Personal tools

HPC:NFS configuration

From hpcwiki

Revision as of 22:32, 21 April 2018 by Hfrancot (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

NFS configuration to provide HPCLab DAS access to worker nodes

Raw guide contents

1 Preliminary Note I have fresh installed CentOS 7 server, on which I am going to install the NFS server. My CentOS server have hostname server1.example.com and IP as 192.168.0.100

If you don't have a CentOS server installed yet, use this tutorial for the basic operating system installation. Additionally to the server, we need a CentOS 7 client machine, this can be either a server or desktop system. In my case, I will use a CentOS 7 desktop with hostname client1.example.com and IP 192.168.0.101 as client. I will run all the commands in this tutorial as root user.

2 At NFS server end As the first step, we will install these packages on the CentOS server with yum:

yum install nfs-utils

Now create the directory that will be shared by NFS:

mkdir /var/nfsshare

Change the permissions of the folder as follows:

chmod -R 755 /var/nfsshare
chown nfsnobody:nfsnobody /var/nfsshare

We use /var/nfsshare as shared folder, if we use another drive such as the /home directory, then the permission chnges will cause a massive permissions problem and ruin the whole hierarchy. So in case we want to share the /home directory then permissions must not be changed. Next, we need to start the services and enable them to be started at boot time.

systemctl enable rpcbind
systemctl enable nfs-server
systemctl enable nfs-lock
systemctl enable nfs-idmap
systemctl start rpcbind
systemctl start nfs-server
systemctl start nfs-lock
systemctl start nfs-idmap

Now we will share the NFS directory over the network a follows:

nano /etc/exports

We will make two sharing points /home and /var/nfsshare. Edit the exports file as follows:

/var/nfsshare    192.168.0.101(rw,sync,no_root_squash,no_all_squash)
/home            192.168.0.101(rw,sync,no_root_squash,no_all_squash)

Note 192.168.0.101 is the IP of client machine, if you wish that any other client should access it you need to add the it IP wise other wise you can add "*" instead of IP for all IP access.

Condition is that it must be pingable at both ends.

Finally, start the NFS service:

systemctl restart nfs-server

Again we need to add the NFS service override in CentOS 7 firewall-cmd public zone service as:

firewall-cmd --permanent --zone=public --add-service=nfs
firewall-cmd --permanent --zone=public --add-service=mountd
firewall-cmd --permanent --zone=public --add-service=rpc-bind
firewall-cmd --reload

Note: If it will be not done, then it will give error for Connection Time Out at client side.

Now we are ready with the NFS server part.

3 NFS client end In my case, I have a CentOS 7 desktop as client. Other CentOS versions will also work the same way. Install the nfs-utild package as follows:

yum install nfs-utils

Now create the NFS directory mount points:

mkdir -p /mnt/nfs/home
mkdir -p /mnt/nfs/var/nfsshare

Next, we will mount the NFS shared home directory in the client machine as shown below:

mount -t nfs 192.168.0.100:/home /mnt/nfs/home/

It will mount /home of NFS server. Next we will mount the /var/nfsshare directory:

mount -t nfs 192.168.0.100:/var/nfsshare /mnt/nfs/var/nfsshare/

Now we are connected with the NFS share, we will crosscheck it as follows:

df -kh

[root@client1 ~]# df -kh

Filesystem                    Size  Used Avail Use% Mounted on
/dev/mapper/centos-root        39G  1.1G   38G   3% /
devtmpfs                      488M     0  488M   0% /dev
tmpfs                         494M     0  494M   0% /dev/shm
tmpfs                         494M  6.7M  487M   2% /run
tmpfs                         494M     0  494M   0% /sys/fs/cgroup
/dev/mapper/centos-home        19G   33M   19G   1% /home
/dev/sda1                     497M  126M  372M  26% /boot
192.168.0.100:/var/nfsshare   39G  980M   38G   3% /mnt/nfs/var/nfsshare
192.168.0.100:/home           19G   33M   19G   1% /mnt/nfs/home
[root@client1 ~]#

So we are connected with the NFS share.

Now we will check the read/write permissions in the shared path. At client enter the command:

touch /mnt/nfs/var/nfsshare/test_nfs

So we successfully configured an NFS-share.

4 Permanent NFS mounting We have to re-mount the NFS share at the client after every reboot. Here are the steps to mount it permanently by adding the NFS-share in /etc/fstab file of client machine:

nano /etc/fstab

Add the entries like this:

[...]
192.168.0.100:/home    /mnt/nfs/home   nfs defaults 0 0
192.168.0.100:/var/nfsshare    /mnt/nfs/var/nfsshare   nfs defaults 0 0

Note 192.168.0.100 is the server NFS-share IP address, it will vary in your case.

This will make the permanent mount of the NFS-share. Now you can reboot the machine and mount points will be permanent even after the reboot.

Cheers, now we have a successfully configured NFS-server over CentOS 7 :)

5 Links CentOS : http://www.centos.org/