Re: External hdd changing device node mid-use

[Alex Mestiashvili <alexander.mestiashvili@biotec.tu-dresden.de>]

Panayiotis Karabassis wrote:
> I have an external usb 2.0 LG hard disk. It is part of an md array 
> which is in turn part of an lvm array. The strange thing is that while 
> the drive is in use, it will suddenly change device nodes, for example 
> from /dev/sda to /dev/sdb. This will cause the md driver to mark it as 
> faulty. This is very disruptive. Why is this happening and how to 
> solve it?
Might be it is better to write a special udev rule and name this usb 
drive with some non-standard way

like /dev/usb_drive1 for example

for example these are the rules for 2x sas drives on my workstation


/etc/udev/rules.d/61-persistent-storage.rules

KERNEL=="sd?", SUBSYSTEM=="block" , ATTR{removable}=="0" , 
ENV{ID_BUS}=="scsi", ATTRS{vendor}=="HITACHI "  SYMLINK+="sasdrive%n"

KERNEL=="sd?", SUBSYSTEM=="block" , ATTR{removable}=="0" , 
ENV{ID_BUS}=="scsi",  ATTRS{vendor}=="FUJITSU "  SYMLINK+="sasdrive2%n

so they appear as /dev/sasdrive
and /dev/sasdrive2


http://reactivated.net/writing_udev_rules.html

Regards ,
Alex