[opensuse] External USB hotswap HDDs
Hi Thanks to those of you who made suggestions when I could not get 10.2 to recognise a CoolGear USB removable HDD. It turned out the problem was with the USB hub inside the external case drawing too much current and lowering the voltage to marginal levels. It was drawing its current from the server USB socket despite the fact that the external case had its own power supplied from the wall AC socket. My hardware man cured the problem by connecting the +5v regulated supply from the power circuitry to the hub (via the key switch). Turns out the box was an earlier model - the manufacturer now supplies boxes with the same mod. This prompts 2 questions though. Any advice would be gratefully accepted. 1. Is it OK to just unplug the device without using umount? My practice hitherto has been to: 1. plug the cable into both the server and the case. 2. put the disktray in the case. 3. Switch on the power to the case 4. switch on the tray keyswitch, and wait for the lights to settle 5. Access the device via /media/disk (or whatever shows up in mount for /dev/sdb1 This is not as complex as it sounds, and probably not too important. Now comes the part that bothers me: To remove the disc, I have been doing the following: 1. umount /dev/sdb1 (or whatever) 2. switch off the disktray 3. remove the disktray In fact there is a keylock. You cannot remove the disktray unless you unlock with the key. The question: Is step 1 necessary or unnecessarily cautious. Question 2 How can you reconfigure SuSE 9 to imitate the behaviour of 10.2 with regards to mount points (i.e. /media/disk instead of /media/verylonghardwarebasednamewith\spaces? regards John O'Gorman -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Tuesday 2007-05-01 at 13:35 +1200, John O'Gorman wrote:
Thanks to those of you who made suggestions when I could not get 10.2 to recognise a CoolGear USB removable HDD.
It turned out the problem was with the USB hub inside the external case drawing too much current and lowering the voltage to marginal levels. It was drawing its current from the server USB socket despite the fact that the external case had its own power supplied from the wall AC socket. My hardware man cured the problem by connecting the +5v regulated supply from the power circuitry to the hub (via the key switch). Turns out the box was an earlier model - the manufacturer now supplies boxes with the same mod.
Curious. I hinted at power, but I was still far from the mark...
This prompts 2 questions though. Any advice would be gratefully accepted.
1. Is it OK to just unplug the device without using umount?
Better not. The general answer is "no".
To remove the disc, I have been doing the following:
1. umount /dev/sdb1 (or whatever) 2. switch off the disktray 3. remove the disktray
In fact there is a keylock. You cannot remove the disktray unless you unlock with the key. The question: Is step 1 necessary or unnecessarily cautious.
Check with the command "mount". If you see a "sync" option applied to the device (all used partitions) then it is safe - usually. If you don't see it, then it is certainly unsafe. I always use "umount whatever" to be on the safe side. It's better to waste some seconds than spend a day repairing a badly damaged disk.
Question 2
How can you reconfigure SuSE 9 to imitate the behaviour of 10.2 with regards to mount points (i.e. /media/disk instead of /media/verylonghardwarebasednamewith\spaces?
There was a trick to mount on a fixed mount point name. It was published on the SDB, and I did some investigating at the time that I wrote to the list - I used 9.1 or 9.3 - but I can't find that email right now on a quick search. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFGNxgHtTMYHG2NR9URAtB7AJwPqHYk7SkK6mznm1ZGTLBDSe6AGwCgixdx geS0fwEA+JbQZiUr8qxZaGs= =SJyX -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
On Tue, May 1, 2007 02:35, John O'Gorman wrote:
1. Is it OK to just unplug the device without using umount? No.
Most of the time, if the disc has been sitting on idle for a while, you'll get away with it (but your filesystem will be marked as NOT CLEAN). BUT: I have noticed that SUSE tends to keep data in RAM for quite a long time. Maybe it's just because my notebook has 2GB, so it's more liberal with caching, but nevertheless. Often, all discs are idle, minutes after I copied stuff to an external disc. Typing sync then takes at least a couple of seconds. If all data were already committed to the filesystem on the external disc, sync should have been instant. So be careful of that. If you cannot get it to unmount, at least to a sync before you yank it out.
How can you reconfigure SuSE 9 to imitate the behaviour of 10.2 with regards to mount points (i.e. /media/disk instead of /media/verylonghardwarebasednamewith\spaces?
Read up on udev. It's going to be a fair bit of surgery though. Hans -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Tuesday 2007-05-01 at 14:57 +0100, Hans du Plooy wrote:
How can you reconfigure SuSE 9 to imitate the behaviour of 10.2 with regards to mount points (i.e. /media/disk instead of /media/verylonghardwarebasednamewith\spaces?
Read up on udev. It's going to be a fair bit of surgery though.
udev, that was it. You reminded me of the thread: http://lists.opensuse.org/opensuse/2005-04/msg00819.html http://lists.opensuse.org/opensuse/2005-05/msg01965.html There it mentions the one the OP should be interested in: http://portal.suse.com/sdb/en/2005/05/dkukawka_hal_mountpoints.html Mounting to Static Mount Points But that was 9.3 - I don't know how close is 9.0 to that approach. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Made with pgp4pine 1.76 iD8DBQFGN4NUtTMYHG2NR9URAka9AJ9OMcLmht7Tny0x3y7O4NBAeMcFkQCaAsI5 9lLduAnZh+kNBmkSIkFk300= =NURB -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org
participants (3)
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Carlos E. R. -
Hans du Plooy -
John O'Gorman