negative - entry is created, which will cause the kernel to treat the hostname - as having no valid DNS translation. - - - - -A basic sample /sbin/nfs_cache_getent -===================================== - -#!/bin/bash -# -ttl=600 -# -cut=/usr/bin/cut -getent=/usr/bin/getent -rpc_pipefs=/var/lib/nfs/rpc_pipefs -# -die() -{ - echo "Usage: $0 cache_name entry_name" - exit 1 -} - -[ $# -lt 2 ] && die -cachename="$1" -cache_path=${rpc_pipefs}/cache/${cachename}/channel - -case "${cachename}" in - dns_resolve) - name="$2" - result="$(${getent} hosts ${name} | ${cut} -f1 -d\ )" - [ -z "${result}" ] && result="0" - ;; - *) - die - ;; -esac -echo "${result} ${name} ${ttl}" >${cache_path} - diff --git a/Documentation/filesystems/nfs/nfsd-admin-interfaces.txt b/Documentation/filesystems/nfs/nfsd-admin-interfaces.txt deleted file mode 100644 index 56a96fb08a73..000000000000 --- a/Documentation/filesystems/nfs/nfsd-admin-interfaces.txt +++ /dev/null @@ -1,41 +0,0 @@ -Administrative interfaces for nfsd -^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - -Note that normally these interfaces are used only by the utilities in -nfs-utils. - -nfsd is controlled mainly by pseudofiles under the "nfsd" filesystem, -which is normally mounted at /proc/fs/nfsd/. - -The server is always started by the first write of a nonzero value to -nfsd/threads. - -Before doing that, NFSD can be told which sockets to listen on by -writing to nfsd/portlist; that write may be: - - - an ascii-encoded file descriptor, which should refer to a - bound (and listening, for tcp) socket, or - - "transportname port", where transportname is currently either - "udp", "tcp", or "rdma". - -If nfsd is started without doing any of these, then it will create one -udp and one tcp listener at port 2049 (see nfsd_init_socks). - -On startup, nfsd and lockd grace periods start. - -nfsd is shut down by a write of 0 to nfsd/threads. All locks and state -are thrown away at that point. - -Between startup and shutdown, the number of threads may be adjusted up -or down by additional writes to nfsd/threads or by writes to -nfsd/pool_threads. - -For more detail about files under nfsd/ and what they control, see -fs/nfsd/nfsctl.c; most of them have detailed comments. - -Implementation notes -^^^^^^^^^^^^^^^^^^^^ - -Note that the rpc server requires the caller to serialize addition and -removal of listening sockets, and startup and shutdown of the server. -For nfsd this is done using nfsd_mutex. diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt deleted file mode 100644 index ae4332464560..000000000000 --- a/Documentation/filesystems/nfs/nfsroot.txt +++ /dev/null @@ -1,355 +0,0 @@ -Mounting the root filesystem via NFS (nfsroot) -=============================================== - -Written 1996 by Gero Kuhlmann <gero@gkminix.han.de> -Updated 1997 by Martin Mares <mj@atrey.karlin.mff.cuni.cz> -Updated 2006 by Nico Schottelius <nico-kernel-nfsroot@schottelius.org> -Updated 2006 by Horms <horms@verge.net.au> -Updated 2018 by Chris Novakovic <chris@chrisn.me.uk> - - - -In order to use a diskless system, such as an X-terminal or printer server -for example, it is necessary for the root filesystem to be present on a -non-disk device. This may be an initramfs (see Documentation/filesystems/ -ramfs-rootfs-initramfs.txt), a ramdisk (see Documentation/admin-guide/initrd.rst) or a -filesystem mounted via NFS. The following text describes on how to use NFS -for the root filesystem. For the rest of this text 'client' means the -diskless system, and 'server' means the NFS server. - - - - -1.) Enabling nfsroot capabilities - ----------------------------- - -In order to use nfsroot, NFS client support needs to be selected as -built-in during configuration. Once this has been selected, the nfsroot -option will become available, which should also be selected. - -In the networking options, kernel level autoconfiguration can be selected, -along with the types of autoconfiguration to support. Selecting all of -DHCP, BOOTP and RARP is safe. - - - - -2.) Kernel command line - ------------------- - -When the kernel has been loaded by a boot loader (see below) it needs to be -told what root fs device to use. And in the case of nfsroot, where to find -both the server and the name of the directory on the server to mount as root. -This can be established using the following kernel command line parameters: - - -root=/dev/nfs - - This is necessary to enable the pseudo-NFS-device. Note that it's not a - real device but just a synonym to tell the kernel to use NFS instead of - a real device. - - -nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>] - - If the `nfsroot' parameter is NOT given on the command line, - the default "/tftpboot/%s" will be used. - - <server-ip> Specifies the IP address of the NFS server. - The