I was scrutinizing how NSM work with NFS3. I had two machines: A was running FreeBSD7.1 and B was running Solaris10.
Here is my steps:
1. Lock a file in the NFS mounted FS from the client. I can see the NLM traffic in tcpdump. I'm pretty sure the lock indeed worked, because I verified it by locking the file again and failed on the twice lock.
2. Kill all the NFS related processes on the server. I verified this by their absence in ps and rpcinfo
3. Start all the NFS related processes on the server.
On the 3rd step I did not see any NSM traffic in tcpdump. I have tried this bidirectionally, i.e. FreeBSD as server with Solaris as client and FreeBSD as client with Solaris as server
I have two guesses:
1. My experiment was wrong, NSM is not designed to send SM_NOTIFY in the condition I fabricated.
2. NSM is disabled by default and needs to be enabled explicitly which I didn't do.
Of course there can be many other possibilities.
Here is my steps:
1. Lock a file in the NFS mounted FS from the client. I can see the NLM traffic in tcpdump. I'm pretty sure the lock indeed worked, because I verified it by locking the file again and failed on the twice lock.
2. Kill all the NFS related processes on the server. I verified this by their absence in ps and rpcinfo
3. Start all the NFS related processes on the server.
On the 3rd step I did not see any NSM traffic in tcpdump. I have tried this bidirectionally, i.e. FreeBSD as server with Solaris as client and FreeBSD as client with Solaris as server
I have two guesses:
1. My experiment was wrong, NSM is not designed to send SM_NOTIFY in the condition I fabricated.
2. NSM is disabled by default and needs to be enabled explicitly which I didn't do.
Of course there can be many other possibilities.