NFS service common troubleshooting

NFS, the full name is Network File System, Chinese called network file system, is a part of the distributed file system of Linux and UNIX systems, which can share remote file system on different networks. Developed by Sun Microsystems, NFS is now one of the standards for file services (RFC1904, RFC1813). Its biggest function is to allow computers of different operating systems to share data through the network, so NFS can be regarded as a file server. The disadvantage of NFS is that its read and write performance is worse than the local hard drive. First, NFS service common troubleshooting

The NFS service has failed, mainly to check the reasons from the following aspects:

(1) Check if the load of NFS client and server is too high, Server Whether the network between the client and the client is normal;

(2) Check the correctness of the /etc/exports file;

(3) Restart the NFS and portmap services if necessary;

(4) Run the following command to restart portmap and NFS: /etc/init.d/portmap restart/etc/init.d/nfs restart/etc/init.d/rpcbind restart (in RHEL/CentOS 6.x) Chkconfig portmap onchkconfig nfs onchkconfig rpcbind on (in RHEL/CentOS 6.x)

Note: In RHEL/CentOS 6.x, the portmap service is renamed to the rpcbind service; by the way, the rpcbind service is also a graphic The key infrastructure of the interface, does not start this service, can not start the graphical desktop.

(5) Check whether the mount command or /etc/fstab syntax on the client is correct;

(6) Check whether the kernel supports NFS and RPC services.

Normally installed Linux systems will support NFS and RPC services by default, unless you recompile the kernel yourself and do not select the nfs support option to compile. Second, NFS common troubleshooting methods

1, The rpcbind failure error

Fault phenomenon:

nfs mount: server1:: RPC: Rpcbind failure

RPC: Timed Out

nfs mount: retrying: /mntpoint

Cause:

First, it may be because the client's hosts file has the wrong IP address and host name. Or node name combination;

Second, the server temporarily stops serving due to overload.

2, The server not responding error

Phenomenon:

NFS server server2 not responding, still trying

Cause:

First, the network is unreachable, use the ping command to detect it.

Second, the server is shut down.

3, The NFS client fails a reboot error

Phenomenon:

After starting the client, it stops and displays the following message:

Setting Default interface for multicast: add net 224.0.0.0: gateway:

client_node_name.

Cause:

Fg is not successful in the mount option of etc/vfstab Mount the resource on the server, change it to bg or comment out the line until the server is available.

4, The service not responding error

Phenomenon:

nfs mount: dbserver: NFS: Service not responding

nfs mount: retrying: /mntpoint

Cause:

First, the current level is not level 3, use who-r to view, use init 3 to switch.

Second, the NFS Server daemon does not exist, use ps -ef