NFS allows a linux server to share directories with other UNIX clients over network. NFS server exports a directory and NFS client mounts this directory. RHEL 7 supports two version of NFS \u2013 NFSv3 and NFSv4.<\/p>\n
NFS server and RPC processes<\/p>\n
starting the nfs-server process starts the NFS server and other RPC processes. RPC processes includes:
\n\u2013 rpc.statd : implements monitoring protocol (NSM) between NFS client and NFS server
\n\u2013 rpc.mountd : NFS mount daemon that implements the server side of the mount requests from NFSv3 clients.
\n\u2013 rpc.idmapd : Maps NFSv4 names and local UIDs and GIDs
\n\u2013 rpc.rquotad : provides user quota information for remote users.<\/p>\n
Configuring NFS server<\/p>\n
1. Install the required nfs packages if not already installed on the server :<\/p>\n
# rpm -qa | grep nfs-utils
\n# yum install nfs-utils rpcbind
\n2. Enable the services at boot time:<\/p>\n
# systemctl enable nfs-server
\n# systemctl enable rpcbind
\n# systemctl enable nfs-lock
\nIn RHEL7.1 (nfs-utils-1.3.0-8.el7) enabling nfs-lock does not work (No such file or directory). it does not need to be enabled since rpc-statd.service is static.<\/p>\n
# systemctl enable nfs-idmap
\nIn RHEL7.1 (nfs-utils-1.3.0-8.el7) this does not work (No such file or directory). it does not need to be enabled since nfs-idmapd.service is static.<\/p>\n
3. Start the NFS services:<\/p>\n
# systemctl start rpcbind
\n# systemctl start nfs-server
\n# systemctl start nfs-lock
\n# systemctl start nfs-idmap
\n4. Check the status of NFS service:<\/p>\n
# systemctl status nfs
\n5. Create a shared directory:<\/p>\n
# mkdir \/test
\n6. Export the directory. The format of the \/etc\/exports file is :<\/p>\n
dir client1 (options) [client2(options)…]
\nClient options include (defaults are listed first) :
\nro \/ rw :
\na) ro : allow clients read only access to the share.
\nb) rw : allow clients read write access to the share.
\nsync \/ async :
\na) sync : NFS server replies to request only after changes made by previous request are written to disk.
\nb) async : specifies that the server does not have to wait.
\nwdelay \/ no_wdelay
\na) wdelay : NFS server delays committing write requests when it suspects another write request is imminent.
\nb) no_wdelay : use this option to disable to the delay. no_wdelay option can only be enabled if default sync option is enabled.
\nno_all_squash \/ all_squash :
\na) no_all_squash : does not change the mapping of remote users.
\nb) all_squash : to squash all remote users including root.
\nroot_squash \/ no_root_squash :
\na) root_squash : prevent root users connected remotely from having root access. Effectively squashing remote root privileges.
\nb) no_root_squash : disable root squashing.<\/p>\n
Example :<\/p>\n
# vi \/etc\/exports
\n\/test *(rw)
\n7. Exporting the share :<\/p>\n
# exportfs -r
\n-r re-exports entries in \/etc\/exports and sync \/var\/lib\/nfs\/etab with \/etc\/exports. The \/var\/lib\/nfs\/etab is the master export table. Other options that can be used with exportfs command are :<\/p>\n
-a : exports entries in \/etc\/exports but do not synchronize with \/var\/lib\/nfs\/etab
\n-i : ignore entries in \/etc\/exports and uses command line arguments.
\n-u : un-export one or more directories
\n-o : specify client options on command line
\n8. Restart the NFS service:<\/p>\n
# systemctl restart nfs-server
\nConfiguring NFS client<\/p>\n
1. Install the required nfs packages if not already installed on the server :<\/p>\n
# rpm -qa | grep nfs-utils
\n# yum install nfs-utils
\n2. Use the mount command to mount exported file systems. Syntax for the command:<\/p>\n
mount -t nfs -o options host:\/remote\/export \/local\/directory
\nEample :<\/p>\n
# mount -t nfs -o ro,nosuid remote_host:\/home \/remote_home
\nThis example does the following:
\n\u2013 It mounts \/home from remote host (remote_host) on local mount point \/remote_home.
\n\u2013 File system is mounted read-only and users are prevented from running a setuid program (-o ro,nosuid options).<\/p>\n
3. Update \/etc\/fstab to mount NFS shares at boot time.<\/p>\n
# vi \/etc\/fstab
\nremote_host:\/home \t\/remote_home\t nfs \tro,nosuid \t0 \t0
\nFirewalld services to be active on NFS server<\/p>\n
For the NFS server to work, enable the nfs, mountd, and rpc-bind services in the relevant zone in the firewall-config application or using firewall-cmd :<\/p>\n
# firewall-cmd –add-service=nfs –zone=internal –permanent
\n# firewall-cmd –add-service=mountd –zone=internal –permanent
\n# firewall-cmd –add-service=rpc-bind –zone=internal –permanent<\/p>\n","protected":false},"excerpt":{"rendered":"
NFS allows a linux server to share directories with other UNIX clients over network. NFS server exports a directory and NFS client mounts this directory. RHEL 7 supports two version of NFS \u2013 NFSv3 and NFSv4.<\/p>\n
NFS server and RPC processes<\/p>\n
starting the nfs-server process starts the NFS server and other RPC processes. RPC processes […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[73],"tags":[],"_links":{"self":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/6702"}],"collection":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6702"}],"version-history":[{"count":1,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/6702\/revisions"}],"predecessor-version":[{"id":6703,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/6702\/revisions\/6703"}],"wp:attachment":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6702"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6702"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6702"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}