Re: troubles with outgoing tcp/ip after sp1

cheers robert

this fixed my problems partially. indeed the max. MTU size my router(s) can
use is 1372. setting the MTU value for PPP and VPN cured the packetloss.

unfortunately, this didn't cure the ftp / mail / news upload problems:

[23:17:24] PORT 192,168,2,141,8,171
[23:17:24] 200 Port command successful.
[23:17:24] Opening data connection IP: 192.168.2.141 PORT: 2219.
[23:17:24] STOR id.jpg
[23:17:24] 150 Opening data connection for id.jpg.
[23:17:24] 2368 bytes sent successfully. (2.31 KB/s) (00:00:01).
[23:17:54] No response received from server. Timeout (30s).
[23:17:54] Connection closed.

while the ftp tool (here: smartftp, but same behaviour in comand line ftp)
thinks the 2368 bytes were sent successfully, the target server never got
any bits and bytes (id.jpg got size of 0 bytes on server). the 2368bytes
thus are put into the tcpip buffer where it *should* be sent by winsocks.
the application itself isn't even notified of any sending errors. only 30s
(after timeout waiting for server response) its socket is closed.

the interesting part: once the upload failed, a 2nd upload after the
connection timeout is most the time successfull. i got no clue, but i would
describe the problem as something like "delayed outbound socket creation"
:-)

this behaviour somewhat describe the same problems as discussed here:
http://www.microsoft.com/technet/community/newsgroups/dgbrowser/en-us/default.mspx?dg=microsoft.public.windowsupdate&tid=9b5c56c5-472e-4a60-a310-38ec9c9fca34&cat=en-us-technet-mgmt&lang=en&cr=US&sloc=en-us&m=1&p=1
unfortunately, KB893066 cannot be uninstalled in a slipstreamed w2k3 sp1...
and of course uninstalling an important hotfix is the least you want to do
anyway. but still better than not being able to use your windows
installation for your work...

- thomas


"Robert L [MS-MVP]" <noreply@xxxxxxxxxxx> wrote in message
news:ucL5bn6WFHA.1404@xxxxxxxxxxxxxxxxxxxxxxx
It could be the MTU issue. quoted from
http://www.howtonetworking.com/casestudy.htm
Case Study - VPN Connection issues after installed Windows server 2003 SP1
Situation: The client has been experiencing some VPN connection issues after
they installed Windows Server 2003 SP1. The main office has T1 line. The
branch office uses DSL line and some home users who are using DSL too. They
can establish the VPN, but they experience these issues:
The connection may drop in 2 or 3 minutes.
The VPN client may receive "The Network name is no longer available" message
when they transfer the data.
The RDC to TS may have black screen.
Resolution: Set my VPN client MTU to 1400.
To modify MTU, please refer to this page, How to change MTU settings for
PPP or VPN.
Related Topics
Connectivity issues after ms05-019 and 2003 sp1
Can't access some web sites
Black screen when RDP over VPN
Situation: The client has a site-to-site VPN setup with two Sonicwall
firewall. It works fine. He can ping anything on the remote sites and vice
versa.
Problem: When he tries to RDP to the server he gets the blank screen and the
banner at the top, but the log in window never appears and it eventually
times out and says broken network connection.
Troubleshooting: Since this is DSL line, we suspect this is MTU issue. So,
we use this commend "ping -l 1500 -f IP address" to test it. We receive
"Packet needs to be fragmented but DF set" and "Packets: Sent = 4, Received
= 0, Lost = 4 (100% loss)". That confirms that is MTU issues.

Resolution: Use the ping to test and lower MTU. Finally, We reduce MTU from
1500 to 1400 in the SonicWall. Then he can use RDC over VPN.
Related Topics
How to change MTU
Connectivity issues after ms05-019 and 2003 sp1
Troubleshooting terminal server issues
VPN drop connection
VPN slow issues

Don't send e-mail or reply to me except you need consulting services.
Posting on MS newsgroup will benefit all readers and you may get more help.

Bob Lin, MS-MVP, MCSE & CNE
How to Setup Windows, Network, Remote Access on
http://www.HowToNetworking.com
Networking, Internet, Routing, VPN Troubleshooting on
http://www.ChicagoTech.net
This posting is provided "AS IS" with no warranties.
"Thomas" <me@xxxxxxxxxxxxx> wrote in message
news:OuOZJo5WFHA.2692@xxxxxxxxxxxxxxxxxxxxxxx
after installation of w2k3 sp1 i have serious tcp problems.

the problems:
- 3-5% ping loss to *any* non-localhost-ip
- ftp uploads fail if file size is greater than 8kb ("unable to open data
connection" / "data connection timeout")
- outlook express fails to send out smtp mails ("unable to connect to
server")
- vpn connection breaks up every other minute

the setup:
- this is an out-of-the box configuration. the machine has 2 different
interfaces, both having these problems.
- windows firewall is disabled.
- tcp/ip filtering is disabled.
- windows 2000 on same machine works fine!

the workaround:
- packet loss: no clue so far
- sending out mails: when resetting the network interface (i.e.:
disabling/enabling the nic), operation works for a few minutes as it should.

it looks like some problems with the tcp-ip stack here. connecting to the
target socket works, but resulting in a timeout from time to time before any
data is sent.

any pointers how to further test and elaborate the problem is more than
welcome! i've spent hours trying and countless reinstals to solve this
problem without any luck.

would be sad to switch back to w2k ;-(

- thomas


.

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