Re: It's back! (Re: [REGRESSION] NFS is creating a hidden port (left over from xs_bind() ))

[Steven Rostedt]

On Thu, 30 Jun 2016 18:30:42 +0000
Trond Myklebust <trondmy@xxxxxxxxxxxxxxx> wrote:


> Wait. So the NFS mount is still active, itâs just that the socket
> disconnected due to no traffic? That should be OK. Granted that the
> port canât be reused by another process, but you really donât want
> that: what if there are no other ports available and you start
> writing to a file on the NFS partition?

What would cause the port to be connected to a socket again? I copied a
large file to the nfs mount, and the hidden port is still there?

Remember, this wasn't always the case, the hidden port is a recent
issue.

I ran wireshark on this and it appears to create two ports for NFS. One
of them is canceled by the client (sends a FIN/ACK) and this port is
what lays around never to be used again, and uses the other port for
all connections after that.

When I unmount the NFS directory, the port is finally freed (but has no
socket attached to it). What is the purpose of keeping this port around?

I can reproduce this by having the client unmount and remount the
directory.

-- Steve