Re: Limit of 256 NFS Mounted Filesystems

Fri, 4 Dec 1998 17:12:02 +0100 (MET)

On Fri, 4 Dec 1998, Richard Kaszeta wrote:

> Unfortunately, I've discovered that 256 is as high as one can reasonly
> put this limit, even with the 2.1.x kernel, as each nfs (or other
> 'nodev' type of mount) requires a device of major number 0 and a
> different minor number, so there can only be 255 nodev filesystems at
> any given time.

Yes. My understanding is that this should be fixed by the bigger dev_t in
the 2.3 kernel series (but not before, because there is a lot of issues
with this because dev_t is part of the exported kernel API)

> Anyone have ideas for workarounds? I have a *huge* amount of storage
> here for each user, which is why I starting using autofs to start
> with---it was the only efficient way of serving home directories
> (which are spread over a couple dozen servers and devices anyways, so
> most alternative schemes still would run into some of these limits).

dunno. perhaps you could try to mount each of these devices in their
entirety, and not each home dir separately. But yes, this is a very
serious limitation.

> We need to fix this if we are to claim that linux is a serious candidate
> for server use.

We will. but probably not before 2.3 :-(

Michel "Walken" LESPINASSE - Development Engineer at Wind River Systems
Microsoft is not the answer. Microsoft is the question. The answer is no.

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