This page describes how to mount NFS partition inside VE.
Contents
NFS server
Currently OpenVZ kernel doesn't include kernel NFS server support. However you are still able to use user space NFS server inside VE.
NFS client
Preparations
Prerequisites
You will need the following software:
- vzctl version 3.0.13 or higher (do
vzctl --version) - kernel version 2.6.18-028test006 or higher (2.6.18-028stab* will do), or any recent RHEL5-based or 2.6.20-based kernel.
Note: In all the kernels earlier than 028stab038, kernel NFS support can be given to a VE by setting:
sunrpc.ve_allow_rpc = 1
fs.nfs.ve_allow_nfs = 1
kernel.ve_allow_kthreads = 1
This can be done by adding the above lines into /etc/sysctl.conf on the hardware node, and then running sysctl -p.
Prepare the HN
For NFS mounts to work in the VEs with the RHEL5-based kernels you must enable kernel threads in the VE by setting "kernel.ve_allow_kthreads=1" in /etc/sysctl.conf
# modprobe nfs
Prepare the VE
To allow a VE use NFS filesystem, you will need to start it with "nfs" feature enabled. If the VE is running while you set the --features "nfs:on", you will need to reboot it.
# vzctl set 101 --features "nfs:on" --save # vzctl start 101
After this you may see nfs in /proc/filesystems
# vzctl exec 101 cat /proc/filesystems
ext3
ext2
nodev rpc_pipefs
nodev proc
nodev nfs
nodev sysfs
nodev tmpfs
nodev devpts
Mounting NFS
Assuming that you already have NFS server set up at 192.168.0.1:/nfs_pub mounting will be simple
# vzctl enter 100 # mkdir /nfs # mount -t nfs 192.168.0.1:/nfs_pub /nfs # cat /proc/mounts simfs / simfs rw 0 0 proc /proc proc rw 0 0 sysfs /sys sysfs rw 0 0 devpts /dev/pts devpts rw 0 0 nfs /nfs nfs rw,vers=3,rsize=32768,wsize=32768,hard,proto=tcp,timeo=600,retrans=2,sec=sys,addr=192.168.0.1 0 0
For more details on how to setup NFS mount see NFS-client HOWTO
Known issues
There are quite a few parameters in NFS, so sometimes it doesn't work due to misconfiguration. We created a separate page for discribing such situation: NFS doesn't work