Sorry for the message without body, im a little sleepy and hitted the wrong button... :p
Ok, I had this problem last night on one of our shiny Dell PowerEdge 2950s with RAID 10 and SAS disks. For no reason it started screaming "sd0: not queued: error 5" on the console, the server didnt crash (no core, no trace) but was in an unresponsive state, i couldnt log on or anything. I was wondering if this error could be a hardware problem (RAID card maybe?). The logs dont show anything notorious, there were no heavy IO at the time of the problem. I'm kind of clueless at what could have been the problem, a quick search showed some old messages with SCSI cards problems only. This is 4.0 Stable as shown below. dmesg follows: OpenBSD 4.0-stable (GENERIC) #1: Mon Nov 27 16:23:49 GMT 2006 [EMAIL PROTECTED]:/usr/src/sys/arch/i386/compile/GENERIC cpu0: Intel(R) Xeon(TM) CPU 3.00GHz ("GenuineIntel" 686-class) 3 GHz cpu0: FPU,V86,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CFLUS H,DS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,SBF,SSE3,MWAIT,DS-CPL,VMX,EST,CNXT-ID,C X16 cpu0: Enhanced SpeedStep disabled by BIOS real mem = 1072955392 (1047808K) avail mem = 970735616 (947984K) using 4256 buffers containing 53751808 bytes (52492K) of memory mainbus0 (root) bios0 at mainbus0: AT/286+(00) BIOS, date 06/21/06, BIOS32 rev. 0 @ 0xffe90, SMBIOS rev. 2.4 @ 0x3ffbc000 (62 entries) bios0: Dell Inc. PowerEdge 2950 pcibios0 at bios0: rev 2.1 @ 0xf0000/0x10000 pcibios0: PCI IRQ Routing Table rev 1.0 @ 0xfade0/384 (22 entries) pcibios0: PCI Interrupt Router at 000:31:0 ("Intel 6321ESB LPC" rev 0x00) pcibios0: PCI bus #16 is the last bus bios0: ROM list: 0xc0000/0x9000! 0xc9000/0x1000 0xca000/0x1800 0xcb800/0x5200 0xec000/0x4000! ipmi0 at mainbus0: version 2.0 interface KCS iobase 0xca8/8 spacing 4 cpu0 at mainbus0 pci0 at mainbus0 bus 0: configuration mode 1 (no bios) pchb0 at pci0 dev 0 function 0 "Intel 5000X Host" rev 0x12 ppb0 at pci0 dev 2 function 0 "Intel 5000 PCIE" rev 0x12 pci1 at ppb0 bus 6 ppb1 at pci1 dev 0 function 0 "Intel 6321ESB PCIE" rev 0x01 pci2 at ppb1 bus 7 ppb2 at pci2 dev 0 function 0 "Intel 6321ESB PCIE" rev 0x01 pci3 at ppb2 bus 8 ppb3 at pci3 dev 0 function 0 "ServerWorks PCIE-PCIX" rev 0xc2 pci4 at ppb3 bus 9 bnx0 at pci4 dev 0 function 0 "Broadcom BCM5708" rev 0x11: irq 5, address 00:18:8b:72:c0:fd brgphy0 at bnx0 phy 1: BCM5708C 10/100/1000baseT PHY, rev. 5 ppb4 at pci2 dev 1 function 0 "Intel 6321ESB PCIE" rev 0x01 pci5 at ppb4 bus 10 ppb5 at pci1 dev 0 function 3 "Intel 6321ESB PCIE-PCIX" rev 0x01 pci6 at ppb5 bus 11 ppb6 at pci0 dev 3 function 0 "Intel 5000 PCIE" rev 0x12 pci7 at ppb6 bus 1 ppb7 at pci7 dev 0 function 0 "Intel IOP333 PCIE-PCIX" rev 0x00 pci8 at ppb7 bus 2 mfi0 at pci8 dev 14 function 0 "Dell PERC 5" rev 0x00: irq 6 mfi0: logical drives 1, version 5.0.1-0030, 256MB RAM scsibus0 at mfi0: 1 targets sd0 at scsibus0 targ 0 lun 0: <DELL, PERC 5/i, 1.00> SCSI3 0/direct fixed sd0: 278784MB, 278784 cyl, 64 head, 32 sec, 512 bytes/sec, 570949632 sec total ppb8 at pci7 dev 0 function 2 "Intel IOP333 PCIE-PCIX" rev 0x00 pci9 at ppb8 bus 3 ppb9 at pci0 dev 4 function 0 "Intel 5000 PCIE" rev 0x12 pci10 at ppb9 bus 12 ppb10 at pci0 dev 5 function 0 "Intel 5000 PCIE" rev 0x12 pci11 at ppb10 bus 13 ppb11 at pci0 dev 6 function 0 "Intel 5000 PCIE" rev 0x12 pci12 at ppb11 bus 14 ppb12 at pci0 dev 7 function 0 "Intel 5000 PCIE" rev 0x12 pci13 at ppb12 bus 15 pchb1 at pci0 dev 16 function 0 "Intel 5000 Error Reporting" rev 0x12 pchb2 at pci0 dev 16 function 1 "Intel 