nfsd: Update console message for no session found

The NFSv4.1/4.2 server generates a console message that indicates
that there is no session. I was until recently perplexed w.r.t. how
this could occur. It turns out that the common cause is multiple NFS
clients with the same /etc/hostid.

The host uuid is used by the FreeBSD NFSv4.1/4.2 client as a unique
identifier for the client. If multiple clients use the same host uuid,
this indicates to the NFSv4.1/4.2 server that they are the same client
and confusion occurs.

This trivial patch modifies the console message to suggest that the
client's /etc/hostid needs to be checked for uniqueness.

Reviewed by:	asomers
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D36377

1 files changed, 5 insertions, 2 deletions

diff --git a/sys/fs/nfsserver/nfs_nfsdstate.c b/sys/fs/nfsserver/nfs_nfsdstate.c
index aac845e68af7..d5d7f9fbd363 100644
--- a/sys/fs/nfsserver/nfs_nfsdstate.c
+++ b/sys/fs/nfsserver/nfs_nfsdstate.c
@@ -6383,9 +6383,12 @@ nfsrv_cache_session(struct nfsrv_descript *nd, struct mbuf **m)
 			}
 			if (cp != NULL)
 				printf("nfsrv_cache_session: no session "
-				    "IPaddr=%s\n", cp);
+				    "IPaddr=%s, check NFS clients for unique "
+				    "/etc/hostid's\n", cp);
 			else
-				printf("nfsrv_cache_session: no session\n");
+				printf("nfsrv_cache_session: no session, "
+				    "check NFS clients for unique "
+				    "/etc/hostid's\n");
 			free(buf, M_TEMP);
 		}
 		m_freem(*m);