4.1 no-pnfs mount option?
Subsystems (2)
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Hi,
Quoted 7 lines · ----- "Trond Myklebust
"Why would an administrator never want to do this?" is not a helpful question.
A more useful question is "what reason would you possibly have for overriding the server's request that you do pNFS when your client has pNFS support?" What makes pNFS so special that we must allow administrators to do this on a per-mount basis?
Well, I phrased my question the other way because I suspect such cases will be found, but I may not have found all of them.
Some thoughts on why I might wish to take a hand in the decision:
1. the client doing pnfs might behave badly due to a misconfiguration or outage, yet behave acceptably using ordinary nfsv4?
2. restricting the client to ordinary nfsv4 might be desirable for non-developer troubleshooting or other configuration work?
I apologize if neither is compelling.
Quoted 9 lines
Throwing more and more knobs into the kernel is easy. The difficult bit
is to figure out which are useful knobs, and that is why I want real use
cases...Trond
Matt
Signature · 11 lines
Matt Benjamin The Linux Box 206 South Fifth Ave. Suite 150 Ann Arbor, MI 48104 http://linuxbox.com tel. 734-761-4689 fax. 734-769-8938 cel. 734-216-5309
Quoted 12 lines · Matt W. Benjamin
Hi,
Quoted 7 lines · ----- "Trond Myklebust
"Why would an administrator never want to do this?" is not a helpful question.
A more useful question is "what reason would you possibly have for overriding the server's request that you do pNFS when your client has pNFS support?" What makes pNFS so special that we must allow administrators to do this on a per-mount basis?
Quoted 5 lines
Well, I phrased my question the other way because I suspect such cases will be found, but I may not have found all of them.
Some thoughts on why I might wish to take a hand in the decision:
1. the client doing pnfs might behave badly due to a misconfiguration or outage, yet behave acceptably using ordinary nfsv4?
The client should be automatically falling back to non-pNFS mode when this sort of thing happens (and, yes, we are already testing that kind of scenario).
In what cases do we expect the administrator to be able to detect that the client is misbehaving without the client itself being able to detect it and thus take action?
Quoted 1 line
2. restricting the client to ordinary nfsv4 might be desirable for non-developer troubleshooting or other configuration work?
That is the one-off testing case. You already have the option of removing and disabling the pNFS module to do your testing.
Quoted 14 lines
I apologize if neither is compelling.
Quoted 9 lines
Throwing more and more knobs into the kernel is easy. The difficult bit
is to figure out which are useful knobs, and that is why I want real use
cases...Trond
Matt
Signature · 6 lines
Trond Myklebust Linux NFS client maintainer NetApp [email protected] www.netapp.com