Re: When should we use "hdparm" ?

Hi,

I also not sure why we don't use power off/on control any more with
the SATA/IDE newer devices.

Thanks,
ranran

On Fri, Jul 13, 2018 at 10:48 AM, Ran Shalit <[email protected]> wrote:
> On Fri, Jul 13, 2018 at 10:25 AM, Greg KH <[email protected]> wrote:
>> On Fri, Jul 13, 2018 at 09:29:50AM +0300, Ran Shalit wrote:
>>> Hello,
>>>
>>> We have some old system (2.4 kernel) which use hot swap with sata
>>> (IDE) , but using commands such as:
>>> hdparm -U 0
>>> hdparm -R 0 0x1f0 ...
>>>
>>> But in newer system HW&SW we never use these commands when removing
>>> and inserting sata.
>>
>> What do you do instead?
>>
> I just mount and unmount partition.
> In the old system, we manually power the the storage device after
> instert and (poweroff on remove) , and then used the hdparm
> register/unregister comands.
> Without the hdparm commands the device doesn't exist in /dev , i.e. we
> must do this register/unregister in the old HW &old kernel.
>
>
>>> Why was it used once and why is it not used in newer system ?
>>
>> In the 2.4 kernel there was not kernel support for hot-swap devices like
>> this, so you had to "manually" do it with these types of commands.
>>
>>> Is it that newer system do this somehow automatically ? Where ?is it
>>> done, in SW or HW ?
>>
>> How exactly are you swapping your ide drives today?
>>
>
> With newer HW&SW  don't do now any hot swapping, just mount/unmount.
> Seems that insert/remove id done under power (?),
> I just try to understand why the newer system (HW&SW) don't need to
> use these commands any more (hdparm).
>
>> And the 2.4 kernel was over a decade ago, hopefully you have upgraded
>> your hardware since then :)
>>
>> thanks,
>>
>> greg k-h