default address is determined by the `ip' parameter - (see below). This parameter allows the use of different - servers for IP autoconfiguration and NFS. - - <root-dir> Name of the directory on the server to mount as root. - If there is a "%s" token in the string, it will be - replaced by the ASCII-representation of the client's - IP address. - - <nfs-options> Standard NFS options. All options are separated by commas. - The following defaults are used: - port = as given by server portmap daemon - rsize = 4096 - wsize = 4096 - timeo = 7 - retrans = 3 - acregmin = 3 - acregmax = 60 - acdirmin = 30 - acdirmax = 60 - flags = hard, nointr, noposix, cto, ac - - -ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>: - <dns0-ip>:<dns1-ip>:<ntp0-ip> - - This parameter tells the kernel how to configure IP addresses of devices - and also how to set up the IP routing table. It was originally called - `nfsaddrs', but now the boot-time IP configuration works independently of - NFS, so it was renamed to `ip' and the old name remained as an alias for - compatibility reasons. - - If this parameter is missing from the kernel command line, all fields are - assumed to be empty, and the defaults mentioned below apply. In general - this means that the kernel tries to configure everything using - autoconfiguration. - - The <autoconf> parameter can appear alone as the value to the `ip' - parameter (without all the ':' characters before). If the value is - "ip=off" or "ip=none", no autoconfiguration will take place, otherwise - autoconfiguration will take place. The most common way to use this - is "ip=dhcp". - - <client-ip> IP address of the client. - - Default: Determined using autoconfiguration. - - <server-ip> IP address of the NFS server. If RARP is used to determine - the client address and this parameter is NOT empty only - replies from the specified server are accepted. - - Only required for NFS root. That is autoconfiguration - will not be triggered if it is missing and NFS root is not - in operation. - - Value is exported to /proc/net/pnp with the prefix "bootserver " - (see below). - - Default: Determined using autoconfiguration. - The address of the autoconfiguration server is used. - - <gw-ip> IP address of a gateway if the server is on a different subnet. - - Default: Determined using autoconfiguration. - - <netmask> Netmask for local network interface. If unspecified - the netmask is derived from the client IP address assuming - classful addressing. - - Default: Determined using autoconfiguration. - - <hostname> Name of the client. If a '.' character is present, anything - before the first '.' is used as the client's hostname, and anything - after it is used as its NIS domain name. May be supplied by - autoconfiguration, but its absence will not trigger autoconfiguration. - If specified and DHCP is used, the user-provided hostname (and NIS - domain name, if present) will be carried in the DHCP request; this - may cause a DNS record to be created or updated for the client. - - Default: Client IP address is used in ASCII notation. - - <device> Name of network device to use. - - Default: If the host only has one device, it is used. - Otherwise the device is determined using - autoconfiguration. This is done by sending - autoconfiguration requests out of all devices, - and using the device that received the first reply. - - <autoconf> Method to use for autoconfiguration. In the case of options - which specify multiple autoconfiguration protocols, - requests are sent using all protocols, and the first one - to reply is used. - - Only autoconfiguration protocols that have been compiled - into the kernel will be used, regardless of the value of - this option. - - off or none: don't use autoconfiguration - (do static IP assignment instead) - on or any: use any protocol available in the kernel - (default) - dhcp: use DHCP - bootp: use BOOTP - rarp: use RARP - both: use both BOOTP and RARP but not DHCP - (old option kept for backwards compatibility) - - if dhcp is used, the client identifier can be used by following - format "ip=dhcp,client-id-type,client-id-value" - - Default: any - - <dns0-ip> IP address of primary nameserver. - Value is exported to /proc/net/pnp with the prefix "nameserver " - (see below). - - Default: None if not using autoconfiguration; determined - automatically if using autoconfiguration. - - <dns1-ip> IP address of secondary nameserver. - See <dns0-ip>. - - <ntp0-ip> IP address of a Network Time Protocol (NTP) server. - Value is exported to /proc/net/ipconfig/ntp_servers, but is - otherwise unused (see below). - - Default: None if not using autoconfiguration; determined - automatically if using autoconfiguration. - - After configuration (whether manual or automatic) is complete, two files - are created in the following