Sorry for the incomplete bug report.
The raid configuration is a common hardware based raid1. Two 1 TB physical disks
provide one logical disk.
Attached is a dmesg report (5.6 stable) after pressing 'S' to get out of the
installer to get a shell.
snip
OpenBSD 5.6 (RAMDISK_CD) #303: Fri Aug 8 00:25:26 MDT 2014
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/RAMDISK_CD
real mem = 8471130112 (8078MB)
avail mem = 8240234496 (7858MB)
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 2.8 @ 0x7abcd000 (76 entries)
bios0: vendor Dell Inc. version 1.0.4 date 08/28/2014
bios0: Dell Inc. PowerEdge R730
acpi0 at bios0: rev 2
OpenBSD 5.6 (RAMDISK_CD) #303: Fri Aug 8 00:25:26 MDT 2014
dera...@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/RAMDISK_CD
real mem = 8471416832 (8078MB)
avail mem = 8240513024 (7858MB)
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 2.8 @ 0x7abcd000 (76 entries)
bios0: vendor Dell Inc. version 1.0.4 date 08/28/2014
bios0: Dell Inc. PowerEdge R730
acpi0 at bios0: rev 2
acpi0: sleep states S0 S5
acpi0: tables DSDT FACP MCEJ WD__ SLIC HPET APIC MCFG MSCT PMCT SLIT SRAT SSDT
SSDT SSDT PRAD SPCR DMAR HEST BERT ERST EINJ
acpimadt0 at acpi0 addr 0xfee0: PC-AT compat
cpu0 at mainbus0: apid 0 (boot processor)
cpu0: Intel(R) Xeon(R) CPU E5-2623 v3 @ 3.00GHz, 3300.46 MHz
cpu0:
FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUSH,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE,SSE3,PCLMUL,DTES64,MWAIT,DS-CPL,VMX,SMX,EST,TM2,SSSE3,FMA3,CX16,xTPR,PDCM,PCID,DCA,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,DEADLINE,AES,XSAVE,AVX,F16C,RDRAND,NXE,PAGE1GB,LONG,LAHF,ABM,PERF,ITSC,FSGSBASE,BMI1,AVX2,SMEP,BMI2,ERMS,INVPCID
cpu0: 256KB 64b/line 8-way L2 cache
cpu0: apic clock running at 99MHz
cpu at mainbus0: not configured
cpu at mainbus0: not configured
cpu at mainbus0: not configured
cpu at mainbus0: not configured
cpu at mainbus0: not configured
cpu at mainbus0: not configured
cpu at mainbus0: not configured
ioapic0 at mainbus0: apid 8 pa 0xfec0, version 20, 24 pins
ioapic1 at mainbus0: apid 9 pa 0xfec01000, version 20, 24 pins
acpimadt0: unknown apic structure type 7f
acpimadt0: unknown apic structure type 7f
acpimadt0: unknown apic structure type 7f
acpiprt0 at acpi0: bus 255 (UNC0)
acpiprt1 at acpi0: bus 0 (PCI0)
acpiprt2 at acpi0: bus 2 (BR1A)
acpiprt3 at acpi0: bus 3 (BR2A)
acpiprt4 at acpi0: bus 4 (BR2C)
acpiprt5 at acpi0: bus 1 (BR3A)
acpiprt6 at acpi0: bus -1 (BR3B)
acpiprt7 at acpi0: bus 5 (BR3C)
acpiprt8 at acpi0: bus -1 (RP02)
acpiprt9 at acpi0: bus -1 (RP03)
acpiprt10 at acpi0: bus -1 (RP05)
acpiprt11 at acpi0: bus 7 (RP08)
pci0 at mainbus0 bus 0
0:22:0: mem address conflict 0x3303000/0x10
0:22:1: mem address conflict 0x3302000/0x10
pchb0 at pci0 dev 0 function 0 vendor Intel, unknown product 0x2f00 rev 0x02
ppb0 at pci0 dev 1 function 0 vendor Intel, unknown product 0x2f02 rev 0x02
pci1 at ppb0 bus 2
vendor Symbios Logic, unknown product 0x005d (class mass storage subclass
RAID, rev 0x02) at pci1 dev 0 function 0 not configured
ppb1 at pci0 dev 2 function 0 vendor Intel, unknown product 0x2f04 rev 0x02:
msi
pci2 at ppb1 bus 3
em0 at pci2 dev 0 function 0 Intel I350 rev 0x01: msi, address
a0:36:9f:63:cf:ba
em1 at pci2 dev 0 function 1 Intel I350 rev 0x01: msi, address
a0:36:9f:63:cf:bb
ppb2 at pci0 dev 2 function 2 vendor Intel, unknown product 0x2f06 rev 0x02:
msi
pci3 at ppb2 bus 4
em2 at pci3 dev 0 function 0 Intel I350 rev 0x01: msi, address
a0:36:9f:63:d7:50
em3 at pci3 dev 0 function 1 Intel I350 rev 0x01: msi, address
a0:36:9f:63:d7:51
ppb3 at pci0 dev 3 function 0 vendor Intel, unknown product 0x2f08 rev 0x02
pci4 at ppb3 bus 1
em4 at pci4 dev 0 function 0 Intel I350 rev 0x01: msi, address
ec:f4:bb:d3:4f:54
em5 at pci4 dev 0 function 1 Intel I350 rev 0x01: msi, address
ec:f4:bb:d3:4f:55
em6 at pci4 dev 0 function 2 Intel I350 rev 0x01: msi, address
ec:f4:bb:d3:4f:56
em7 at pci4 dev 0 function 3 Intel I350 rev 0x01: msi, address
ec:f4:bb:d3:4f:57
ppb4 at pci0 dev 3 function 2 vendor Intel, unknown product 0x2f0a rev 0x02:
msi
pci5 at ppb4 bus 5
em8 at pci5 dev 0 function 0 Intel I350 rev 0x01: msi, address
a0:36:9f:63:d6:e0
em9 at pci5 dev 0 function 1 Intel I350 rev 0x01: msi, address
a0:36:9f:63:d6:e1
vendor Intel, unknown product 0x2f28 (class system subclass miscellaneous, rev
0x02) at pci0 dev 5 function 0 not configured
vendor Intel, unknown product 0x2f29 (class system subclass miscellaneous, rev
0x02) at pci0 dev 5 function 1 not configured
vendor Intel, unknown product 0x2f2a (class system subclass miscellaneous, rev
0x02) at pci0 dev 5 function 2 not configured
vendor Intel, unknown product 0x2f2c (class system subclass interrupt, rev
0x02) at pci0 dev 5 function 4 not configured
vendor Intel, unknown product 0x8d7c (class undefined unknown subclass 0x00,
rev 0x05) at pci0 dev 17 function 0 not configured
ahci0 at pci0 dev 17 function 4 vendor Intel, unknown product 0x8d62 rev 0x05:
msi, AHCI 1.3
scsibus0 at ahci0: 32
