Re: [gentoo-user] Re: Questions about SATA and hot plugging.

[Mark Knecht]

On Thu, Dec 16, 2010 at 10:05 AM, Dale <rdalek1967@×××××.com> wrote:
> Mark Knecht wrote:
>>
>> On Thu, Dec 16, 2010 at 7:29 AM, Volker Armin Hemmann
>> <volkerarmin@××××××××××.com>  wrote:
>> <SNIP>
>>
>>>
>>> again, the hardware to hotplug is built into every sata connector. What
>>> is
>>> left is the controller not getting confused and the driver.
>>>
>>>
>>
>> Every SATA connector? External connectors yes. Internal connectors no.
>>
>>
>>>
>>> AHCI as a standard says yes to hoplugging. So as long as you use a AHCI
>>> compliant sata controller you can hotplug.
>>>
>>
>> Interested readers should be _VERY_ careful about listening to
>> previous advice. The major difference between the internal and
>> external SATA cables&  connectors, a ***particularly*** important part
>> of hotplugging, is that the external connector ensures that ground is
>> connected before the signals. This ensures that in the case of static
>> electricity the drive becomes grounded to the computer which is done
>> to eliminate ESD (electro static discharge) events which will damage
>> either the drive or the controller. (Depending n which is charged.)
>>
>> If you are using an internal power supply and have drive power already
>> attached when you hotplug an internal cable then likely you will be
>> just fine.
>>
>> If, on the other hand, you have a SATA drive sitting on a bench using
>> a separate power supply then hotplugging with an internal cable is not
>> recommended.
>>
>> Hope this helps,
>> Mark
>>
>>

Hi Dale

>
> I'm not saying that this is good advice but this is what my mobo manual
> says.  If I have the BIOS set to AHCI, then all the ports are hot pluggable.
>  That includes the internal ones.  My mobo design is about a year old so
> this may not apply to older ones but that is what the manual says.  Just
> because I am to chicken to try doesn't mean it doesn't work tho.  I'm to
> chicken to use the one marked external too.
>

Cool. As I said when I first replied to this thread that's not always
the case. My Intel DH55HC has 6 SATA ports but only 2 are eSATA
compatible.

If you are hot plugging internal drives to internal connectors and
they are hooked to the same power supply as your motherboard then it
should be safe even using internal cables that fit the motherboard
connectors. Note that those connectors aren't all that strong so you
should be careful not to break one.

> I moved my data drive over from the old rig last night.  I got out the
> flashlight and magnifying glass and gave all the connectors a good looking
> over.  They all have that L shape connector which is usually what external
> connectors have.  That is according to what I have read anyway.  All the
> connectors are the same on my mobo, both internal and external.
>
> It appears to me that with my mobo, there is no "internal" connectors.  They
> are just all SATA and hot pluggable.
>
> Dale

Hold on there. SATA and eSATA connectors are definitely different. If
your case came with a cable hooked to the eSATA connector then that
cable is taking care of the difference already. Try plugging an
internal SATA cable into the eSATA connector on your case. You'll find
out pretty quickly that they don't work.

A proper eSATA connector doesn't have the 'L'. It has small flanges
that stick out to the sides. (Or mine do anyway!!)

No reason to be scared of eSATA hotplugging. Works fine and it's
designed to be robust.
- Mark