format; lines are omitted if their respective - value is empty following configuration: - - - /proc/net/pnp: - - #PROTO: <DHCP|BOOTP|RARP|MANUAL> (depending on configuration method) - domain <dns-domain> (if autoconfigured, the DNS domain) - nameserver <dns0-ip> (primary name server IP) - nameserver <dns1-ip> (secondary name server IP) - nameserver <dns2-ip> (tertiary name server IP) - bootserver <server-ip> (NFS server IP) - - - /proc/net/ipconfig/ntp_servers: - - <ntp0-ip> (NTP server IP) - <ntp1-ip> (NTP server IP) - <ntp2-ip> (NTP server IP) - - <dns-domain> and <dns2-ip> (in /proc/net/pnp) and <ntp1-ip> and <ntp2-ip> - (in /proc/net/ipconfig/ntp_servers) are requested during autoconfiguration; - they cannot be specified as part of the "ip=" kernel command line parameter. - - Because the "domain" and "nameserver" options are recognised by DNS - resolvers, /etc/resolv.conf is often linked to /proc/net/pnp on systems - that use an NFS root filesystem. - - Note that the kernel will not synchronise the system time with any NTP - servers it discovers; this is the responsibility of a user space process - (e.g. an initrd/initramfs script that passes the IP addresses listed in - /proc/net/ipconfig/ntp_servers to an NTP client before mounting the real - root filesystem if it is on NFS). - - -nfsrootdebug - - This parameter enables debugging messages to appear in the kernel - log at boot time so that administrators can verify that the correct - NFS mount options, server address, and root path are passed to the - NFS client. - - -rdinit=<executable file> - - To specify which file contains the program that starts system - initialization, administrators can use this command line parameter. - The default value of this parameter is "/init". If the specified - file exists and the kernel can execute it, root filesystem related - kernel command line parameters, including `nfsroot=', are ignored. - - A description of the process of mounting the root file system can be - found in: - - Documentation/driver-api/early-userspace/early_userspace_support.rst - - - - -3.) Boot Loader - ---------- - -To get the kernel into memory different approaches can be used. -They depend on various facilities being available: - - -3.1) Booting from a floppy using syslinux - - When building kernels, an easy way to create a boot floppy that uses - syslinux is to use the zdisk or bzdisk make targets which use zimage - and bzimage images respectively. Both targets accept the - FDARGS parameter which can be used to set the kernel command line. - - e.g. - make bzdisk FDARGS="root=/dev/nfs" - - Note that the user running this command will need to have - access to the floppy drive device, /dev/fd0 - - For more information on syslinux, including how to create bootdisks - for prebuilt kernels, see http://syslinux.zytor.com/ - - N.B: Previously it was possible to write a kernel directly to - a floppy using dd, configure the boot device using rdev, and - boot using the resulting floppy. Linux no longer supports this - method of booting. - -3.2) Booting from a cdrom using isolinux - - When building kernels, an easy way to create a bootable cdrom that - uses isolinux is to use the isoimage target which uses a bzimage - image. Like zdisk and bzdisk, this target accepts the FDARGS - parameter which can be used to set the kernel command line. - - e.g. - make isoimage FDARGS="root=/dev/nfs" - - The resulting iso image will be arch/<ARCH>/boot/image.iso - This can be written to a cdrom using a variety of tools including - cdrecord. - - e.g. - cdrecord dev=ATAPI:1,0,0 arch/x86/boot/image.iso - - For more information on isolinux, including how to create bootdisks - for prebuilt kernels, see http://syslinux.zytor.com/ - -3.2) Using LILO - When using LILO all the necessary command line parameters may be - specified using the 'append=' directive in the LILO configuration - file. - - However, to use the 'root=' directive you also need to create - a dummy root device, which may be removed after LILO is run. - - mknod /dev/boot255 c 0 255 - - For information on configuring LILO, please refer to its documentation. - -3.3) Using GRUB - When using GRUB, kernel parameter are simply appended after the kernel - specification: kernel <kernel> <parameters> - -3.4) Using loadlin - loadlin may be used to boot Linux from a DOS command prompt without - requiring a local hard disk to mount as root. This has not been - thoroughly tested by the authors of this document, but in general - it should be possible configure the kernel command line similarly - to the configuration of LILO. - - Please refer to the loadlin documentation for further information. - -3.5) Using a boot ROM - This is probably the most elegant way of booting a diskless client. - With a boot ROM the kernel is loaded using the TFTP protocol. The - authors of this document are not aware of any no commercial boot - ROMs that support booting Linux over the network. However, there - are two free implementations of a boot ROM, netboot-nfs and - etherboot, both of which are available on sunsite.unc.edu, and both - of which contain everything you need to boot a diskless Linux client. - -3.6) Using pxelinux - Pxelinux may be used to boot linux using the PXE boot loader - which is present on many modern network cards. - - When using pxelinux, the kernel image is specified using - "kernel <relative-path-below /tftpboot>". The nfsroot parameters - are passed to the kernel by adding them to the "append" line. - It is common to use serial console in conjunction with pxeliunx, - see Documentation/admin-guide/serial-console.rst for more information. - - For more information on isolinux, including how to create bootdisks - for prebuilt kernels, see http://syslinux.zytor.com/ - - - - -4.) Credits - ------- - - The nfsroot code in the kernel and the RARP support have been written - by Gero Kuhlmann <gero@gkminix.han.de>. - - The rest of the IP layer autoconfiguration code has been written - by Martin Mares <mj@atrey.karlin.mff.cuni.cz>. - - In order to write the initial version of nfsroot I would like to thank - Jens-Uwe Mager <jum@anubis.han.de> for his help. diff --git a/Documentation/filesystems/nfs/pnfs-block-server.txt b/Documentation/filesystems/nfs/pnfs-block-server.txt deleted file mode 100644 index 2143673cf154..000000000000 --- a/Documentation/filesystems/nfs/pnfs-block-server.txt +++ /dev/null @@ -1,37 +0,0 @@ -pNFS block layout server user guide - -The Linux NFS server now supports the pNFS block layout extension. In this -case the NFS server acts as Metadata Server (MDS) for pNFS, which in addition -to handling all the metadata access to the NFS export also hands out layouts -to the clients to directly access the underlying block devices that are -shared with the client. - -To use pNFS block layouts with with the Linux NFS server the exported file -system needs to support the pNFS block layouts (currently just XFS), and the -file system must sit on shared storage (typically iSCSI) that is accessible -to the clients in addition to the MDS. As of now the file system needs to -sit directly on the exported volume, striping or concatenation of -volumes on the MDS and clients is not supported yet. - -On the server, pNFS block volume support is automatically if the file system -support it. On the client make sure the kernel has the CONFIG_PNFS_BLOCK -option enabled, the blkmapd daemon from nfs-utils is running, and the -file system is mounted using the NFSv4.1 protocol version (mount -o vers=4.1). - -If the nfsd server needs to fence a non-responding client it calls -/sbin/nfsd-recall-failed with the first argument set to the IP address of -the client, and the second argument set to the device node without the /dev -prefix for the file system to be fenced. Below is an example file that shows -how to translate the device into a serial number from SCSI EVPD 0x80: - -cat > /sbin/nfsd-recall-failed << EOF -#!/bin/sh - -CLIENT="$1" -DEV="/dev/$2" -EVPD=`sg_inq --page=0x80 ${DEV} | \ - grep "Unit serial number:" | \ - awk -F ': ' '{print $2}'` - -echo "fencing client ${CLIENT} serial ${EVPD}" >> /var/log/pnfsd-fence.log -EOF diff --git a/Documentation/filesystems/nfs/pnfs-scsi-server.txt b/Documentation/filesystems/nfs/pnfs-scsi-server.txt deleted file mode 100644 index 5bef7268bd9f..000000000000 --- a/Documentation/filesystems/nfs/pnfs-scsi-server.txt +++ /dev/null @@ -1,23 +0,0 @@ - -pNFS SCSI layout server user guide -================================== - -This document describes support for pNFS SCSI layouts in the Linux NFS server. -With pNFS SCSI layouts, the NFS server acts as Metadata Server (MDS) for pNFS, -which in addition to handling all the metadata access to the NFS export, -also hands out layouts to the clients so that they can directly access the -underlying SCSI LUNs that are shared with the client. - -To use pNFS SCSI layouts with with the Linux NFS server, the exported file -system needs to support the pNFS SCSI layouts (currently just XFS), and the -file system must sit on a SCSI LUN that is accessible to the clients in -addition to the MDS. As of now the file system needs to sit directly on the -exported LUN, striping or concatenation of LUNs on the MDS and clients -is not supported yet. - -On a server built with CONFIG_NFSD_SCSI, the pNFS SCSI volume support is -automatically enabled if the file system is exported using the "pnfs" -option and the underlying SCSI device support persistent reservations. -On the client make sure the kernel has the CONFIG_PNFS_BLOCK option -enabled, and the file system is mounted using the NFSv4.1 protocol -version (mount -o vers=4.1). |