Re: server crashing

[Al - Image Hosting Services <azick%zickswebventures.com@localhost>]

Hi,

On Mon, 22 Aug 2011, Greg Troxel wrote:
> I think you said the problem happened with rsync over NFS.  Two things:

Yes.

>  rsync can stress disks and power supplies

I would agree. Is there a better way to back things up?

>  I am suspicious of NFS.

I have NFSD running on one system and then I mounted /usr/web on the 
other. I then run rsync -auv --delete /usr/web/* /backup/web

The system running rsync works fine. The server running NFSD crashes.

The system running rsync is a 450 Mhz PowerPC running NetBSD 4 and the 
NFSD system is a 2.4 Ghz Core2Duo running NetBSD 5.1. Also, on NetBSD 4 
the server would start 4 nfsd processes, where on NetBSD 5.1 it only 
starts 1. I have to wonder if this isn't part of the issue.

> So I would recommend that you try rsync over ssh (with rsync installed
> on the machine with the destination disk).

I added bwlimit=512 and it seems to be working, but it is going to take a 
very long time to backup 600+ GB of data. Would ssh put other limitations 
on rsync?

> Also, I've found that wapbl on huge disks (2T) with small ram (512M) and
> full-speed writing to that fs can cause problems, or at least by problem
> seemed correlated with that.  But I also had problems with opencrypto
> (soekris net5501) and I'm not 100% sure what was wrong - just that I
> found a stable situation.

Both systems have 1GB of ram. The NFSD system has a 1TB Sata drive. Where 
as the other system has 3 scsi drives (320GB, 500GB, and 750GB).

Thanks,
Al