IBM Support

IBM Cloud VPC Regional File Storage (RFS) File share mounting fails onto AIX

Troubleshooting


Problem

When attempting to mount an IBM Cloud VPC Regional File Storage (RFS) file share on an AIX system using NFSv4, the operation fails with the error 'A route to the remote host is not available' initially. 
After adjusting the NFS domain on the AIX client to match the VPC domain, the mount command fails again with 'vmount: invalid argument'. 
The issue arises because the AIX NFS client only supports NFSv4.0, while the RFS file share is exported via NFSv4.1, which is not compatible.

Symptom

Admins are unable to mount an RFS file share on an AIX system. When attempting to mount using NFSv4, the error '1831-009 9.62.148.42 not in hosts database' and 'A route to the remote host is not available' is encountered. 

/home/root] mount -v nfs -o vers=4 [PII REMOVED (IP Address)]:/D91C781D9D6C45899EFB47A940A65068/portfolio /bh/portfolio
mount: 1831-009 [PII REMOVED (IP Address)] not in hosts database
mount: 1831-008 giving up on:
[PII REMOVED (IP Address)]:/D91C781D9D6C45899EFB47A940A65068/portfolio
A route to the remote host is not available.

After changing the NFS domain on the client to match the NFS domain on the server, it throws this error

mount -v nfs -o vers=4 [PII REMOVED (IP Address)]:/D91C781D9D6C45899EFB47A940A65068/portfolio /bh/portfolio
vmount: invalid argument

When trying to mount specifying NFSv3, this error occurs

'server 9.xx.xxx.xx not responding:
RFC: 1832-018 Port mapper failure -
RPC: 1832-008 Timed out' occurs.


The issue is due to the RFS file share being exported via NFSv4.1 only, while AIX NFS client only supports NFSv4.0 in addition to NFSv2 and 3.

Cause

No technical cause found. The issue is due to a compatibility limitation: the AIX NFS client only supports NFSv4.0, while the IBM Cloud VPC Regional File Storage (RFS) File share is exported only via NFSv4.1. The customer was advised to follow updates on the IBM Ideas portal.

Diagnosing The Problem

  1. Investigate the error message 'mount: 1831-009 9.62.148.42 not in hosts database' and identify the need to check the NFS domain setting.
  2. Run 'chnfsdom' to check the NFS domain on the AIX client and compare it with the VPC domain.
  3. Change the NFS domain on the AIX client to match the VPC domain.
  4. Attempt to mount the RFS file share again and observe the new error 'vmount: invalid argument'.
  5. Investigate the NFS version supported by the AIX NFS client and the RFS file share, identifying that AIX supports NFSv4.0 while RFS file share is exported via NFSv4.1.
  6. Advise the customer to vote and follow updates on the IBM ideas portal for potential future support of NFSv4.1: https://ideas.ibm.com/ideas/AIX-I-719

Resolving The Problem

The issue was caused by the AIX NFS client supporting only NFSv4.0, while the RFS file share was exported via NFSv4.1. To resolve:
1. Changed the NFS domain on the AIX client to match the VPC domain using the command 'chnfsdom'.
2. Attempted to mount the RFS file share using NFSv4.
3. Acknowledged that the AIX NFS client does not support NFSv4.1.
4. Admins are advised to vote and follow updates on the IBM ideas portal: https://ideas.ibm.com/ideas/AIX-I-719.

Document Location

Worldwide

[{"Business Unit":{"code":"BU070","label":"IBM Infrastructure"},"Product":{"code":"SS6QJ7","label":"IBM Power Virtual Server"},"ARM Category":[],"ARM Case Number":"TS022153362","Line of Business":{"code":"LOB68","label":"Power HW"}},{"Type":"MASTER","Line of Business":{"code":"LOB08","label":"Cognitive Systems"},"Business Unit":{"code":"BU058","label":"IBM Infrastructure w\/TPS"},"Product":{"code":"SWG10","label":"AIX"},"ARM Category":[{"code":"a8m0z000000cvyTAAQ","label":"Communication Applications-\u003ENFS\/NFSV4\/PCNFS"}],"Platform":[{"code":"PF002","label":"AIX"}],"Version":"5.3.0;6.1.0;7.1.0;7.2.0;7.3.0"}]

Document Information

Modified date:
21 May 2026

UID

ibm17273542

Page Feedback