RAID - 5 , OS Booting Problem

Hello

What was going on before this issue? Was the system working fine with an installed OS and then you encountered the voltage error, did you move it to another location and experienced these issues, are you performing initial setup, or something else?

Most modern operating systems should contain the necessary drivers for the controller. If you are installing an older OS then you will need to load a controller driver.

There are a lot of possibilities, rather than writing several paragraphs speculating about possible issues it would be much easier if you provided more information as to what the situation is.

Thanks

This is a very common problem with the 2850. Most likely the RAID/SCSI mode was reset with the CMOS battery change and resetting the mode in the RAID BIOS to RAID could resolve your issue. Assuming you were in RAID mode before the change and nothing was written to the disks while in SCSI mode, you should be able to change it back without losing data. Although, you would have to assume at this moment that you may have to restore from backup.

The BIOS default is SCSI mode, so if there is an issue with the CMOS battery, the settings would have reverted from RAID to SCSI. Again, ASSUMING you were using RAID before, you can safely ignore the scary messages about data loss when switching to RAID. Being in SCSI mode would absolutely cause the OS not to boot.

Thanks all of you for quick response.

Yes, from many years, Server was working fine before this CMOS error.

I tried to change from SCSI to RAID using Integrated Devices option in BIOS before posting query in this dell forum. But after restarting of server when it ask that “by switching the mode from SCSI to RAID data will be lost, press Y to continue and for cancelation press any other key”. I did not press “Y” key to avoid losing our very important data.

Now question is that should I need to press “Y” to boot the OS? And what is the possibility of data lose in this scenario?  

Anytime to switch from SCSI mode to RAID mode or vice versa you will receive this message. The truth is , this is a common scenario when resetting BIOS as the default is SCSI mode. Assuming you had a Raid array before this scenario, it means that you were in RAID mode , and it is really your only choice to hit Y and see what you have. The only possibility of DATA loss is if you were really in SCSI mode before this happened, although if you were, there is no reason it would not be booting in the current SCSI mode.

Like I said you can safely ignore the message if you were running RAID before.

Also, the mere switching modes does not cause data loss ... it is if you do any disk operation after switching to the wrong mode that causes data loss.

After switching mode from SCSI to RAID using Integrated Devices option in BIOS, now it is showing following message “Press for BMC Setup within 5 sec” and cursor is blinking….. still not able to boot to OS

Then your OS is damaged ... also not unusual when your system crashes. Boot to your OS media to attempt to repair.

how can i verify that raid is working fine and data is present ......

Not necessarily.

Boot to your Windows disc, choose Repair to see if it recognizes an OS install, then change drive to the OS drive, and do a DIR to see if the folder structure is seen.