FTP Slow From Alpha to External Sites

[Robert Atkinson]

OK, stats from TCP/IP client are :-

TCP Source Port = 60990, TCP Destination Port = 20
TCP Sequence Number = 1774038205 = ^x69BDACBD
TCP Acknowledge Number = 551081025 = ^x20D8D441
Flags (URG=0,ACK=1,PSH=0,RST=0,SYN=0,FIN=0),
Window = 61440 = ^xF000
TCP Checksum = ^x931D, Urgent Pointer = 0 = ^x0000

Averages a window size of around 60,000.

ALPHA::RAA_RobertAtki0 09:58:13 TCPIP$FTP CPU=00:00:29.94 PF=60524 IO=174504 MEM=384
PUT (IMAGE) 860160 bytes 00:00:35.88 elapsed (23.41 KB/S)
Local: SYS$SYSROOT:[SYSEXE]SYSDUMP.DMP;3
Remote: test_tbs_sysdump3.dmp

Averages around 25KB/s


I also tried the Madgoat client, and results are similar.

Rob.

[Wim Van den Wyngaert]

You are doing a put, so the window size of the external node is the one that is important (you read and send, the external node receives in window size buffers and writes these to disk). NAs long as there is a lot of space in the window, the sender is not waiting for an ack.

Did you also check tracerout to see if the same rout is followed ?

A snapshot of the tcptrace could also be useful.

Wim

[Robert Atkinson]

Full trace attached

[Wim Van den Wyngaert]

Rob,

Could you post it as .txt ? Bank security ...

Wim

[Petr Spisek]

Rob, did you try traceroute from both comps to your external server? Did you compare number of hops and latency? When you checked routes.

I'm back with route config :-)

Petr

[Robert Atkinson]

8MB text file breaks ITRC 1MB limits!

[Robert Atkinson]

U:\>tracert dropbox-mun.emea.compaq.com

Tracing route to dropbox-mun.emea.compaq.com [161.114.112.193]
over a maximum of 30 hops:

1 <10 ms <10 ms <10 ms 10.110.16.1
2 <10 ms <10 ms <10 ms 10.110.16.255
3 1 ms 1 ms 1 ms randhous02-gw-lan.pipex.net [62.190.210.62]
4 * * * Request timed out.
5 * * * Request timed out.
6 * * * Request timed out.
7 * * * Request timed out.
8 * * * Request timed out.
9 * * * Request timed out.


ALPHA_ROB$$$ tracerou dropbox-mun.emea.compaq.com
traceroute to dropbox-mun.emea.compaq.com (161.114.112.193): 1-30 hops, 38 byte packets
1 10.110.16.1 (10.110.16.1) 0.977 ms 0.976 ms 0.0 ms
2 * * *
3 * * *
4 * * *
5 * * *


Our firewall doesn't allow our Alpha to TRACEROUTE past it, but I'll see if I can alter this.

Not sure why I'm getting time-outs after the 3rd hop from the PC?

Rob.

[Wim Van den Wyngaert]

I guess that the nodes don't react on your requests or may be the firewall is blocking them. Did you notice the difference in timing to reach the first node ?

Could you post the first MB of the trace ?

Wim

[Robert Atkinson]

Full Alpha traceroute :-

ALPHA_ROB$$$ tracerou dropbox-mun.emea.compaq.com
traceroute to dropbox-mun.emea.compaq.com (161.114.112.193): 1-30 hops, 38 byte packets
1 10.110.16.1 (10.110.16.1) 0.0 ms 0.976 ms 0.977 ms
2 10.110.16.255 (10.110.16.255) 0.976 ms (ttl=128!) 0.977 ms (ttl=128!) 0.976 ms (ttl=128!)
3 randhous02-gw-lan.pipex.net (62.190.210.62) 0.977 ms (ttl=254!) 1.95 ms (ttl=254!) 0.976 ms (ttl=254!)
4 * * *

[Petr Spisek]

What does it mean the second hop? Is it a broadcast?
Petr