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VMware ESXi5.5 host can not mount RHEL6.5 storage how to deal with, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain in detail for you, people with this need can come to learn, I hope you can gain something.

System environment

System platform: RHEL LINUX 6.5

NFS Server IP:192.168.2.19

Shared directory: / mnt/parastor

VMWARE EXSI:5.5

Description of the problem: Mount a shared directory in the NFS server of a RHEL Linux5.5 virtual machine in DATASTORE on VMWARE EXSI5.5, as follows:

Error stack

Failed to call "HostDatastoreSystem.CreateNasDatastore" of object "datastoreSystem-29" on vCenter Server "VM-1".

NFS failed to mount 192.168.2.19:/mnt/parastor: the NFS server does not support MOUNT version 3 through TCP.

(the corresponding prompt for the English version is NFS server does not support MOUNT version 3 over TCP)

This is because the services on the NFS server are transferred using the default UDP protocol, while VMware requires that TCP be used, so modify the configuration file / etc/nfsmount.conf and uncomment the Defaultproto=tcp line. Of course, sometimes, if you modify this item and cannot mount it successfully, please check as follows:

Whether the firewall is off or not

Service iptables stop

Chkconfig iptables off

2. Whether the nfs service is started

Chkconfig nfs on

Service nfs start

Check the exports file

Cat / etc/exports

/ mnt/parastor 192.168.110.* (rw,sync,no_root_squash)

IV. Modify / etc/nfsmount.conf

Remove the comments from the following lines (default is that udp,esxi requires tcp,esxi to use mount v3)

Defaultproto=tcp

Proto=tcp

Mountproto=tcp

Mounvers=3

5. Then restart the following services:

Service rpcbind start

Service nfs restart

Finally, it is found that the nfs is mounted successfully.

Note: RPC must be started first. RPC is Remote Procedure Call Protocol (remote procedure call Protocol), and RPCBIND is used to replace the portmap component in the previous version. To put it simply, the purpose of RPCBIND is to bind different services to corresponding ports in order to support interoperability between machines. Principle supplement: the main function of RPC is to specify the port number corresponding to each NFS function, and report back to the client, so that the client can connect to the correct port. When the server starts NFS, it will randomly access several ports and actively register with RPC, so RPC can know the NFS function corresponding to each port, and then RPC can ensure the success of NFS connection by regularly using port 111to listen for client requests and report back the correct port on the client!

In addition, the explanation of FSID parameters:

To share a directory through NFS, you first need to define the directory in the / etc/exports file and use the parameters of fsid=0. Only one directory can be shared when using the fsid=0 option, which will become the root directory of the NFS server. )

See the following original explanation in English:

Fsid=num

This option forces the filesystem identification portion of the file handle and file attributes used on the

Wire to be num instead of a number derived from the major and minor number of the block device on which the

Filesystem is mounted. Any 32 bit number can be used, but it must be unique amongst all the exported

Filesystems.

This can be useful for NFS failover, to ensure that both servers of the failover pair use the same NFS file

Handles for the shared filesystem thus avoiding stale file handles after failover.

Some Linux filesystems are not mounted on a block device; exporting these via NFS requires the use of the

Fsid option (although that may still not be enough).

The value 0 has a special meaning when use with NFSv4. NFSv4 has a concept of a root of the overall

Exported filesystem. The export point exported with fsid=0 will be used as this root.

NFS needs to mark each exported file system. Typically use the UUID of the file system (if the file system has one), or the device number of the device on which the file system is stored (if the file system is stored on the device). Not all file systems are stored on the device, and not all file systems have UUID,NFS that requires precise identification of the file system, so you need to use the fsid option.

For NFSv4, there is an excellent file system that is the root of all exported file systems. Identified by fsid=root or fsid=0. Identify other file systems, using a small integer (any 32-bit number can be used, but it must be unique among all exported file systems), or any UUID that contains 32 hexadecimal numbers and punctuation.

The UUID setting is not supported in Linux kernel version 2.6.20 and earlier.

Background knowledge:

NFS is the abbreviation of Network File System, that is, the network file system. A protocol for distributed file systems developed by Sun and published in 1984. The function is to enable different machines and different operating systems to share individual data with each other through the network, and to let applications access the data located in the server disk through the network. It is a method to realize disk file sharing among Unix-like systems.

The basic principle of NFS is to "allow different clients and servers to share the same file system through a set of RPC". It is independent of the operating system and allows systems with different hardware and operating systems to share files together.

NFS relies on RPC protocol in the process of file transfer or information transfer. RPC, remote procedure call (Remote Procedure Call) is a mechanism that enables clients to execute programs in other systems. NFS itself does not provide protocols and functions for information transmission, but NFS allows us to share data through the network, because NFS uses some other transport protocols. And these transport protocols use this RPC function. It can be said that NFS itself is a program using RPC. Or NFS is also a RPC SERVER. So start the RPC service wherever NFS is used, whether it's NFS SERVER or NFS CLIENT. In this way, SERVER and CLIENT can correspond to PROGRAM PORT through RPC. The relationship between RPC and NFS can be understood this way: NFS is a file system, while RPC is responsible for the transfer of information.

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