Setting up NFS4 on CentOS

First: install server software and start it

yum install nfs-utils nfs-utils-lib system-config-nfs
yum install nfs-utils nfs4-acl-tools portmap
chkconfig nfs on
chkconfig portmap on
service nfs start
echo 'portmap:ALL' >> /etc/hosts.deny
echo 'portmap:192.168.1.0/24' >> /etc/hosts.allow
service portmap start

run the firewall gui and turn on NFS4 (2049)

Second: export the directories to be shared

system-config-nfs #will launch the gui

• can use 192.168.4.0/24 for all of subtree
• General options
  ☒ Disable subtree checking
  ☒ Sync on request
  ☒ Hide filesytems beneath
  Set FSID to 0 (1,2,3 etc for each share) for NFS4
• User Access:
  ☒ Treat remote root user as local root (reduces security, but needed if home directories are mounted)
• or alternatively you can edit the files by hand:
  • note that the second line is for a filesystem that is mounted under the first and must be ‘unhidden’

vi /etc/exports
/home           192.168.1.0/24(rw,sync,no_subtree_check,fsid=0)
/home/submount  192.168.1.0/24(rw,sync,no_subtree_check,nohide)

exportfs -a #or service nfs reload ?

Install Client

apt-get install -y nfs-common
echo '192.168.4.120  sv  sv.isnew.org' >> /etc/hosts
//sudo apt-get install sysv-rc-conf //netfs not needed on Ubuntu
//sysv-rc-conf

• Test with

mount -t nfs4 sv:/ /mnt

• Add to fstab:

sv:/    /home  nfs4   soft,intr,rsize=8192,wsize=8192,nosuid

Make sure users on client have same uid/gid as on server

cat /etc/group # see what they are on the server
groupadd -g 504 office
groupadd -g 505 supervisor

#now add users
useradd -g 504 -u 503 -G 505 doug
passwd doug

#for exisiting users
usermod -g 504 -u 501 andrewf
usermod -G 505 andrewf

Troubleshooting permissions

• As per ubuntuforums.org/…owthread.php

1. Make sure a FQDN is set up on the server
   • in /etc/sysconfig/network, /etc/hosts and with the hostname command
2. Check /etc/idmapd.conf is configured with proper domain = cfaw.info
   • This must be the same on clients and servers
3. As per serverfault.com/…nd-gids-match edit the file /etc/default/nfs-common and set
   NEED_IDMAPD= yes

• restart CentOS server with: service portmap restart; service nfs restart

Here are some useful links:

• www.cyberciti.biz/…nfiguration —best resource
• www.centos.org/…US/ch-nfs.html
  • using the gui: www.centos.org/…er-export.html
  • www.centos.org/…nt-config.html
• nfs.sourceforge.net/…on_issues Excellent troubleshooting guide
• www.unix-info.org/…wto29;.txt good howto for NFS4