I have same problem on same class machine, here is dmesg from failing boot
(via serial console):
--------------------
Copyright (c) 1992-2003 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD 4.8-RELEASE-p7 #0: Sat Sep 20 17:07:38 EEST 2003
root:/space/usr/obj/space/usr/src/sys/MYKERN
Timecounter "i8254" frequency 1193182 Hz
Timecounter "TSC" frequency 199447955 Hz
CPU: Pentium Pro (199.45-MHz 686-class CPU)
Origin = "GenuineIntel" Id = 0x619 Stepping = 9
Features=0xf9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV>
real memory = 134217728 (131072K bytes)
avail memory = 125222912 (122288K bytes)
Preloaded elf kernel "kernel" at 0xc0548000.
Pentium Pro MTRR support enabled
md0: Malloc disk
npx0: <math processor> on motherboard
npx0: INT 16 interface
pcib0: <Host to PCI bridge> on motherboard
pci0: <PCI bus> on pcib0
Correcting Natoma config for non-SMP
pcib1: <IBM 82351 PCI-PCI bridge> at device 13.0 on pci0
pci1: <PCI bus> on pcib1
pci1: <Cirrus Logic GD5430 SVGA controller> at 6.0
tl0: <Compaq Netelligent 10/100 Proliant> port 0x6480-0x648f mem
0x40001500-0x4000150f irq 5 at device 7.0 on pci1
tl0: Ethernet address: 00:08:c7:78:08:57
miibus0: <MII bus> on tl0
nsphy0: <DP83840 10/100 media interface> on miibus0
nsphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
tlphy0: <ThunderLAN 10baseT media interface> on miibus0
tlphy0: 10base2/BNC, 10base5/AUI
sym0: <875> port 0x6000-0x60ff mem
0x40000000-0x40000fff,0x40001400-0x400014ff irq 11 at device 9.0 on pci1
sym0: No NVRAM, ID 7, Fast-20, SE, parity checking
dc0: <Intel 21143 10/100BaseTX> port 0x6400-0x647f mem
0x40001000-0x400013ff
irq 9 at device 10.0 on pci1
dc0: Ethernet address: 00:40:f4:23:02:65
miibus1: <MII bus> on dc0
ukphy0: <Generic IEEE 802.3u media interface> on miibus1
ukphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
pci1: <unknown card> (vendor=0x11d4, dev=0x1805) at 13.0 irq 15
isab0: <PCI to EISA bridge (vendor=0e11 device=0001)> at device 20.0 on
pci0
eisa0: <EISA bus> on isab0
mainboard0: <CPQ0551 (System Board)> on eisa0 slot 0
isa0: <ISA bus> on isab0
orm0: <Option ROMs> at iomem
0xc0000-0xc7fff,0xe8000-0xedfff,0xee000-0xeffff
on isa0
ep0: <3Com 3C509-Combo EtherLink III> at port 0x320-0x32f irq 10 on isa0
ep0: Ethernet address 00:a0:24:1d:1a:50
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
ata0 at port 0x1f0-0x1f7,0x3f6 irq 14 on isa0
ata1 at port 0x170-0x177,0x376 irq 15 on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x100>
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 16550A, console
sio1 at port 0x2f8-0x2ff irq 3 on isa0
sio1: type 16550A
ppc0: <Parallel port> at port 0x3bc-0x3bf irq 7 on isa0
ppc0: Generic chipset (NIBBLE-only) in COMPATIBLE mode
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
ipfw2 initialized, divert enabled, rule-based forwarding enabled, default to
accept, logging limited to 100 packets/entry by default
IPv6 packet filtering initialized, default to accept, logging limited to 100
packets/entry
DUMMYNET initialized (011031)
IPsec: Initialized Security Association Processing.
IP Filter: v3.4.31 initialized. Default = block all, Logging = enabled
acd0: CDROM <CD-ROM CDU571-Q> at ata0-master BIOSPIO
sa0 at sym0 bus 0 target 6 lun 0
sa0: <HP C1533A A907> Removable Sequential Access SCSI-2 device
sa0: 10.000MB/s transfers (10.000MHz, offset 16)
Mounting root from ufs:/dev/da0s1a
no such device 'da'
setrootbyname failed
ffs_mountroot: can't find rootvp
Root mount failed: 6
--------------------
also, i added working 4.7-p10 kernel dmesg:
----------------------
Copyright (c) 1992-2002 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
The Regents of the University of California. All rights reserved.
FreeBSD 4.7-RELEASE-p10 #0: Sun May 11 06:18:40 EEST 2003
root:/space/usr/obj/space/usr/src/sys/MYKERN
Timecounter "i8254" frequency 1193182 Hz
Timecounter "TSC" frequency 199448159 Hz
CPU: Pentium Pro (199.45-MHz 686-class CPU)
Origin = "GenuineIntel" Id = 0x619 Stepping = 9
Features=0xf9ff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,SEP,MTRR,PGE,MCA,CMOV>
real memory = 134217728 (131072K bytes)
avail memory = 125251584 (122316K bytes)
Preloaded elf kernel "kernel.work" at 0xc0541000.
