Re: Automating file xfer with NFS

On Wed, 24 Feb 2010, JK wrote:

My idea of an improved process would be to use NFS to establish a link to
the .txt file on the corporate server and submit the update process to batch
at a predetermined time. Assuming that we can address any firewall blockages
and CCSID issues, am I correct in my assumption that using NFS would pretty
much be a drop-in replacement for the manual email step? The existing CL/RPG
retrieves the data from an IFS link anyway and I'm thinking that NFS should
handle the actual transfer. What I don't know is:

1) How is Windows resolving the SMB link and how do I translate that
to NFS lingo

2) Although this will happen inside the corporate firewall, I need to
be mindful of security. I'm assuming that some of the iSeries NFS servers
need to be started but I'm not clear on which ones are necessary to resolve
the link to the .txt file at the corporate office. It shouldn't be necessary
to expose any of the iSeries folders.

3) Or maybe I should use FTP instead?

I think the first consideration is whether or not NFS would work at all in your environment. NFS is designed to be used by machines that "trust" each other. An NFS server will allow any machine to mount NFS shares whose IP address matches the restrictions in /etc/exports. NFS is a wonderful tool, but it isn't the most secure. That said, in my opinion, any environment that allows the SMB protocol is secure enough to allow NFS as well.

Another consideration is whether or not your corporate server can use NFS. Every UNIX or linux or BSD machine can, as can any System i made in the last 10 years or so. On windows I believe it requires an add-on, but I'm not sure from where.

If NFS will work for you, then it is pretty simple to set up and a breeze to use. On my linux system, I want all system to share a common /home directory. I have configured one machine to be the NFS server. In /etc/exports on that machine I have the following:

/home 10.100.47.0/255.255.255.0(rw,sync,no_root_squash,no_subtree_check)

This means that all hosts in the 10.100.47.0 subnet can mount /home. Once a machine mounts that directory, I can use that directory on that machine as if it were a local directory. In fact, the users have no idea that /home isn't on the local machine. The great thing about NFS is that it is completely transparent. No fooling around with drive letters or hostnames or silly network places.

James Rich

if you want to understand why that is, there are many good books on
the design of operating systems. please pass them along to redmond
when you're done reading them :)
- Paul Davis on ardour-dev