An exception occurs when an application on an AIX host invokes the getdirent function to access the NFS share.

Problem Description

V3 storage devices are mounted to AIX hosts using NFS shares. Operations on NFS shared directories fail in the following scenarios:

1. Use FTP to access the NFS share and run ls to display the file name containing wildcard characters.

2. Run the chmod command to modify the file permission.

The causes of the problem in the two scenarios are the same. The following uses scenario 1 as an example to describe the problem: AIX host B mounts an NFS share of the V3 storage. On AIX host A, use ftp the IP address of host B to access the directory where the NFS share resides. When ls is used to enumerate files that contain wildcard characters, a search failure is returned.

Symptom Description

When AIX host A uses FTP to access the NFS share of AIX host B, a file containing wildcard characters in ls fails, as shown in the following figure.

Cause

The AIX host uses the 32-bit interface getdirent to query directories. By default, the file ID returned by the storage device is 64-bit (the NFS protocol specifies that the value is 64-bit). As a result, the host fails to enumerate directories.

For details, see the IBM official website at

Location Method

1. Run the trust command on the AIX host to which the NFS share is mounted to trace the system call of the host, as shown in the following figure:

a) Run the ps –ef | grep ftp command on host B to query the FTP process ID.

b) Run the trust –p process ID command on host B. The process ID is the number in the red box in step a).

c) Log in to host A and run the ls command with wildcard characters in the NFS shared directory in the FTP environment.

d) Save the system call information monitored on host A.

2. Analyze the trust invoking information to check whether the host uses the getdirent interface to query directories and whether the function returns EOVERFLOW, as shown in the following figure. If yes, the problem is caused.

Solution

Log in to the CLI through the storage management port and run the following commands:

2. Run the following command to query the file system ID:

3. Run the following command to configure the storage file system to be compatible with the 32-bit file system invoking interface. The value in red box 1 is the value obtained in step 2, and the value in red box 2 is fixed to yes.

4. Unmount the NFS share mount point on the host and mount it again.

Post-Recovery Check

When you use FTP on AIX host A to access the NFS share on AIX host B, the ls file containing wildcard characters can be properly displayed.

Appendix

NA