5000 Error Reporting" rev 0x12 pchb3 at pci0 dev 16 function 2 "Intel 5000 Error Reporting" rev 0x12 pchb4 at pci0 dev 17 function 0 "Intel 5000 Reserved" rev 0x12 pchb5 at pci0 dev 19 function 0 "Intel 5000 Reserved" rev 0x12 pchb6 at pci0 dev 21 function 0 "Intel 5000 FBD" rev 0x12 pchb7 at pci0 dev 22 function 0 "Intel 5000 FBD" rev 0x12 ppb13 at pci0 dev 28 function 0 "Intel 6321ESB PCIE" rev 0x09 pci14 at ppb13 bus 4 ppb14 at pci14 dev 0 function 0 "ServerWorks PCIE-PCIX" rev 0xc2 pci15 at ppb14 bus 5 bnx1 at pci15 dev 0 function 0 "Broadcom BCM5708" rev 0x11: irq 5, address 00:18:8b:72:c0:fb brgphy1 at bnx1 phy 1: BCM5708C 10/100/1000baseT PHY, rev. 5 uhci0 at pci0 dev 29 function 0 "Intel 6321ESB USB" rev 0x09: irq 11 usb0 at uhci0: USB revision 1.0 uhub0 at usb0 uhub0: Intel UHCI root hub, rev 1.00/1.00, addr 1 uhub0: 2 ports with 2 removable, self powered uhci1 at pci0 dev 29 function 1 "Intel 6321ESB USB" rev 0x09: irq 10 usb1 at uhci1: USB revision 1.0 uhub1 at usb1 uhub1: Intel UHCI root hub, rev 1.00/1.00, addr 1 uhub1: 2 ports with 2 removable, self powered uhci2 at pci0 dev 29 function 2 "Intel 6321ESB USB" rev 0x09: irq 11 usb2 at uhci2: USB revision 1.0 uhub2 at usb2 uhub2: Intel UHCI root hub, rev 1.00/1.00, addr 1 uhub2: 2 ports with 2 removable, self powered ehci0 at pci0 dev 29 function 7 "Intel 6321ESB USB" rev 0x09: irq 11 usb3 at ehci0: USB revision 2.0 uhub3 at usb3 uhub3: Intel EHCI root hub, rev 2.00/1.00, addr 1 uhub3: 6 ports with 6 removable, self powered ppb15 at pci0 dev 30 function 0 "Intel 82801BA AGP" rev 0xd9 pci16 at ppb15 bus 16 vga1 at pci16 dev 13 function 0 "ATI ES1000" rev 0x02 wsdisplay0 at vga1 mux 1: console (80x25, vt100 emulation) wsdisplay0: screen 1-5 added (80x25, vt100 emulation) ichpcib0 at pci0 dev 31 function 0 "Intel 6321ESB LPC" rev 0x09: PM disabled pciide0 at pci0 dev 31 function 1 "Intel 6321ESB IDE" rev 0x09: DMA, channel 0 configured to compatibility, channel 1 configured to compatibility atapiscsi0 at pciide0 channel 0 drive 0 scsibus1 at atapiscsi0: 2 targets cd0 at scsibus1 targ 0 lun 0: <HL-DT-ST, CD-ROM GCR-8240N, 1.10> SCSI0 5/cdrom removable cd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 2 pciide0: channel 1 ignored (disabled) isa0 at ichpcib0 isadma0 at isa0 pckbc0 at isa0 port 0x60/5 pckbd0 at pckbc0 (kbd slot) pckbc0: using irq 1 for kbd slot wskbd0 at pckbd0: console keyboard, using wsdisplay0 pcppi0 at isa0 port 0x61 midi0 at pcppi0: <PC speaker> spkr0 at pcppi0 npx0 at isa0 port 0xf0/16: reported by CPUID; using exception 16 pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo biomask ffc5 netmask ffe5 ttymask ffe7 pctr: user-level cycle counter enabled uhub4 at uhub3 port 5 uhub4: Cypress Semiconductor USB2 Hub, rev 2.00/0.0b, addr 2 uhub4: 4 ports with 4 removable, self powered, multiple transaction translators uhidev0 at uhub1 port 1 configuration 1 interface 0 uhidev0: CHESEN PS2 to USB Converter, rev 1.10/0.10, addr 2, iclass 3/1 ukbd0 at uhidev0: 8 modifier keys, 6 key codes wskbd1 at ukbd0 mux 1 wskbd1: connecting to wsdisplay0 uhidev1 at uhub1 port 1 configuration 1 interface 1 uhidev1: CHESEN PS2 to USB Converter, rev 1.10/0.10, addr 2, iclass 3/1 uhidev1: 3 report ids ums0 at uhidev1 reportid 1: 5 buttons and Z dir. wsmouse0 at ums0 mux 0 uhid0 at uhidev1 reportid 2: input=1, output=0, feature=0 uhid1 at uhidev1 reportid 3: input=3, output=0, feature=0 dkcsum: sd0 matches BIOS drive 0x80 root on sd0a rootdev=0x400 rrootdev=0xd00 rawdev=0xd02 WARNING: / was not properly unmounted