Win7 workstation -> LAN -> ASA -> Cisco ASR -> DMVPN -> ASR -> Palo Alto -> Nexus -> NetApp
We are experiencing the symptoms described in the title. This is not new, it predates me, and it happens at multiple spoke sites in our DMVPN. Each vendor just seems to point the finger at the other with no real data reinforcing their point. Cisco has cleared any real issues at the hardware level.
asked 28 Sep '16, 11:57
At the end of my talk about SMB2 during Sharkfest Europe I have invited the attendees to look at this post to get a feeling for the protocol. I guess, people are interested in SMB2 since the view counters went up over the last week.
My analysis can be found on Jasper's blog as it became too big for this website.
Any comments, add-ons etc are very welcome.
answered 28 Oct '16, 12:33
My 2 cents:
C_to_H_200MB: Trace taken on the sender side. Throughput is linearly increasing till 240Mbit/s at the end, like the receiver window size, growing all along. Windows size is not filled from sender point of view.
H_to_C_200MB: Trace taken on the receiver side. Throughput grows linearly (max of 180Mb/s), but is stopped each time there's a retransmission, sender seems to be very sensitive to that.
I'd make the test with a Linux & macOS client.
If changes, I'd check and disable some "Slow start" / Heuristic features of Windows:
http://betanews.com/2011/01/20/use-hidden-windows-tweaks-to-speed-up-your-internet-and-network-connections/ https://www.duckware.com/blog/how-windows-is-killing-internet-download-speeds/index.html http://www.speedguide.net/faq/windows-scaling-heuristics-changes-my-tcp-autotuning-339
Else, throughput is high, and RTT of 30ms, I'd try to open more both RX windows size and TX buffer at the beginning of the TCP connection to see if transfer throughput is no longer linearly growing.
answered 27 Oct '16, 04:58