CentOS - Dec 2007 - libata and PMP (Port Multiplier) support in CentOS

I'm looking at buying a NORCO DS-1220 and it comes with a NORCO 4618
PCI-X card (4 port eSATA, with a port multiplier on the card or the
chassis).  I've been trying to pin down whether or not CentOS will see
all 12 drives, and I haven't seen anything that is definitive.  I see
that the kernel module sata_sil24 supports the SiI3124 chip on the NORCO
4618 card, but I haven't found whether or not the default kernel will
support the SiI3726 (PMP) without the libata-tj patch.

I'm just trying to determine the easiest route to go with minimal cost.
I've found another enclosure that uses 4 mini-SAS connectors, but in
addition to the extra $320 for the enclosure, I'd need to buy a $300
card and at least one $120 cable (either SFF-8088 to SFF-8470 or a
straight SFF-8088).  While this is for at home, I would consider this a
"mission critical" device and don't want a flakey setup, which is
what I
have now...I've become an expert at recovering from a 2 drive failure in
a 4 drive RAID5 setup using mdadm.

Any ideas, suggestions, or authoritative comments?


--Tim
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Timothy Selivanow schrieb:
> I'm looking at buying a NORCO DS-1220 and it comes with a NORCO 4618
> PCI-X card (4 port eSATA, with a port multiplier on the card or the
> chassis).  I've been trying to pin down whether or not CentOS will see
> all 12 drives, and I haven't seen anything that is definitive.  I see
> that the kernel module sata_sil24 supports the SiI3124 chip on the NORCO
> 4618 card, but I haven't found whether or not the default kernel will
> support the SiI3726 (PMP) without the libata-tj patch.
> 
> I'm just trying to determine the easiest route to go with minimal cost.
> I've found another enclosure that uses 4 mini-SAS connectors, but in
> addition to the extra $320 for the enclosure, I'd need to buy a $300
> card and at least one $120 cable (either SFF-8088 to SFF-8470 or a
> straight SFF-8088).  While this is for at home, I would consider this a
> "mission critical" device and don't want a flakey setup,
which is what I
> have now...I've become an expert at recovering from a 2 drive failure
in
> a 4 drive RAID5 setup using mdadm.
> 
> Any ideas, suggestions, or authoritative comments?
> 
> 
> --Tim
AFAIK the RHEL5 kernel does not support the SiI3726 PMP.

I'm running PMP with kernel 2.6.23.1 and the libata-tj patch. The
forthcoming
2.6.24 has PMP natively.

HTH,

Kay