Dear all, actually I installed CentOS 5.4 x86_64 on 11 new Dell R710 servers. It is required to use 5.4 to be covered by the NetApp Interoperability Matrix for use of Snapdrive. All systems spit out the error message mpt2sas0: failure at drivers/scsi/mpt2sas/mpt2sas_scsih.c:4637/_scsih_add_device()! at boot time. In dmesg the complete SCSI initialization logging appears as follows: SCSI subsystem initialized mpt2sas version 01.101.00.00 loaded scsi0 : Fusion MPT SAS Host GSI 22 sharing vector 0x5A and IRQ 22 ACPI: PCI Interrupt 0000:03:00.0[A] -> GSI 33 (level, low) -> IRQ 90 PCI: Setting latency timer of device 0000:03:00.0 to 64 mpt2sas0: 64 BIT PCI BUS DMA ADDRESSING SUPPORTED, total mem (24544400 kB) mpt2sas0: PCI-MSI-X enabled: IRQ 98 mpt2sas0: iomem(0xdf2b0000), mapped(0xffffc20000040000), size(65536) mpt2sas0: ioport(0xfc00), size(256) mpt2sas0: sending diag reset !! [...] mpt2sas0: diag reset: SUCCESS mpt2sas0: Allocated physical memory: size(1125 kB) mpt2sas0: Current Controller Queue Depth(490), Max Controller Queue Depth(3439) mpt2sas0: Scatter Gather Elements per IO(128) mpt2sas0: LSISAS2008: FWVersion(02.15.63.00), ChipRevision(0x02), BiosVersion(07.01.09.00) mpt2sas0: Protocol=(Initiator,Target<6>mpt2sas0: Dell PERC H200 Integrated: Vendor(0x1000), Device(0x0072), SSVID(0x1028), SSDID(0x1F1E) ), Capabilities=(Raid,TLR,EEDP,Snapshot Buffer,Diag Trace Buffer,Task Set Full,NCQ) mpt2sas0: sending port enable !! mpt2sas0: host_add: handle(0x0001), sas_addr(0x5842b2b0194dce00), phys(8) mpt2sas0: failure at drivers/scsi/mpt2sas/mpt2sas_scsih.c:4637/_scsih_add_device()! mpt2sas0: port enable: SUCCESS Vendor: Dell Model: Virtual Disk Rev: 1028 Type: Direct-Access ANSI SCSI revision: 06 scsi 0:1:0:0: RAID1: handle(0x004f), wwid(0x04adb846d46d5f0a), pd_count(2), type(SSP) scsi 0:1:0:0: qdepth(128), tagged(1), simple(1), ordered(0), scsi_level(7), cmd_que(1) SCSI device sda: 285474816 512-byte hdwr sectors (146163 MB) sda: Write Protect is off sda: Mode Sense: 03 00 00 08 SCSI device sda: drive cache: write through SCSI device sda: 285474816 512-byte hdwr sectors (146163 MB) sda: Write Protect is off sda: Mode Sense: 03 00 00 08 SCSI device sda: drive cache: write through sda: sda1 sda2 sda3 sd 0:1:0:0: Attached scsi disk sda Vendor: FUJITSU Model: MBA3147RC Rev: D306 Type: Direct-Access ANSI SCSI revision: 05 scsi 0:0:0:0: SSP: handle(0x000a), sas_addr(0x500000e1150ca882), device_name(0x0000000000000000) scsi 0:0:0:0: SSP: enclosure_logical_id(0x5842b2b0194dce00), slot(1) scsi 0:0:0:0: qdepth(254), tagged(1), simple(1), ordered(0), scsi_level(6), cmd_que(1) Vendor: FUJITSU Model: MBA3147RC Rev: D306 Type: Direct-Access ANSI SCSI revision: 05 scsi 0:0:1:0: SSP: handle(0x000b), sas_addr(0x500000e1150ca9c2), device_name(0x0000000000000000) scsi 0:0:1:0: SSP: enclosure_logical_id(0x5842b2b0194dce00), slot(0) scsi 0:0:1:0: qdepth(254), tagged(1), simple(1), ordered(0), scsi_level(6), cmd_que(1) In the source code of the mpt2sas.ko module http://www.takatan.net/lxr/source/drivers/scsi/mpt2sas/mpt2sas_scsih.c?v=2.6.18-164.el5;a=x86_64 the code part responsible for the error messages is 4633 /* check if this is end device */ 4634 device_info = le32_to_cpu(sas_device_pg0.DeviceInfo); 4635 if (!(_scsih_is_end_device(device_info))) { 4636 printk(MPT2SAS_ERR_FMT "failure at %s:%d/%s()!\n", 4637 ioc->name, __FILE__, __LINE__, __func__); 4638 return 0; 4639 } I am not sure what that should tell me. I can not detect any misfunction once the systems are up and running, nor any further error loggings. Any clue about the severity of that mpt2sas check and failure note? Best regards Alexander