[CentOS] Port multiplier support in megaraid* module for LSI LOGIC LSI00042 PCI-X SATA II Controller?

Mike Fedyk mfedyk at mikefedyk.com
Mon Nov 27 22:57:54 UTC 2006

I have tried many permutations of search terms in google and I haven't
been able to find any confirmation that the megaraid* modules in centos4
supports port multipliers/multiplexers.

Here is a link to the controller I have in mind at newegg:

In case anyone is interested, here is what my research has turned up
when looking for external JBOD SATA enclosures:

I'm just looking for a hot swap JBOD enclosure, so anything over $1000
USD is out of the question.  Luckily, I found a few meeting that

The DS-1220 is rackmountable, holds 12 drives and uses two port 
multipliers.  The only drawbacks I can see is that it looks like they 
could've fit 15 drives with three multipliers, and two drives need 
direct connections to the controller.  That's 4 esata ports used ( 2 x 5
port multiplier + 2 direct to hard drive ).


The SC-SATA12RM is rackmountable, uses 4 multi-lane SAS connectors and 
holds 12 drives.  Having full bandwidth to each drive can have its 
advantages for streaming reads and writes, but the seeky workload I 
expect won't benefit much from the extra theoretical bandwidth.  In 
order to save on sata controller port usage, I'd probably have to get a 
few port multipliers.


The SC-SAT10PM holds 10 drives, uses two port multipliers, connects to 
the SATA HBA with 2 esata connections (and may be rack mountable with 
some customizations -- I need to check further).  Because of the area 
the server and storage will be in, the enclosure doesn't strictly need 
to be rack mountable.


Here are some links to esata to sata, sata multilane/sas to four
internal sata ports, etc. port converters:

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