Red Hat Bugzilla – Bug 1452461
NFSv2 is supported at RHEL 7 nfs server end after making changes in /etc/sysconfig/nfs to RPCNFSDARGS="-V 2". Not supported @ RHEL 7 client end.
Last modified: 2018-04-10 14:22:28 EDT
Description of problem: NFSv2 is supported at RHEL7 nfs server end after making changes in /etc/sysconfig/nfs to RPCNFSDARGS="-V 2". Not supported @ RHEL 7 client end. Version-Release number of selected component (if applicable): NFS Server: RHEL 7 NFS Client: RHEL 7 NFS Client: RHEL 6.5 How reproducible: RHEL 7.3 NFS Server: # cat /etc/redhat-release Red Hat Enterprise Linux Workstation release 7.3 (Maipo) # exportfs -rav exporting *:/test1 # grep -i RPCNFSDARGS /etc/sysconfig/nfs RPCNFSDARGS="-V 2" [2] Restartthe nfs-config.service: # systemctl restart nfs-config.service [3] Restart the nfs-server.service # systemctl restart nfs-server.service # rpcinfo -l localhost 100003 2 program vers tp_family/name/class address service 100003 2 inet6/tcp/cots_ord ::1.8.1 nfs 100003 2 inet6/udp/clts ::1.8.1 nfs # systemctl restart nfs-server.service # rpcinfo -p | grep -w nfs 100003 2 tcp 2049 nfs 100003 3 tcp 2049 nfs 100003 4 tcp 2049 nfs 100003 2 udp 2049 nfs 100003 3 udp 2049 nfs 100003 4 udp 2049 nfs NFS Client: RHEL 7.2 # cat /etc/redhat-release Red Hat Enterprise Linux Server release 7.2 (Maipo) # mount -t nfs -o,vers=2 10.76.1.221:/test1 /mnt mount.nfs: Protocol not supported <-----not supported RHEL 6.5: mount operation is successful. # cat /etc/redhat-release Red Hat Enterprise Linux Server release 6.5 (Santiago) # mount -t nfs -o,vers=2 x.x.x.x:/test1 /mnt # grep -i vers=2 /proc/mounts x.x.x.x:/test1 /mnt nfs rw,relatime,vers=2,rsize=8192,wsize=8192,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=x.x.x.x,mountvers=1,mountport=20048,mountproto=udp,local_lock=none,addr=x.x.x.x 0 0 Please make the required changes in man page of nfs along with the RHEL 7 documentation: https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Storage_Administration_Guide/ch-nfs.html
Proposed upstream man page patch: http://lkml.kernel.org/r/20171011160243.GG25913@fieldses.org
Needed upstream commmit commit 25b8f8b9691f10651d900f1ee17f8606853ec544 Author: J. Bruce Fields <bfields@redhat.com> Date: Thu Oct 12 10:18:31 2017 -0400 exports(5): minor exports man page typo commit dcb5b1a7aba7c54c796cd892f2f9071b63ee80e1 Author: J. Bruce Fields <bfields@redhat.com> Date: Thu Oct 12 10:12:58 2017 -0400 nfs(5): update some version information
(In reply to Steve Dickson from comment #8) Verified above 2 commits have been merged now. [root@ ~]# rpm -q nfs-utils nfs-utils-1.3.0-0.52.el7.x86_64 [root@ ~]# [root@ ~]# man exports | col -b | grep "the pNFS extension" pnfs This option enables the use of the pNFS extension if the protocol level is NFSv4.1 or higher, and the filesystem supports pNFS exports. [root@ ~]# [root@ ~]# man nfs | col -b | grep -C 1 "Depending on kernel configuration" NFS is an Internet Standard protocol created by Sun Microsystems in 1984. NFS was developed to allow file sharing between systems residing on a local area network. Depending on kernel configuration, the Linux NFS client may support NFS versions 2, 3, 4.0, 4.1, or 4.2. [root@ ~]# man nfs | col -b | grep -C 1 "the client tries version" nfsvers=n The NFS protocol version number used to contact the server's NFS service. If the server does not support the requested version, the mount request fails. If this option is not specified, the client tries version 4.2 first, then negotiates down until it finds a version supported by the server. [root@ ~]# man nfs | col -b | grep -C 1 "for NFS version 4.0 and newer" Options for NFS version 4 only Use these options, along with the options in the first subsection above, for NFS version 4.0 and newer. [root@ ~]# man nfs | col -b | grep -C 1 "client-established" NFS protocol versions 4.1 and 4.2 use the client-established TCP connection for callback requests, so do not require the server to connect to the client. This option is therefore only affect NFS version 4.0 mounts. [root@ ~]# man nfs | col -b | grep -C 1 "CONFIG_NFS_V2" The Linux client's support for protocol versions depend on whether the kernel was built with options CONFIG_NFS_V2, CONFIG_NFS_V3, CONFIG_NFS_V4, CONFIG_NFS_V4_1, and CONFIG_NFS_V4_2. [root@ ~]# man nfs | col -b | grep -C 1 "version 4.0" Options for NFS version 4 only Use these options, along with the options in the first subsection above, for NFS version 4.0 and newer. -- Specifies a single IPv4 address (in dotted-quad form), or a non-link-local IPv6 address, that the NFS client advertises to allow servers to perform NFS version 4.0 callback requests against files on this mount point. If the server is unable to establish callback connections to clients, performance may degrade, or accesses to files may temporarily hang. -- NFS protocol versions 4.1 and 4.2 use the client-established TCP connection for callback requests, so do not require the server to connect to the client. This option is therefore only affect NFS version 4.0 mounts. -- RFC 2203 for the RPCSEC GSS API protocol specification. RFC 7530 for the NFS version 4.0 specification. RFC 5661 for the NFS version 4.1 specification. [root@ ~]#
Moving to VERIFIED according to comment #21 (plus following log) [root@~ ]# rpm -q nfs-utils nfs-utils-1.3.0-0.53.el7.x86_64 [root@~ ]# man nfs | col -b | grep -A2 nfsvers=n nfsvers=n The NFS protocol version number used to contact the server's NFS service. If the server does not support the requested version, the mount request fails. If this option is not specified, the client tries version 4.1 first, then negotiates down until it finds a ver‐ sion supported by the server. [root@ibm-x3550m4-02 ~]#
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2018:0981