Niall O'Broin wrote ;
>> 1./ Has anyone who might have done similar got any tips, e.g. blocksize
>> to use, etc.
As it turned out, blocksize was the least of my worries !
>Use a blocksize to dd such that a block fits into an NFS block. You can set
>the block sizes for an NFS mount with the rsize,wsize options. From the man
> This will make your nfs connection much faster than
> with the default buffer size of 1024. (NFSv2 does
> not work with larger values of rsize and wsize.)
>Mind you, I just tried this, and I was getting damn near wirespeed (copying
>10M in < 1 second) when I mounted with defaults, and using
>rsize=8192,wsize=8192 made no noticeable difference, but I'd use them
>anyway. Better use a slightly smaller block size than that to dd, otherwise
>protocol overhead will cause each dd block to become two NFS blocks which is
>exactly what you're trying to avoid.
>> 2./ Will dd work over NFS (is an NFS mount a block device and if not are
>> there alternatives ) ?
>Yes, it will. An NFS mount is seen as a block device by the OS which can
>write files to it just like any other block device. As for alternatives - as
>it's going to take you two hours to copy 7G if you saturate a 100baseT
>connection, perhaps plugging in a spare disk temporarily might be a better
Server in question is a Proliant 1850R. I installed an ATA disk (no
spare scsi to hand) only to be told
by the Compaq BIOS that it doesn't support ATA disks ! Discovered
exactly how dusty a Proliant can get...
>option. Of course, by the time you do that, integrate it into the OS etc.
>etc. the NFS option is probably a lot simpler, and certainly will take less
>of your time.
>> 3./ I have a feeling the ilug BBC might be an alternative to an
>> installation cd ?
>Hmm - not sure if it has support out of the box for the Smart-2 RAID. I'm
>pretty sure it has support for whatever kind of smart RAID is on a DL-360,
>because I've used it on a couple of those (though I ultimately built a
>special CD, that was only to have the latest kernel and the latest Smart
>drivers - the original did work)
>> 5/ Storage medium will be cd-r. Any issues using split to create 10 650
>> MB files from one 7 gig file ?
>Split should be fine, but I know I'd be checking first :-) But what OS will
>your NFS server be running ? Linux up to 2.2 has a 2GB filesize limit,
>though I gather this has gone in 2.4.
This was a bit of a pain. I tried using RedHat 6.2 before I recieved
Niall's reply, and, of course,
dd exited after 2 Gig. Next try was SuSE 7.0, add kernel 2.4.1 sources,
A few errors about modules on boot but nothing serious. Unfortunately
the Kernel-based NFS server
was totally broken; "function not implemented" type errors when trying
to start NFS server.
Something I could have tried here but didn't was SUsE's patched 2.4.2
Installed Solaris8 on the basis that the 2 Gig limit was Linux-related.
Of course dd is still running from
a SuSE 6.2 install cd. Again dd exited after 2 Gig.
Became rather hassled. Server needs to be backed up in 4 hours as others
will be installing Linux on it today and they will probably blow away
# Decided to dd the disk in sections e.g. ;
dd if=/dev/ida/c0d0 of=/mnt/nfs/1184200 count=1184200 ;
dd if=/dev/ida/c0d0 of=/mnt/nfs/2368400 count=1182400 skip=1184200 ;
dd if=/dev/ida/c0d0 of=/mnt/nfs/3552600 count=1182400 skip=2368400 ;
etc etc until done.
This has the advantage of leaving me with files of cd-burning size in
I sincerely hope that there are no "off-by-one" errors with the above !
>> Andrew Kemmy, SAIR & GNU Linux Certified Professional (and general
>> dogsbody admin ;)
>What's the story with SAIR certification now ? Haven't they merged their
>efforts with LPI ? Where did you do the SAIR exams ?
As far as I know SAIR and LPI are still seperate. Both sets of exams can
be taken at any
authorised Sylvan Prometric testing centre (which B.I.C. are, and so
probably are a lot of
the other commercial training centres (SureSkills, etc)). Generally we
only run exams for people
who have taken courses with us, but we do make the occasional exception
Andrew Kemmy, A rather sleep-deprived SAIR & GNU Linux Certified
7 Exchange Place
IFSC Dublin 1.
00 3531 6702900
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