Is there something similar to a udev rule in solaris express dev. ed.

crisostomo_enrico · 08-16-2007, 02:22 AM

Hi.

I was wondering if there's something similar to an udev rule in Solaris Express Dev. Ed. hotplugging infrastructure. The problem to solve is always the same: I want to plug an external USB disk and want to be sure that I do have a well defined /dev entry (maybe this isn't required to get the job done) and that filesystems in the device gets mounted always in the same directories.

I checked official documentation (819-2723 - devices and filesystems) but I didn't find the answer.

Another quick question: is there any drawback in doing a ZFS pool on an USB removable device?

Thanks,
Enrico.

crisostomo_enrico · 08-17-2007, 04:03 AM

Well, maybe it's not the answer I was looking for (it's only valid for ZFS while I was looking for something more general) but here it is:

Quote:

(817-2271, p. 45) Disks are identified both by their path and by their device ID, if available. This method allows devices to be reconfigured on a system without having to update any ZFS state. If a disk is switched between controller 1 and controller 2, ZFS uses the device ID to detect that the disk has moved and should now be accessed using controller 2. The device ID is unique to the drive's firmware. While unlikely, some firmware updates have been known to change device IDs. If this situation happens, ZFS can still access the device by path and update the stored device ID
automatically. If you inadvertently change both the path and the ID of the device, then export and re-import the pool in order to use it.

So I would think that, even if I created a pool on c5t0d0, if controller changes (because I change the USB port I'm plugging the device into), then ZFS will be able to correctly identify the device.

Bye,
Enrico.

jlliagre · 08-17-2007, 07:18 AM

Solaris express uses now HAL (Hardware Abstraction Layer) so removable device get mounted automatically in /media/<name>. This is for at least pcfs, hsfs and UFS. You shouldn't care about the device name.

ZFS is managed differently and indeed doesn't rely about the device used. You can create a raid from several removable disks, unplug then plug all of them again in different ports. The system should recover from the shuffle gracefully.