From 5e12f172db9536df4720a50e8aa70c5e212c2037 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 21 Mar 2022 16:20:43 +1100 Subject: [PATCH] NFS: update documentation for the nfs4_unique_id parameter The documentation for nfs4_unique_id is out-of-date.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 Signed-off-by: Anna Schumaker --- Documentation/admin-guide/nfs/nfs-client.rst | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/Documentation/admin-guide/nfs/nfs-client.rst b/Documentation/admin-guide/nfs/nfs-client.rst index 6adb645..3676068 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 +52,12 @@ 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 unless it is overridden by a value written to +/sys/fs/nfs/net/nfs_client/identifier which will be local to the network +namespace of the process which writes. The DNS resolver -- 2.7.4