[OpenAFS-devel] The Xserve saga: happy conclusion (more or lesss)

[Valerio Luccio]

I got the OpenAFS server to run on the Apple Xserve running OS X 10.2. 
Here's what it seems to be the problem: the server comes with 4 disks 
(in the configuration I purchased) which can be RAIDed using software 
RAID. You can either do striping or mirroring, but not both. The 
partition that I was trying was made of two mirrored disks. When the 
afsd daemon tries to mount it, somehow the mapping between the RAID set 
and the mount point does not work. If I format the disks to be 
individual UNIX/format disks, the server does the mounting without a 
problem. I'm now tring to see if the mounting works with a striped RAID, 
it seems to, but I'm not done testing.

A few notes, comments, questions ....

Is there anyone who uses an software RAID set as their AFS partition ? 
I'm curious to see if the problem is with software RAIDs in general or 
with Apple's implementation of it.

Apple is about to release an XRaid storage device to go with the Xserve 
(in the next few weeks) which will have hardware  RAID. I don't know if 
the problem will persist with that as well.
 
Running the server under OS X does not work out-of-the-box. By default 
OS X mounts all of it's disks, except for the OS disk, under 
"/Volumes/xxxxx" and if you have more than one disk each time you boot 
up the device name of the disks change (using two RAID sets, sometime it 
calls the OS disk "/dev/disk4" and the second set "/dev/disk5", some 
other times the other way around). I think that this is due to the OS 
creating the devices in parallel and, therefore, who ever gets there 
first gets the lower number. Add to this the fact that if you mount by 
hand the "/vicepa" partition, the information must be correctly 
contained in the NetInfo database. Currently I do the following, by 
hand: find out the name of my data disk (with mount); unmount the disk 
from "/Volumes/vicepa" and remount it in "/vicepa"; delete the current 
information from the NetInfo database (using niutil); store the new info 
in the NetInfo database (using niload). I'm going to set up the server 
so that it does not mount the data disk at boot up and, hopefully, that 
will mean that the name will remain constant. Then I'm going to modify 
the AFS startup script so that it does the rest automatically. Once I 
have it running properly I will send it to OpenAFS to be posted (maybe 
with a few lines of installation instructions for the Mac).

For the time being I'm done. Thanks to all who replied.

-- 
Valerio Luccio                  (212) 998-8736
Center For Neural Science       4 Washington Place, Room 935
New York University             New York, NY 10003

        "In an open world, who needs windows or gates?"