I'm trying to setup a new diskless solution with ubuntu 12.04 without any success. I followed this howto: https://help.ubuntu.com/community/DisklessUbuntuHowto But the initramfs seems not to be able to mount my nfs share. On my server side: My /etc/exports /srv/nfs4 192.168.0.0/24(fsid=0,rw,no_subtree_check) /srv/nfs4/nfsroot 192.168.0.0/24(rw,no_root_squash,no_subtree_check,fsid=1,nohide,insecure,sync) I'm able to mount my nfs share on standard Ubuntu installation without any problem. I can mount my nfs on any client with those commands: mount 192.168.0.3:/nfsroot /mnt or mount 192.168.0.3:/srv/nfs4/nfsroot /mnt My /tftpboot/pxelinux.cfg/default config file is DEFAULT vmlinuz-3.5.0-25-generic root=/dev/nfs initrd=initrd.img-3.5.0-25-generic nfsroot=192.168.0.3:/nfsroot ip=dhcp rw I also tried DEFAULT vmlinuz-3.5.0-25-generic root=/dev/nfs initrd=initrd.img-3.5.0-25-generic nfsroot=192.168.0.3:/srv/nfs4/nfsroot ip=dhcp rw. What I got in initramfs: With the setting [nfsroot=192.168.0.3:/nfsroot] Diskless output: mount call failed - server replied: Permission denied On Syslog of my nfs server: rpc.mountd[1266]: refused mount request from 192.168.0.10 for /nfsroot (/): not exported With the setting [nfsroot=192.168.0.3:/srv/nfs4/nfsroot] Diskless output: mount: the kernel lacks NFS v3 support On Syslog of my nfs server I got: Mar 11 14:03:06 BootFromLan rpc.mountd[1266]: authenticated mount request from 192.168.0.10:834 for /srv/nfs4/nfsroot (/srv/nfs4/nfsroot) Mar 11 14:03:06 BootFromLan rpc.mountd[1266]: refused unmount request from 192.168.0.10 for /root (/): not exported