Fwd: backing up to a Drobo CIFS VFS: Error -11 sending data on socket to server, Bufferbloat?

[Robert Kudyba]

> One thing you can do is to search for all those SMB requests where
> there is no response. Of course since there are packet drops you might
> find a few of those, but you can search for (!smb2.request_in) &&
> (smb2.flags.response == 0) and that will show you all the requests for
> which there is no response.

Sorry still getting used to WS but I couldn't find (!smb2.request_in)
== but  (smb2.flags.response == 0) was there. Am I supposed to run
tshark on the exported results?

> Another thing you can do is look for where the connection drops.
> Search on (tcp.flags.reset == 1) || (tcp.flags.fin == 1) select one,
> and then filter for all packets on the connection (tcp,port ==
> portnum) where portnum is not 445 so you get just one TCP connection
> and then you can look at what happened at the end of that tcp
> connection.
>
> This last approach might be the best if the problem is that the Linux
> CIFS module is forgetting to send data at some point and we are not
> looking for a Write request that the Drobo did not respond to.

How do I ' filter for all packets on the connection (tcp,port ==
portnum) where portnum is not 445'?

Using the 2 searches here I get these kind of logs:

140622  25.417347 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293608973 Win=26508 Len=0 TSval=632244604 TSecr=2339550377
140623  25.417645 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293611869 Win=26508 Len=0 TSval=632244604 TSecr=2339550377
140624  25.417912 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293614765 Win=26508 Len=0 TSval=632244604 TSecr=2339550378
140625  25.417925 fedora → drobo TCP 11650 [TCP segment of a reassembled PDU]
140626  25.417942 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293617661 Win=26508 Len=0 TSval=632244604 TSecr=2339550378
140627  25.418193 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293620557 Win=26508 Len=0 TSval=632244604 TSecr=2339550378
140628  25.418662 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293623453 Win=26508 Len=0 TSval=632244604 TSecr=2339550378
140629  25.418672 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293626349 Win=26508 Len=0 TSval=632244604 TSecr=2339550379
140630  25.419048 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293629245 Win=26508 Len=0 TSval=632244604 TSecr=2339550379
140631  25.419076 fedora → drobo TCP 14546 [TCP segment of a reassembled PDU]
140632  25.419328 drobo → fedora TCP 66 445 → 34050 [ACK] Seq=228277
Ack=293632141 Win=26508 Len=0 TSval=632244604 TSecr=2339550379