> -----Original Message----- > From: Chuck Lever [mailto:chuck.lever@xxxxxxxxxx] > Sent: Wednesday, September 21, 2011 4:06 PM > To: Jeff Layton > Cc: Myklebust, Trond; linux-nfs@xxxxxxxxxxxxxxx; skinsbursky@xxxxxxxxxxxxx > Subject: Re: [PATCH] nfs: set vs_hidden on nfs4_callback_version4 > > > On Sep 21, 2011, at 3:55 PM, Jeff Layton wrote: > > > This service should not be registered with or unregistered from rpcbind. > > I've been watching the larger conversation. One thing that registering does, > even if you don't want to advertise your service, is tell you if there is already > another service on that port. Do we want to worry about possible port > collisions for listeners like the callback service? We already have a module parameter for fixing the callback service so that we can avoid port collisions with known services. That said, normally we do not want to rely on the portmapper for detecting the existence of a service: that will in any case only detect RPC services and, as you point out below, is subject to stale entries. > Do we want to ensure that any other service on that port is unregistered? > We would already discover a listener on our port when trying to create the > socket, but an old registration may persist even after that old service has > gone away. If anyone tries to use the service which is advertised by the stale portmapper entry, then they will get a PROG_UNAVAIL error. Cheers Trond -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
