On Mon, 2009-11-23 at 15:00 -0800, Rick Stevens wrote: > On 11/21/2009 10:41 AM, John Austin wrote: > > On Sat, 2009-11-21 at 11:11 -0700, Greg Woods wrote: > >> On Sat, 2009-11-21 at 10:09 +0000, John Austin wrote: > >> > >>> > >>> When copying a large file (2.7GB) from the server to the > >>> F12 m/c a complete freeze of the F12 machine occurs. > >> > >> > >> I haven't seen freezes, but I have seen corruption when trying to copy > >> large files (e.g. like a DVD iso image) via NFS. In fact, this happened > >> to me when I was trying to install an F12 virtual machine on my F11 box > >> (so I could try it out before deciding whether or not to bite the bullet > >> and upgrade the host OS). I copied over the DVD iso image, then tried to > >> install a VM from it, and it failed the media test. Sure enough, it also > >> failed the sha256sum test. Copying the same DVD iso file via scp instead > >> worked fine. I do not trust NFS for large files. > >> > >> --Greg > >> > >> > > > > Hi Greg > > > > That's interesting and very worrying - surely it can't/shouldn't happen! > > > > I have been using NFS for years for all types/sizes of files and > > never had a problem until the last couple of months. > > > > 1. The Centos/RHEL 5.3/5.4 kernel had a serious bug that has been fixed with the > > latest kernel update > > > > 2. Now this F12 problem > > > > Surely a very large worldwide community uses NFS ? > > > > OK the F12 case could be my finger trouble or even a hardware problem > > > > I will install F12 on a second machine and test again (against the same server) > > Can you verify that you run into the same issue if you run NFS over TCP > as opposed to NFS over UDP (it's an option in the mount command on the > client, use either "proto=tcp" or "proto=udp"). > > By default, the system queries the server and selects a protocol based > on what's being asked of it. See the "TRANSPORT METHODS" section of > "man nfs". > ---------------------------------------------------------------------- > - Rick Stevens, Systems Engineer ricks@xxxxxxxx - > - AIM/Skype: therps2 ICQ: 22643734 Yahoo: origrps2 - > - - > - The Theory of Rapitivity: E=MC Hammer - > - -- Glenn Marcus (via TopFive.com) - > ---------------------------------------------------------------------- Hi Rick Many thanks for the reply - you have found a work-around !! Just tested my machine with UDP and TCP This was using md5sum for about 10GB over the NFS mount 1. The default for F12/Centos5.4 appears to be TCP - which freezes 2. Forcing UDP gives NO errors for 10GB transfer 3. Forcing TCP gives a freeze Having briefly read the man pages this is the opposite of what I would expect and of what you suggest !! There must be a timing problem somewhere - Please see the other thread "Sky2 NIC Problem? - Was F12 NFS Failures" for other tests I have carried out Regards John -- fedora-list mailing list fedora-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list Guidelines: http://fedoraproject.org/wiki/Communicate/MailingListGuidelines
