(I found this post in the blog’s “drafts” area; it seems I wrote it back in April (hence the references to my 701 still running Eeebuntu), but for some reason the piece was never published. I reckon it could still be of use to someone, and I don’t like to waste things I’ve spent time writing, so here is a quick delve into the Planetoid’s very own “dead letter office”…)
One of the things I really like about our Synology DS110j NAS device—being a user of at least two Linux-based PCs around the house—is that it offers just about every option for sharing files over a network that you can think of: SMB (Windows), AFP (Mac), WebDAV, FTP, SCP (I think) and NFS, to name just the ones that came to my mind. Most network-attached storage devices just give you Windows file-sharing (and if you’re lucky, FTP)—as, well, all computers “speak” SMB, don’t they?—so it’s welcome to find a NAS box which speaks so many “languages”!
Having two PCs running Linux in our house—my Eee 701 (Eeebuntu v3) and a “nettop” (Ubuntu Maverick Meerkat)—it made sense to set up NFS file-sharing, so that the machines could access the storage on the Synology box.
To cut a long story short, I managed to get this all working (in retrospect, I don’t quite know how it did), and all was well for a while. Then, a few weeks ago, our old ADSL modem/wireless router died on us, and we replaced it with a BT Home Hub 3 (very nice, does the job well, etc.).
It was around this time that I noticed something: the nettop PC was no longer mounting the NFS shares. Either the mount request would just sit there for ages and do nothing, or I was getting the dreaded “nfs.mount: access denied” message. I pored over the settings on the PCs and the Synology; everything seemed to match up, and there were no firewalls I was aware of on either side, which could be getting in the way.
For a while, I was even suspecting the Home Hub—there is a firewall on the device, and I wondered if, somehow, it could be blocking the ports required for NFS. I couldn’t see why this would be necessary within a home network, but I couldn’t think of any other possibility, so I started querying Web forums, to no immediate avail.
Last night, I was re-checking the NFS exports settings on the Synology (for what felt like the umpteenth time), and noticed something that had always been there, but which I hadn’t paid attention to before. The settings window contains some suggestions for valid syntax for specifying the IP address range, which will be allowed to access the NFS shares. I had specified the IP address range in the format XXX.XXX.XXX.*, which I thought would mean “all machines on our home LAN”… but this format wasn’t in the suggestions list.
I noticed one of the “valid syntax” suggestions was XXX.XXX.XXX.0/24, which I seemed to recall means “all machines in that range”, so I entered this into one of the NFS exports, and tried mounting the share from the Eee. Almost instantly, it worked… which led me to wonder why the old setting worked before but then suddenly didn’t, but I’m not going to look a gift horse in the mouth 🙂