Pentium Pro MTRR support enabled
md0: Malloc disk
npx0: <math processor> on motherboard
npx0: INT 16 interface
pcib0: <Host to PCI bridge> on motherboard
pci0: <PCI bus> on pcib0
pcib1: <IBM 82351 PCI-PCI bridge> at device 13.0 on pci0
pci1: <PCI bus> on pcib1
pci1: <Cirrus Logic GD5430 SVGA controller> at 6.0
tl0: <Compaq Netelligent 10/100 Proliant> port 0x6480-0x648f mem
0x40001500-0x4000150f irq 5 at device 7.0 on pci1
tl0: Ethernet address: 00:08:c7:78:08:57
miibus0: <MII bus> on tl0
nsphy0: <DP83840 10/100 media interface> on miibus0
nsphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
tlphy0: <ThunderLAN 10baseT media interface> on miibus0
tlphy0: 10base2/BNC, 10base5/AUI
sym0: <875> port 0x6000-0x60ff mem
0x40000000-0x40000fff,0x40001400-0x400014ff irq 11 at device 9.0 on pci1
sym0: No NVRAM, ID 7, Fast-20, SE, parity checking
dc0: <Intel 21143 10/100BaseTX> port 0x6400-0x647f mem
0x40001000-0x400013ff
irq 9 at device 10.0 on pci1
dc0: Ethernet address: 00:40:f4:23:02:65
miibus1: <MII bus> on dc0
ukphy0: <Generic IEEE 802.3u media interface> on miibus1
ukphy0: 10baseT, 10baseT-FDX, 100baseTX, 100baseTX-FDX, auto
pci1: <unknown card> (vendor=0x11d4, dev=0x1805) at 13.0 irq 15
isab0: <PCI to EISA bridge (vendor=0e11 device=0001)> at device 20.0 on
pci0
eisa0: <EISA bus> on isab0
mainboard0: <CPQ0551 (System Board)> on eisa0 slot 0
isa0: <ISA bus> on isab0
orm0: <Option ROMs> at iomem
0xc0000-0xc7fff,0xe8000-0xedfff,0xee000-0xeffff
on isa0
ep0: <3Com 3C509-Combo EtherLink III> at port 0x320-0x32f irq 10 on isa0
ep0: Ethernet address 00:a0:24:1d:1a:50
fdc0: <NEC 72065B or clone> at port 0x3f0-0x3f5,0x3f7 irq 6 drq 2 on isa0
fdc0: FIFO enabled, 8 bytes threshold
fd0: <1440-KB 3.5" drive> on fdc0 drive 0
ata0 at port 0x1f0-0x1f7,0x3f6 irq 14 on isa0
ata1 at port 0x170-0x177,0x376 irq 15 on isa0
atkbdc0: <Keyboard controller (i8042)> at port 0x60,0x64 on isa0
atkbd0: <AT Keyboard> flags 0x1 irq 1 on atkbdc0
kbd0 at atkbd0
vga0: <Generic ISA VGA> at port 0x3c0-0x3df iomem 0xa0000-0xbffff on isa0
sc0: <System console> at flags 0x100 on isa0
sc0: VGA <16 virtual consoles, flags=0x100>
sio0 at port 0x3f8-0x3ff irq 4 flags 0x10 on isa0
sio0: type 16550A, console
sio1 at port 0x2f8-0x2ff irq 3 on isa0
sio1: type 16550A
ppc0: <Parallel port> at port 0x3bc-0x3bf irq 7 on isa0
ppc0: Generic chipset (NIBBLE-only) in COMPATIBLE mode
plip0: <PLIP network interface> on ppbus0
lpt0: <Printer> on ppbus0
lpt0: Interrupt-driven port
ppi0: <Parallel I/O> on ppbus0
ipfw2 initialized, divert enabled, rule-based forwarding enabled, default to
accept, logging limited to 100 packets/entry by default
IPv6 packet filtering initialized, default to accept, logging limited to 100
packets/entry
DUMMYNET initialized (011031)
IPsec: Initialized Security Association Processing.
IP Filter: v3.4.29 initialized. Default = block all, Logging = enabled
acd0: CDROM <CD-ROM CDU571-Q> at ata0-master BIOSPIO
sa0 at sym0 bus 0 target 6 lun 0
sa0: <HP C1533A A907> Removable Sequential Access SCSI-2 device
sa0: 10.000MB/s transfers (10.000MHz, offset 16)
da0 at sym0 bus 0 target 0 lun 0
da0: <COMPAQ WDE4360S 1.52> Fixed Direct Access SCSI-2 device
da0: 40.000MB/s transfers (20.000MHz, offset 15, 16bit), Tagged Queueing
Enabled
da0: 4094MB (8386000 512 byte sectors: 255H 63S/T 522C)
da1 at sym0 bus 0 target 1 lun 0
da1: <COMPAQ WDE4360S 1.52> Fixed Direct Access SCSI-2 device
da1: 40.000MB/s transfers (20.000MHz, offset 15, 16bit), Tagged Queueing
Enabled
da1: 4094MB (8386000 512 byte sectors: 255H 63S/T 522C)
Mounting root from ufs:/dev/da0s1a
Enter full pathname of shell or RETURN for /bin/sh:
------------------------
diff of them seems like normal, i found no intresting differences
i have no idea what i do next, i want to upgrade my system, cause there are
security updates (thats not meaning i have old sshd &bind and others, they
are installed via ports)
i dont think that developers removed that from source, but, thats weird,
very weird
>
>Can you post a full dmesg of the failing boot? You can get this by
>using a serial console (see the Handbook). If you have to copy it by
>hand, the critical lines are the sym0 and da0 lines (or any errors
>near where those lines should be). How does it differ from the
>dmesg when booting a good kernel?
>
>Peter