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authorJ. Bruce Fields <bfields@redhat.com>2020-07-31 03:33:57 +0300
committerJ. Bruce Fields <bfields@redhat.com>2020-09-26 01:01:26 +0300
commite56dc9e2949edff7932474f2552dd134734cc857 (patch)
treee0bafbb7b8a1cba71e0a9a8e250b6fbf77d883f4 /Documentation/admin-guide/nfs
parent856deb866d16e29bd65952e0289066f6078af773 (diff)
downloadlinux-e56dc9e2949edff7932474f2552dd134734cc857.tar.xz
nfsd: remove fault injection code
It was an interesting idea but nobody seems to be using it, it's buggy at this point, and nfs4state.c is already complicated enough without it. The new nfsd/clients/ code provides some of the same functionality, and could probably do more if desired. This feature has been deprecated since 9d60d93198c6 ("Deprecate nfsd fault injection"). Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'Documentation/admin-guide/nfs')
-rw-r--r--Documentation/admin-guide/nfs/fault_injection.rst70
-rw-r--r--Documentation/admin-guide/nfs/index.rst1
2 files changed, 0 insertions, 71 deletions
diff --git a/Documentation/admin-guide/nfs/fault_injection.rst b/Documentation/admin-guide/nfs/fault_injection.rst
deleted file mode 100644
index eb029c0c15ce..000000000000
--- a/Documentation/admin-guide/nfs/fault_injection.rst
+++ /dev/null
@@ -1,70 +0,0 @@
-===================
-NFS 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/admin-guide/nfs/index.rst b/Documentation/admin-guide/nfs/index.rst
index 6b5a3c90fac5..3601a708f333 100644
--- a/Documentation/admin-guide/nfs/index.rst
+++ b/Documentation/admin-guide/nfs/index.rst
@@ -12,4 +12,3 @@ NFS
nfs-idmapper
pnfs-block-server
pnfs-scsi-server
- fault_injection