CentOS - Jan 2009 - e-sata

Hi,

Does anybody has any experience with e-sata on CentOS5.2?

- How fast is it? Same as an internal sata?
- Does it support sata-2?
- Does it "hot-plug" like a USB?

-- 
Thanks
http://www.911networks.com
When the network has to work

On Sun, January 25, 2009 5:02 pm, centos at 911networks.com
wrote:
> Does anybody has any experience with e-sata on CentOS5.2?
>
> - How fast is it? Same as an internal sata?
> - Does it support sata-2?
> - Does it "hot-plug" like a USB?
I use one ExpressCard eSATA II controller with a laptop under CentOS 5. 
The controller requires reboot in order to be recognized (at least I don't
know a way to make it work any other way), but the disks are hot-pluggable
just like with USB.  No idea how the speed compares to internal SATA.

Marko

centos at 911networks.com wrote:
> Hi,
> 
> Does anybody has any experience with e-sata on CentOS5.2?
> 
> - How fast is it? Same as an internal sata?
> - Does it support sata-2?
> - Does it "hot-plug" like a USB?
The 'E' just means the connector comes out the back.  Otherwise it is 
the same as internal with the same options that depend on the controller 
model and driver.   Most, but not all SATA controllers support hot-plug 
but I think it needs to be done at the drive level, not the cable to the 
case so the connectors can enforce the right order of connections on the 
power and data side.

-- 
   Les Mikesell
    lesmikesell at gmail.com

Hi,

On Sun, Jan 25, 2009 at 17:02,  <centos at 911networks.com>
wrote:
> Does anybody has any experience with e-sata on CentOS5.2?
Yes.
> - How fast is it? Same as an internal sata?
Same as internal. Just the connector is different.
> - Does it support sata-2?
> - Does it "hot-plug" like a USB?
Depends on the adapter you get.

First time I got an Adaptec eSATA II RAID 1225SA and it turns out
that, even though they use a standard Silicon Image 3132 (IIRC) that
is supported by the sata_sil24 native driver, they ship it with a
non-default PCI ID, so the default kernel in CentOS 5 does not
recognize it. I opened a bug for it and I got the patch to include
that PCI ID in CentOS-plus kernel, so if you use that kernel the
adapter will work. Anyway, I would stay away of it if possible.
http://www.adaptec.com/en-US/support/raid/sataii/AAR-1225SA/

Second time around I got one from StarTech.com, it also uses the
sata_sil24 native driver, and this one works out of the box. I just
had a small glitch to have it recognized by the server the first time
around, which was fixed by moving it to another PCIe slot (not sure
why it did not work on the first one I tried). I can recommend this
one:
http://www.startech.com/item/PEXESATA2-2-Port-PCI-Express-eSATA-Controller-Card.aspx

Both work with SATA II (3Gbps) and both support "hot-plug", only in
some cases you may need to force scanning (with a command such as
"echo 1 >/sys/class/scsi_host/hostX/scan"), I'm not sure if you
have
to do that always or not.

Here some information on Linux SATA drivers, very useful:
http://linuxmafia.com/faq/Hardware/sata.html
Stay away from those that need proprietary drivers.

I still would like to find an adapter that works with the Linux ahci
driver, since that seems to be the best one, at least from information
in that web page, but so far no luck finding them...

HTH,
Filipe