Ygtjki

I am trying to mount hdfs on my local machine(ubuntu) using nfs by following the below link:--

https://www.cloudera.com/documentation/enterprise/5-2-x/topics/cdh_ig_nfsv3_gateway_configure.html#xd_583c10bfdbd326ba--6eed2fb8-14349d04bee--7ef4

So,at my machine I installed nfs-common using:-

sudo apt-get install nfs-common

Then,before mounting I have ran these commands:-

rpcinfo -p 192.168.170.52
program vers proto port service
100000 4 tcp 111 portmapper
100000 3 tcp 111 portmapper
100000 2 tcp 111 portmapper
100000 4 udp 111 portmapper
100000 3 udp 111 portmapper
100000 2 udp 111 portmapper
100024 1 udp 48435 status
100024 1 tcp 54261 status
100005 1 udp 4242 mountd
100005 2 udp 4242 mountd
100005 3 udp 4242 mountd
100005 1 tcp 4242 mountd
100005 2 tcp 4242 mountd
100005 3 tcp 4242 mountd
100003 3 tcp 2049 nfs

showmount -e 192.168.170.52
Export list for 192.168.170.52:
/ *

after that i tried mounting the hdfs using:--

sudo mount -t nfs -o vers=3,proto=tcp,nolock 192.168.170.52:/ /mnt/hdfs_mount/

But i was getting this error:---

mount.nfs: mount system call failed

Then i googled for the problem and installed nfs-kernel-server,portmap using

sudo apt-get install nfs-kernel-server portmap

After executing the above command,the output for:---

rpcinfo -p 192.168.170.52

is:--

192.168.170.52: RPC: Port mapper failure - Unable to receive: errno 113 (No route to host)

and for

showmount -e 192.168.170.52

is:---

clnt_create: RPC: Port mapper failure - Unable to receive: errno 113 (No route to host)

Also the output for:--

sudo service nfs start

comes out to be:--

Failed to start nfs.service: Unit nfs.service not found.

Please help me with this.

I was testing this issue on CentOS 7. When you encounter such a problem you have to dig deeply.

The problem:

clnt_create: RPC: Port mapper failure - Unable to receive: errno 113 (No route to host)

is related to firewall. The command showmount -e IP_server shows all mounts that are available on server. This command works fine, but you have to be careful which port to open. It does not get through the firewall if only port 2049 has been opened. If the firewall on the NFS server has been configured to let NFS traffic get in, it will still block the showmount command. To test if you disable firewall on server you should get rid of this issue.

So those ports should be open on server:

firewall-cmd --permanent --add-service=rpc-bind
firewall-cmd --permanent --add-service=mountd
firewall-cmd --permanent --add-port=2049/tcp
firewall-cmd --permanent --add-port=2049/udp
firewall-cmd --reload

Additional test 2049/NFS port for availability.

• 
  semanage port -l | grep 2049 - returns SELinux context and the service name


• netstat -tulpen | grep 2049