https://community.hpe.com/t5/proliant-servers-netservers/ml570-multiple-p400-controllers/m-p/804898#M13474 No, the ML570 G4's 18-bays may only be connected to one channel of an SA-P400. If you need additional channels, add an external storage array to the ML570 G4 and either a SA-P600 or SA-P800 for 'external' SAS channels. Mon, 18 Jun 2007 08:20:44 GMT Kedd Guyton 2007-06-18T08:20:44Z https://community.hpe.com/t5/proliant-servers-netservers/ml570-multiple-p400-controllers/m-p/804897#M13473 We have an ML570 G4 with 18 internal SAS drives. Currently we have 1 Smart Array P400 controller to handle the disk arrays. We are looking to get improved I/O and thought that adding a 2nd P400 array controller to share the load with the other P400 controller would help us accomplish this. <BR /> <BR /> The problem we think may happen is after looking at the i/o backplate behind the SAS drives themselves, we only see 1 connection which the current P400 is connected to. <BR /> <BR /> So is it possible to split drives 1-9 on 1 controller and drives 10-18 on a second controller and would this give us improved I/O ? Also, how would we go about doing this? <BR /> Thu, 14 Jun 2007 17:07:06 GMT https://community.hpe.com/t5/proliant-servers-netservers/ml570-multiple-p400-controllers/m-p/804897#M13473 Ryan Brace 2007-06-14T17:07:06Z https://community.hpe.com/t5/proliant-servers-netservers/ml570-multiple-p400-controllers/m-p/804898#M13474 No, the ML570 G4's 18-bays may only be connected to one channel of an SA-P400. If you need additional channels, add an external storage array to the ML570 G4 and either a SA-P600 or SA-P800 for 'external' SAS channels. Mon, 18 Jun 2007 08:20:44 GMT https://community.hpe.com/t5/proliant-servers-netservers/ml570-multiple-p400-controllers/m-p/804898#M13474 Kedd Guyton 2007-06-18T08:20:44Z