[CentOS] Setting CDROM parms

Robert kerplop at sbcglobal.net
Sun Jan 3 16:29:03 UTC 2010



Mr. X wrote:
>
> --- On Sat, 1/2/10, Robert<kerplop at sbcglobal.net>  wrote:
>
>    
>> From: Robert<kerplop at sbcglobal.net>
>> Subject: [CentOS] Setting CDROM parms
>> To: "CentOS mailing list"<centos at centos.org>
>> Date: Saturday, January 2, 2010, 6:23 PM
>> My apologies in advance for asking
>> such an elementary question.  I
>> called myself searching the Installation Guide and
>> Deployment Guide,
>> with no success.
>> The situation is that I bought a Lite-On ATAPI iHAP122 that
>> will not
>> burn DVDs unless I use hdparm to turn dma off. I bought
>> that drive
>> because it was a rare beige drive.  Until I can find a
>> decent DVD burner
>> and/or get a Windows machine put together strictly for
>> doing BIOS
>> updates, running with dma disabled seems to be the best
>> solution.
>> (hdparm -d0 /dev/hdb )
>> So, my question is, where should I script the command
>> without having to
>> become root each time I wat to burn a DVD?
>>
>>      
> Robert,
>
> The -k flag to hdparm allows you to persist your settings across a reset.
>    
I'll try that.
> Did you try to elevate the dma to the highest supported by the device?
>    
Actually, I didn't try very much at all with hdparm because of all the 
"caution", "warning", "dangerous", etc.

> --------------------- info ------------
> sudo hdparm -I /dev/cdrom
>
> /dev/cdrom:
>
> ATAPI CD-ROM, with removable media
>          Model Number:       Slimtype DVDRW SOSW-852S
>          Serial Number:
>          Firmware Revision:  PSU2
> Standards:
>          Supported: CD-ROM ATAPI-2
> Configuration:
>          DRQ response: 50us.
>          Packet size: 12 bytes
> Capabilities:
>          LBA, IORDY(cannot be disabled)
>          DMA: mdma0 mdma1 mdma2 udma0 udma1 *udma2
>               Cycle time: min=120ns recommended=120ns
>          PIO: pio0 pio1 pio2 pio3 pio4
>               Cycle time: no flow control=227ns  IORDY flow control=120ns
> --------------- end snip --------------
>    
Mine looks like this:


hdparm -I /dev/hdb

/dev/hdb:

ATAPI CD-ROM, with removable media
         Model Number:       ATAPI   iHAP122   8
         Serial Number:
         Firmware Revision:  UL05
Standards:
         Likely used CD-ROM ATAPI-1
Configuration:
         DRQ response: 50us.
         Packet size: 12 bytes
Capabilities:
         LBA, IORDY(cannot be disabled)
         DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 *udma4
              Cycle time: min=120ns recommended=120ns
         PIO: pio0 pio1 pio2 pio3 pio4
              Cycle time: no flow control=240ns  IORDY flow control=120ns

> On Centos, you can run k3b to handle burning easily.
Yes, I usually use k3b; chose cli for this plea for help because the 
command and error output appear in one convenient wad.

> The only caveat is

> sometimes on KDE installs you will have the hdc unavailable for exclusive access. You can fix that by
> $sudo killall kio_audiocd
>
> see http://bugs.kde.org/135669
>    

> One more thing. If you want to demo the Knoppix 6, save burning the DVD and boot the ISO directly with qemu-kvm or qemu with kqemu.
>
>    
>> sudo qemu -kernel-kqemu -cdrom KNOPPIX_V6.0.1CD-2009-02-08-EN.iso -m 384 -usb -boot d -net nic,model=rtl8139 -net user&
>>      
> put the above on one line. You need 2 packages to run qemu in this fast mode.
>
> $ rpm -qa | grep qemu
> dkms-kqemu-1.4.0-0.1.pre1.nodist.rf
> qemu-0.10.5-1.el5.rf
>    
Good info. As far as KNOPPIX in my example, the name kinda leaped out at me:
[rj at madeleine tmp]$ find /home/rj -depth -type f -size +3G -name "*.iso"
/home/rj/KNOPPIX_V6.2DVD-2009-11-18-EN.iso
[rj at madeleine tmp]$

Thanks for the pointers!




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