SATA II LUN Distribution between SPs in same RAID Group

chrisp,
The guidance for assigning the LUNs within a certain RAID Group to a single SP is applicable to the 2Gbit/sec DAE-ATA implementation (usually found on CX-series arrays). It does not carry over to the 4Gbit/sec DAE3P/DAE4P implementation that was introduced on CX3-series arrays. Essentially - go by the enclosure type. This is reflected in the "EMC CLARiiON Best Practices Guide for Fibre Channel Storage" document (available on Powerlink) page 34 in the latest edition, although the wording there currently highlights the array type.

Regards,
DGM

Thanks for the quick response....
The way you explained it was the way I understood it. Once you get on the DAE3P/DAE4P, you can ignore the old requirements about LUN to SP in same RG for ATA Drives (SATA II).

The article that made me question that was
emc157746

It shows the environments that are affected as CX and CX3 Series. I think it reads that way is because you can support the older DAE2P-ATA models in the newer CX3 Series.
Reference emc154373

Essentially, if you have a CX3 Series with the older DAE2P-ATAs (2Gbps) you still need to comply with all LUNs in the same RG to same SP requirements. If you have a CX3 with the Newer DAE3P/DAE4P (3/4 Gbps) you can distribute the LUNs in the same RG to different SPs without a performance issue.

Do you agree with this conclusion?
If so EMC should be more specific and reference the DAE model for this requirement instead on the CX Series.

Thanks again for your time and input.

Yes, go by the enclosure type; as you note, the older 2Gbit/sec DAE-ATA enclosures are still supported by the CX3-series (e.g. if a CX700 was converted to a CX3-80, it can retain the existing enclosures). We'll cross-check the documentation for consistency and clarity.

Regards,
DGM

Thanks again for your help...

It would be appreciated if EMC can produce a clearer definition on this.