AIX Tip of the Week

Subject: How to Mount a Remote CD-ROM Using NFS

Audience: Administration

Date: May 21, 2004

LPARs typically do not have a dedicated CD-ROM for installing software and updates. To get around this, I typically mount a remote CD-ROM as a NFS filesystem. The attached "How to" provides instructions for doing so.

PS This may be cumbersome or not work at all for multi-volume CD's. In these situations, my first strategy would be to copy the CD's to disk, and NFS mount the filesystem on the client.


How to NFS Mount a cdrom Filesystem

Following are the steps required to mount a CD-ROM as a cdrom filesystem, export the NFS filesystem from the server and NFS mount the filesystem on the client. This document applies to AIX Versions 4.3 and above. On the server On the client Troubleshooting -------------------------------------------------------------------------------

On the server

1. Check the status of portmap and the NFS daemons: o Enter lssrc -s portmap. o Enter lssrc -g nfs. o If they are not active, start them by running startsrc -s portmap and then startsrc -g nfs.

2. Mount the CD-ROM: o Enter mkdir /cdrom to create a mount point, if one does not already exist. o Load the CD into the CD-ROM drive. o Enter smitty cdrfs. o Select Add a CDROM File System. o Select your device from the F4 list. o Enter the mount point you just created for MOUNT POINT. o Enter names of client servers allowed root access (Req'd if accessing via root id on client) o If you want the filesystem to mount on a reboot, change Mount AUTOMATICALLY at system restart to yes. NOTE: If you specify yes for Mount AUTOMATICALLY at system restart, you must have media in the CD-ROM drive when you reboot or the mount will fail. o Enter mount /cdrom.

3. To add the filesystem for NFS exporting: o Enter smitty mknfsexp. o Enter the PATHNAME of the directory to export (for example, /cdrom). o Change the MODE of export directory to read-only. o Enter the HOSTS & NETGROUPS allowed client access. o Enter HOSTS allowed root access. o Press Enter to export the filesystem. NOTE: If you are going to be installing on the client machine, you MUST enter the client name for HOSTS allowed root access.

4. Verify that the filesystem is exported: o Enter showmount -e and find it in the list.

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On the Client

1. Check the status of portmap and the NFS daemons: o Enter lssrc -s portmap. o Enter lssrc -g nfs. o If they are not active, start them by running startsrc -s portmap and then startsrc -g nfs.

2. Verify that the server has the filesystem exported: o Enter showmount -e . NOTE: will be the hostname of the server.

3. Create the directory you will be using to access the software. o Enter mkdir /cdrom.

4. To NFS mount the filesystem on the client: o Enter smitty mknfsmnt. o Enter the PATHNAME of the mount point (for example, /cdrom). o Enter the PATHNAME of the remote directory (for example, /cdrom). o Enter the HOST where the remote directory resides. NOTE: HOST will be the hostname of the server. o Change the MODE for this NFS file system to read-only. o Press enter to NFS mount the filesystem.

On AIX 4.x BOS installation CD-ROMs and most LPP CD-ROMs, the install images are now located in /cdrom/usr/sys/inst.images. On some LPP CD-ROMs, the install images are located in /cdrom. To check which directory the install images are on, check for the existence of a .toc file in the directory. Once you have determined the directory with the .toc file, use the full pathname of the directory as your in SMIT when you perform your install. -------------------------------------------------------------------------------

Troubleshooting

Look for the following errors:

mount: 1831-011 access denied for ... mount: 1831-008 giving up on ...

If they occur, try the following suggestions:

1. Make sure that the client's hostname and IP address are resolvable by the server. Also, make sure that the server's hostname and IP address are resolvable by the client. You can do so by running the following:

On the server:

host host

The output of these lines has to match EXACTLY.

On the client:

host host

The output of these lines has to match EXACTLY. 2. On the client, enter netstat -in. If there is more than one network interface, make sure all IP addresses of the client are resolvable by the server. You can do this by running (on the server):

host

Execute this command for each IP address listed in the netstat -in output. 3. If you are still getting errors:

On the server, enter smitty rmnfsexp. o Enter the PATHNAME of the exported directory (for example, /cdrom). o Press Enter to remove the directory from the exports list. o Enter umount /cdrom. o Enter rmdir /cdrom. o Return to step 1 of the section "On the server". If you still cannot get the CD-ROM NFS mounted, contact your AIX support center for further assistance.



Bruce Spencer,
baspence@us.ibm.com

May 21, 2004