2022-03-21 22:47:46

by NeilBrown

[permalink] [raw]
Subject: [PATCH] NFS: update documentation for the nfs4_unique_id parameter


The documentation for nfs4_unique_id is out-of-date. In particular it
claim that when nfs4_unique_id is set, the host name is not used. since
Commit 55b592933b7d ("NFSv4: Fix nfs4_init_uniform_client_string for net
namespaces") both the unique_id AND the host name are used.

Update the documentation to match the code.

Signed-off-by: NeilBrown <[email protected]>
---
Documentation/admin-guide/nfs/nfs-client.rst | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/Documentation/admin-guide/nfs/nfs-client.rst b/Documentation/admin-guide/nfs/nfs-client.rst
index 6adb6457bc69..c34b8484a9ac 100644
--- a/Documentation/admin-guide/nfs/nfs-client.rst
+++ b/Documentation/admin-guide/nfs/nfs-client.rst
@@ -36,10 +36,9 @@ 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.
+used together with a system's node name when an NFS client identifies itself to
+a server. Thus, if the system's node name is not unique, its
+nfs.nfs4_unique_id can help prevent collisions with other clients.

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
@@ -53,8 +52,9 @@ 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.
+module parameter. This uniquifier string will be the same for all NFS clients
+running in containers. These clients can be given further uniqueness using
+/sys/fs/nfs/net/nfs_client/identifier.


The DNS resolver
--
2.35.1