Hi,
I have been running a simple test using two clients (one FreeBSD
and the other Linux, Ferdora Core30, 5.2 kernel) with delegations
enabled in the server.
The test consists of running the connectathon general tests
alternately om each client, using the same directory on the
server.
--> As such, each one results in CB_RECALLs of delegations
from the other client.
Everything seems fine until the server does multiple concurrent
CB_RECALLs for different files/delegations using different
callback session slots.
--> Then the Linux client decides it must create a new connection,
which breaks the back channel.
After 0.1sec, the FreeBSD server notices the broken back
channel and starts setting SEQ4_STATUS_CB_PATH_DOWN.
--> 15sec after that, the Linux client does a BindConnectionToSession
and things start working again.
The mystery to me is why the client decides to create a new TCP
connection, forcing this 15sec hickup each time it happens?
If you are interested in looking at a packet capture. you can
% fetch https://people.freebsd.org/~rmacklem/twoclientdeleg.pcap
There are multiple examples in it. One is at:
packet# 3518, 3520, 3521 CB_RECALL requests for 3 different delegations
time 137.5
--> This is followed by a close and open of a new TCP connection...
packet# 3582 - first one with SEQ4_STATUS_CB_PATH_DOWN at
time 137.6
packet# 3604 - client does a bindconnectiontosession at
time 152.7
Then things start to happen again...
192.168.1.5 - FreeBSD server
192.168.1.6 - Linux client
192.168.1.13 - FreeBSD client
If this is a known issue that you think is fixed in a more recent
Linux kernel, then sorry about the noise.
rick
