NFS problem -- solved.

John Clark jclark at
Thu May 3 20:59:58 UTC 2007

John Clark schrieb:
> I am copying a 'disk image' to an NFS mounted volume.
> I'm using:
> dd if=/dev/ad0 of=Disk.img
> After dd completes the number of blocks indicated is what the raw disk 
> device should
> be. However, when I look at the NFS mounted image, the file size is 
> anything but the
> 80 GB size it should be. 

I looked in to this, and what is happing, is this.

I'm booting a FreeBSD diskless node, to 'clone' the existing harddrive. 
The FreeBSD boot code
apparently mounts the root file system usin NFS V2, which has the 2.5 GB 
(or so) file
size limit, due to using only a signed 32 bit integer for file size. 
This was found in the 'pxe' boot

By executing an explicit 'mount' command with the '-3' option, I 
selected NFS V3, which
does not have this limitation, and was able to copy a previously 
captured 80 GB image onto
the harddrive. I'll check the other way around after I do an fsck on the 
resulting cloned drive.

John Clark.

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