a black cat in a dark room? -- problems

["Denis A. Doroshenko" <cyxob_(_at_)_isl_(_dot_)_vtu_(_dot_)_lt>]

Hi!

One my station behaves very strange:
after ~10-12 hours of work it crashes... coming to work at morning i saw
something like that
2.1:
-----------------------------------------------------------------------------
OpenBSD/i386 (desert) (ttyC0)

login: vm_fault (0xf02e3000, f2539000,3,0) -> 1
kernel: page fault trap, code = 0
Stopped at _bzero+0x4f: movl %eax, 0x38(%edi)
ddb>
-----------------------------------------------------------------------------


2.2: the same sympthoms (10-12 hours and...):
-----------------------------------------------------------------------------
Dec 18: 10:00:01 desert sendmail[29542] NOQUEUE: SYSERR(UID0): /etc/sendmail.cf:
 line 0: cannot open: No such file or directory

login: root
           Dec 18 10:42:36 desert login: /etc/spwd.db: No such file or directory
Password:
Login incorrect
login:
------------------------------------------------------------------------------

I know what exactly happens to 2.2 (it happened one time when i was
compiling the buildind the system): it strangely loses /etc directory
(ONLY /etc!) and you may figure what the work without /etc...
it looks like that:

------------------------------------------------------------------------------
root_(_at_)_desert/ # ls
.cshrc    arc       bsd       home      root      sys       var
.profile  bin       dev       mnt       sbin      tmp
altroot   boot      etc       obsd      stand     usr
root_(_at_)_desert/ # ls -l
total 6072
-rw-r--r--   2 root  wheel      687 Nov  2 10:30 .cshrc
-rw-r--r--   2 root  wheel      210 Dec 13 10:38 .profile
drwxr-xr-x   2 root  wheel      512 Nov  2 10:30 altroot
drwxr-xr-x   2 root  wheel      512 Dec 11 17:05 arc
drwxr-xr-x   2 root  wheel     1024 Nov  2 10:36 bin
-r-xr-xr-x   1 root  wheel    40960 Dec 12 09:22 boot
-rw-r--r--   1 root  wheel  1237855 Dec 12 18:55 bsd
drwxr-xr-x   4 root  wheel    12288 Dec 18 12:47 dev
drwxr-xr-x   6 root  wheel      512 Dec 13 12:32 home
drwxr-xr-x   2 root  wheel      512 Nov  2 10:30 mnt
-rw-r--r--   1 root  wheel  1773522 Nov  2 12:09 obsd
drwxr-xr-x   4 root  wheel      512 Dec 16 16:12 root
drwxr-xr-x   2 root  wheel     1536 Nov  2 10:55 sbin
drwxr-xr-x   2 root  wheel      512 Nov  2 10:30 stand
lrwxr-xr-x   1 root  wheel       11 Dec 11 23:59 sys -> usr/src/sys
drwxrwxrwt   2 root  wheel      512 Dec 18 12:47 tmp
drwxr-xr-x  15 root  bin        512 Nov 18 04:14 usr
drwxr-xr-x  19 root  bin        512 Nov 18 04:15 var
root_(_at_)_desert/ #
------------------------------------------------------------------------------

look ls shows etc presenting in /, but ls -lA doesn't. I don't know if
it's software or hardware problem, but here's dmesg

------------------------------------------------------------------------------
root_(_at_)_desert/root # dmesg
OpenBSD 2.2 (DESERT) #0: Fri Dec 12 18:55:27 EET 1997
    cyxob_(_at_)_desert:/usr/src/sys/arch/i386/compile/DESERT
CPU: Cx486DLC (CyrixMC UMC  486-class CPU)
WARNING: CYRIX 486DLC CACHE UNCHANGED.
BIOS mem  = 655360 conventional, 15728640 extended
real mem  = 16384000
avail mem = 13381632
using 225 buffers containing 921600 bytes of memory
mainbus0 (root)
bios0 at mainbus0: AT/286+(00) BIOS, date 07/25/94
bios0: diskinfo 0xf02eb00c cksumlen 1 memmap 0xf02eb108
isa0 at mainbus0
ep0 at isa0 port 0x300-0x30f irq 10: unknown 3Com Ethernet card: f074afb0
ep0: address 00:a0:24:7e:47:66, utp/aui/bnc (default bnc)
lpt0 at isa0 port 0x378-0x37b irq 7
isadma0 at isa0
wdc0 at isa0 port 0x1f0-0x1f7 irq 14
wd0 at wdc0 drive 0: <QUANTUM LPS340A>
wd0: 325MB, 1011 cyl, 15 head, 44 sec, 512 bytes/sec (98KB cache)
wd0: using 8-sector 16-bit pio transfers, chs addressing
wd1 at wdc0 drive 1: <WDC AC2420F>
wd1: 405MB, 989 cyl, 15 head, 56 sec, 512 bytes/sec (64KB cache)
wd1: using 16-sector 16-bit pio transfers, chs addressing
pccom0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
pccom1 at isa0 port 0x2f8-0x2ff irq 3: ns8250 or ns16450, no fifo
vt0 at isa0 port 0x60-0x6f irq 1: tvga 9100, 80 col, color, 2 scr,
mf2-kbd, [R3.32]
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB 80 cyl, 2 head, 18 sec
biomask 4040 netmask 4440 ttymask 44c2
dkcsum: wd0 matched BIOS disk 80
dkcsum: wd1 matched BIOS disk 81
rootdev=0x0 rrootdev=0x300 rawdev=0x302
----------------------------------------------------------------------------

Eh, CPU type seems horribly [FreeBSD kernel detects it as UMC U5, BIOS
calls it UMC U5 486SX33-S] but it's performance for 10% bigger than AMD 486DX40.
Other dmesg's strings seem don't need comments.

May be some one had something like this?

CYXOB