topic how to manual timeout cache when mounted nfs export on vms in Operating System - OpenVMS

how to manual timeout cache when mounted nfs export on vms

caleb baker — Wed, 25 Nov 2009 06:35:46 GMT

Hi all

I have mounted an nfs device on VMS from linux and am writing to a file on linux and then need to access that file on vms but the vms nfs client cannot see the file yet.

Is there a way to tell the vms nfs client that it shouldn't use the cached version?

i've found /cache_timeout option when mounting the device but would prefer a way to do it manually as decreasing the cache timeout value will increase network usage and I still wouldn't be able to guarentee that the file will be there.

I've tried running type on the file to get vms to prod the nfs server to get the file with mixed results.

Thanks
Caleb Baker

Re: how to manual timeout cache when mounted nfs export on vms

Hoff — Wed, 25 Nov 2009 15:34:17 GMT

Sure; it's called sftp, scp, http get/post, ftp, or...

This isn't really an OpenVMS question, FWIW. Substantial caching is inherent in nfs clients and servers and particularly prior to V4 and with versions prior to 3 lacking even weak coherence options; if you don't cache extensively, then nfs performance craters.

Some NFS caching Background:
http://www.unixcoding.org/NFSCoding

Gonzo NFS background:

_NFS Illustrated_, by Brent Callaghan.

NFS (and particularly the older, stateless versions) is not suited to rapid turn-around file-sharing operations.