Using an HP-UX disk in a Linux system

[Juan Ramon Alvarez]

I have a disk in a HP 712/80. How can I use this disk in a Linux Computer. I have tried several times but I don't know what is the filesystem type I must specify in the linux mount command

[Matjaz Obstetar]

Hi!

There is a few ways to mount a HP-UX disk in a Linux system. On HP-UX you should have started Samba or NFS. If you have Samba you try:
mount -t smbfs //hostname/device /mountpoint
If you have different users on Linux and HP-UX you add option -o username=yourusername,password=yourpassword

For NFS the mount command is:
mount -t nfs hostname.domainname:/dir /mountpoint
On HP-UX in /etc/exports must be written the file sistem which you want to mount in Linux.

Regards,

Matjaz

[Juan Ramon Alvarez]

Thank you for your answer, but my problem is that the HP9000 712/80 is broken. I need attach the disk to the Linux computer dirctly.

[Tim Malnati]

There are several issues to deal with, so I'll attempt to cover each one.

First, I don't have any HP workstation info handy, but I thing that the drive is probably SE SCSI. If this is the case you will need to get a controller card that supports SCSI2 and install it and attach the drive making sure there are no target conflicts (probably not if the drive and the controller are the only scsi devices).

The next thing to deal with is having the kernel see the controller. This is very dependent on the actual manufacturer/model of the card that you install. My guess is that you already have an IDE based drive in the system so you can have the kernel access the drive by loading a kernel module during the boot process (but you can also do it with lilo if it's built into the kernel). The easiest way to accomplish this is to add the module and device info into /etc/modules.conf; something like:

alias scsi_hostadapter
options =""

On a RedHat distribution, the info needed for these parameters are listed in the Reference Guide Appendix. After this is complete you need to load the kernel module with 'modprobe -s scsi_hostadapter'. If all is well the disk device will be reported. The best way to handle having the module loaded at boot is with a short script in /etc/rc.d/init.d that invokes the modprobe command.

So far, so good; you can now at least access the drive. The question next to deal with is, do you need the old data that's on the drive? This can be a problem. Linux now supports LVM (sort of) and journaling with ext3, but if either will work on a imported drive is something I have not tried (and haven't heard of any success stories either). There is direct support for HFS file systems, but any HFS volumes were probably defined with LVM on the HP box. You have nothing to loose by attempting with these new utilities in Linux, but otherwise you will probably end up reconfiguring it to ext2.

[Juan Ramon Alvarez]

Thank you, Tim. My problem is that I need the data. My disk is recognized by the system. The problem is that mount command don't accept none of the filesystem types. But I don't have ext3 and VFS types.

[Tim Malnati]

ext3 is the Linux version of journaled file systems that is supposed to be very close to VxFS. You didn't mention your Linux distribution, but I know that both ext3 and LVM have been ported and are running on most of the major Linux players distributions. The problem is that neither product is fully native to the 2.2 kernel. The 2.4 kernel will have everything needed to allow booting directly with these options, but that is still a way down the street. The way around this is to add them in as a module similarly to the method I mentioned before with modules.conf amd modprobe. You will need the 2.4 header files though (and they are working fine with my 2.2.16 kernel). I have seen a variety of posts on the usenet that suggests that both functions are working well, but I have seen several negative comments regarding using them in combination with any form of Linux software raid or striping.