NFS needs a replacement
My KDE was not starting up today. I tried to diagnose what was going on, but got no meaningful output in any log.
In the end it turned out it was me powering down the fileserver while the laptop powered up. It had already mounted the NFS share I use for backups and I pulled the plug on it before KDE booted up. I do not know who was responsible, but KDE stalling on the bootup was not giving me any clue about that. Thing is, KDE is not the culprit. NFS simply freezes if you do that. So you have to wait for a never happening timeout before you can continue. Stupid concept.
I was a bit reluctant to run Samba on my private net, since it seemed such an overkill, well, the last drop has fallen.
I still wonder if such a condition is undetectable and not possible to resolve, though. I am sure not the first to be hit by this, so I doubt there is an easy solution.
Another day in the wonderful world of computers. I wonder if I grow old enough to not need to know how the computers work to work with them.
2 October 2005 at 11:05
man mount
soft This option allows the kernel to time out if the nfs server is not responding for some time. The time can be specified with timeo=time. This option might be useful if your nfs server sometimes doesn’t respond or will be rebooted while some process tries to get a file from the server. Usually
2 October 2005 at 11:13
I couldn’t agree more. NFS is the absolute worst, for almost everything but caching, at least as far as I can tell. Doing a simple scp over my lan nets me 18M/sec, with same files over NFSv3 or v4 is ~1M/sec. NFS has so many issues I couldn’t even get into them all.
BTW- in case you don’t already know, if you’re using linux ‘umount -l’ is your friend in this case.
2 October 2005 at 11:41
M G Berberich:
I totaly forgot that one. Thanks for the reminder.
Avuton Olrich:
NFS is much faster than SCP here. I knew how to get out of it after knowing whats going on, I just wondered why it takes forever to realize the server is gone.
Well, NFS4 will have a hard time to convince me :}
2 October 2005 at 12:54
NFS is horrid…but you’re lucky, 2.4.14 will include FUSE AND v9fs support
FUSE is a “filesystem in userspace” approach - there’re already a “sshfs” which allows you to “mount” a remote filesystem in your filesystem namespace (no root needed)
And there’s v9fs, the port of Plan9’s 9P protocol, which allows you to export things like devices (need to play music in a remote box? Skip all the arts/esd crap, just use v9fs and import the remote /dev or whatever)
2 October 2005 at 17:40
SFS — http://www.fs.net
The only network fs I’ve found that actually gives you useful feedback and error-msgs. Also you don’t have to mount individual shares and therefore circumvent the timeout problem
2 October 2005 at 17:42
NFS is pretty gnarly (as in gnarled)… but I have to say that working on many platforms, the Linux implementation is the absolute worst… so maybe don’t blame nfs so much as blame linux for its flaky implementation. I use NFS a lot of BSD for example, and while I frequently find it a headache, I didn’t know the meaning of pain until I started using NFS on (gentoo) linux…
2 October 2005 at 18:25
I think FUSE (http://fuse.sourceforge.net/) is an answer to such problems. Because FUSE allows userspace filesystems, ordinary users don’t need root access to mount/unmount network shares, and the chances of a network failure crashing the whole system are lower.
FUSE (in combination with KIO-FUSE http://kde.ground.cz/tiki-index.php?page=KIO+Fuse+Gateway) can give non-KDE apps access to network locations set up with KIO-slaves like fish:/, smb:/, ftp:/, and webdav:/. Unfortunately, some people have reported not being able to stream video and music over KIO-slaves, although I can’t confirm that because KIO-FUSE fails to compile on my computer
Another option is to use FUSE with KDE-independent filesystems like SSHFS (http://fuse.sourceforge.net/sshfs.html), SMB for FUSE (http://hannibal.lr-s.tudelft.nl/fusesmb/), SMBNetFS (http://smbnetfs.airm.net/), and FuseDav (http://0pointer.de/lennart/projects/fusedav/).
What I think is much needed is a GUI for mounting/unmounting FUSE network shares, something that can probably be achieved by KDE with KNetAttach.
2 October 2005 at 18:47
I’ve been getting some freeze problems too, recently. My home boxes are 2.6.13 and 2.6.12 kernels. I thought the problems were related to a new PCI-IDE card I’d installed, but since reading this post on PlanetKDE, I’ve realised that every time the freeze happens, I’m doing something with NFS.
I’m looking into alternatives now…
3 October 2005 at 19:58
I wish there were some easy way to casually share folders on Linux w/out any technical knowledge. NFS requires synchronized UIDs on both ends, and Samba is a nightmare to set up… I’ve frankly never gotten it quite right. Then there’s the KDE file-sharing panel applet, which is just plain weird. Where’s the user-friendly Linux analog to Samba?