I suppose I should pose the question to folks that use NFS, do you use TCP or UDP for your NFS stack?
On Mon, Mar 21, 2016 at 3:29 PM James A. Robinson <jim.robin...@gmail.com> wrote: > Running a packet trace while the problem was occurring let me see that the > problem is that the NFS layer isn't even being involved for 3 minutes due > to the TCP layer retrying for 3 minute before notifying the caller of the > error. > > The client sends SYN packets, doesn't get an ACK, and finally times out > after 3 minutes. The documentation for Linux (the client in this case) > indicates the following default: > > tcp_syn_retries (integer; default: 5; since Linux 2.2) > The maximum number of times initial SYNs for an active TCP > connection attempt will be retransmitted. This value should > not be higher than 255. The default value is 5, which > corresponds to approximately 180 seconds. > > I think this means that it's not possible to get faster failover w/o > modifying the default values for the TCP layer. This particular error is > always going to take at least 3 minutes to surface. > > Jim > >
