Hi, really confused! I'm using redhat as3 with two internal scsi drives mirrored in hardware RAID 1 for the o/s install. ok so the problem is, I have three identical servers all attached to an emc san with fibre channel. When I do fdisk -l on each server and look at the internal disks they all show /dev/sda partition apart from one server where it shows /dev/sde partition. This in itself wouldn't be a problem, but when I add luns from my array and reboot the problem server, it changes to the system drive to /dev/sdsomeotherstring seemingly randomly. This sometimes stops the server from booting completely as it can't mount some partitions like /usr, /etc and /tmp etc. The fstab file uses labels for all the partitions instead of the device name, but somehow the server manages to boot sometimes and not others. None of the san luns are system luns or bootable. Does anyone have any idea what is going on? I would really appreciate some help as I'm tearing what little hair I have out.

Tony

but some different is my issue just meet in MultiOS ,SuSE +RedHAt
my PC disk can be shown as the IDE device in SuSE,but in the Redhat they all be shown as SCSI disks

I don`t know why is this issue occures.
have you sovled your problems?

ray

Nope still not solved - linux seems to be allocating disk devices incorrectly somehow. Sounds different to your problem as it's all within one o/s, and changes randomly on reboot. Some kind of scsi device scanning issue maybe. I don't know how to troubleshoot this one!

Tony

Ok I solved it. (with a little help from support). The scsi drivers were being loaded in the wrong order in /etc/modules.conf. It was loading the fibre channel driver first, so it was discovering luns from the array before the internal disk luns and assigning /dev devices accordingly. I changed the order to load the internal scsi megaraid driver first, saved it and ran makinitrd to make a new booting kernel. Everything was fine after that! Just thought I'd let you know.

Tony