Dear Gurus,
I am trying to make backups of various machines on another
machine (backup_host).
Can someone explain please why this fails:
backup_host# rsh rem_host /sbin/vdump -0 -b 64 -f - /usr | dd of=/dev/nrmt0h obs=8192k conv=sync
AND these fail in the same way ...
rem_host# vdump -0 -b 64 -f - /usr/users | rsh backup_host dd of=/dev/nrmt0h obs=8192k conv=sync
backup_host# rsh rem_host /sbin/vdump -0 -b 64 -f - /usr >/tmp/rem_host.tst; cat /tmp/rem_host.tst | dd of=/dev/nrmt0h obs=8192k conv=sync
(Though restoring from /tmp/rem_host.tst works.)
They produce the following result:
backup_host# vrestore -f /dev/nrmt0h -i
vrestore: unable to restore block <2>; corrupt block
BLOCK HEADER
block size : 1634235432
flags : <files><quotas>
volume set : 29296
volume sets: 28201
volume num : 25896
block num : 28201
header CRC : 0x6328
block CRC : 0x6e29
xor blocks : 25896
xor blk num: 28201
id : Fri May 9 02:36:56 2031
version : )f(the)h(sub-)h(and)e(sup)n(erscript)
g(symb)n(ols.)29 b FL(W)l(e)18 b(see)164 436 y(no)o(w)f(no)o(w)h(that)g
(our)f(initial)f(examples)f(w)o(ork)o(ed)i(b)o(y)f(considering)h(a)h
(single)e(c)o(haracter)164 496 y(to)h(b)q(e)f(a)h(group)g(b)o(y)f
(itself.)k(Here)15 b(are)h(some)f(examples:)455 614 y
Fr(T)m(yp)n(e)754 b(T)m(o)14 b(pr)n(o)n(duc)n(e)455 679
y FA($a^2b^3$)663 b Fk(a)1316 664 y Fy(2)1334 679 y Fk(b)1352
664 y Fy(3)455 744 y FA($2^{21}$)g Fz(2)1315 729 y Fy(21)455
809 y FA($2^21$)707 b Fz(2)1315 793 y Fy(2)1333 809 y
... etc ...
Fy(=1)1587 606 y Fk(a)1609 612 y Fj(i)189 671 y FA($\\int_a^b)h(f$)1481
637 y FG(R)1509 648 y Fj(b)1500 686 y(a)1532 671 y Fk(f)189
736 y FA($\\oint_{\\cal)f^B
0 0x61687428 0x28682974 0x6e297270 0x6e296528
4 0x6e296328 0x6e296528 0x73656428 0x74286629
8 0x68296568 0x62757328 0x2868292d 0x29646e61
12 0x75732865 0x286e2970 0x63737265 0x74706972
16 0x28670a29 0x626d7973 0x6f286e29 0x292e736c
20 0x62203932 0x284c4620 0x286c2957 0x38312965
24 0x73286220 0x31296565 0x34203436 0x79203633
28 0x296f6e28 0x2977286f 0x6f6e2866 0x77286f29
32 0x74286829 0x29746168 0x6f280a67 0x66297275
36 0x696e6928 0x6c616974 0x65286629 0x706d6178
40 0x2973656c 0x29772866 0x726f286f 0x286f296b
44 0x69296465 0x6f296228 0x66297928 0x6e6f6328
48 0x65646973 0x676e6972 0x61286829 0x280a6829
52 0x676e6973 0x6529656c 0x6f296328 0x72616828
56 0x65746361 0x36312972 0x39342034 0x28792036
60 0x68296f74 0x71296228 0x66296528 0x68296128
vrestore: unable to restore block <5>; corrupt block
BLOCK HEADER
block size : 841508393
flags : <quotas>
volume set : 26153
volume sets: 16680
volume num : 29557
block num : 29300
header CRC : 0x6c61
block CRC : 0x6169
xor blocks : 12329
xor blk num: 12832
id : Mon Feb 16 08:16:36 1987
version : y Fm(2)43 2424
y Fk(Departmen)o(t)j(of)i(Ph)o(ysics)e(and)h(Astronom)o(y)l(,)g
(McMaster)g(Univ)o(ersit)o(y)l(,)g(Hamilton,)h(On)o(tario,)0
2507 y(L8S4M1,)16 b(Canada)0 2629 y Fm(3)43 2647 y Fk(Curren)o(t)i
(address:)27 b(F)l(acult)o(y)20 b(of)g(Mathematics,)g(Op)q(en)g(Univ)o
(ersit)o(y)l(,)g(Milton)f(Keynes,)i(MK7)0 2730 y(6AA,)c(United)g
(Kingdom)914 2859 y(1)p eop
%%Page: 2 2
2 1 bop 80 50 a Fk(In)18 b(the)h(harmonic)e(appro)o(ximation)g(the)i
... and again ...
56 0x6e657272 0x74286f29 0x280a6929 0x72646461
60 0x3a737365 0x20373229 0x29462862 0x6361286c
vrestore: unable to restore block <6>; corrupt block
BLOCK HEADER
block size : 33554442
flags : <compressed><dirs>
volume set : 2827
volume sets: 2569
volume num : 2571
block num : 2826
header CRC : 0x0908
block CRC : 0x0609
xor blocks : 2312
xor blk num: 2056
id : Sat Oct 19 14:46:00 1974
version : ^G ^E^^^G^F^G ^^^^G^^^^^H
^G^^^F^^H ^^F
^K
^I
^K ^I^L^K^M ^G^^E^E
... and so on.
Yet this works:
rem_host# vdump -0 -b 64 -f - /usr/users | rsh backup_host cat - '>' /tmp/rem_host.tst
backup_host# vrestore -f /tmp/rem_host.tst -i
As does this:
backup_host# vdump -0 -b 64 -f - /fileset
...
backup_host# vrestore ...
backup_host# rsh rem_host /sbin/vdump -0 -b 64 -f - /usr >
/tmp/rem_host.tst; cat /tmp/rem_host.tst | dd of=/dev/nrmt0h
obs=8192k conv=sync
I have tried changing and matching block-sizes on the dd and vdump.
Have also tried different machines in place of rem_host.
backup_host is an ES40 with 4 CPUs and 6G RAM and 4.0f, rem_host is an old
Digital workstation running somthing like 4.0a
I have NOT yet tried with various other remote machines running
irix, linux and solaris, which I also need to get working... :(
Obviously I'd like to keep using large values for the dd obs to get
the tape to finish writing sometime this century.
My guess is that it's a dd problem. But can it be fixed or dealt
with??
Any suggestions or knowledge available would be greatly appreciated.
Thanks
Glen
--
Glen Davison glen_at_maths.unsw.edu.au
Computer System Administrator phone: +61 2 9385 7018
Maths, UNSW fax: +61 2 9385 7123
Received on Mon Aug 14 2000 - 02:58:43 NZST