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Topic review

martin

Re: Server unexpectedly closed network connection

As both sides consider this an unexpected connection loss, possibly something it interrupting your connection.
MagnusH

Server unexpectedly closed network connection

Hey,

I'm having some problems and I cannot seem to work out the problem. I've looked through FAQ:s and Guides but I'm now getting any wiser.

We're using WinSCP to log on to a SFTP-server using private keys in Pageant. With both the exe and the com we always get the error "Server unexpectedly closed network connection" the first time we log on. In the exe I can click "Reconnect" and it works and in the com I can just run the open command once again and it works.

I've checked with the SFTP-admins and they have no records in the FTP-log of our logon attempt but they do get this in there Key exchange log:

[2009-07-16 10:52:06.639] ERROR [TransportProtocol] Connection Error

java.io.IOException: Client did not send complete packet in key exchange! Possible DoS attack


Our WinSCP log:

--------------------------------------------------------------------------

WinSCP Version 4.1.9 (Build 416) (OS 5.1.2600 Service Pack 2)
Login time: Tuesday, July 14, 2009 11:15:41 AM
--------------------------------------------------------------------------
Session name: swedbank
Host name: XXX.XX.XX.XX (Port: 10022)
User name: username (Password: No, Key file: No)
Tunnel: No
Transfer Protocol: SFTP (SCP)
Ping type: -, Ping interval: 30 sec; Timeout: 15 sec
Proxy: none
SSH protocol version: 2; Compression: No
Bypass authentication: No
Try agent: Yes; Agent forwarding: No; TIS/CryptoCard: No; KI: No; GSSAPI: No
Ciphers: aes,blowfish,3des,WARN,arcfour,des; Ssh2DES: No
SSH Bugs: -,-,-,-,-,-,-,-
SFTP Bugs: -,-
Return code variable: Autodetect; Lookup user groups: Yes
Shell: default, EOL: 0
Clear aliases: Yes, Unset nat.vars: Yes, Resolve symlinks: Yes
LS: ls -la, Ign LS warn: Yes, Scp1 Comp: No
Local directory: default, Remote directory: home, Update: No, Cache: Yes
Cache directory changes: Yes, Permanent: Yes
DST mode: 1
--------------------------------------------------------------------------
Looking up host "XXX.XX.XX.XX"
Connecting to XXX.XX.XX.XX port 10022
Selecting events 63 for socket 480
Waiting for the server to continue with the initialisation
Looking for incoming data
Looking for network events
Detected network event
Enumerating network events for socket 480
Enumerated 18 network events making 18 cumulative events for socket 480
Handling network write event on socket 480 with error 0
Handling network connect event on socket 480 with error 0
Looking for network events
Detected network event
Enumerating network events for socket 480
Enumerated 1 network events making 1 cumulative events for socket 480
Handling network read event on socket 480 with error 0
Server version: SSH-2.0-http://3sp.com_Maverick_SSHD
We claim version: SSH-2.0-WinSCP_release_4.1.9
SSPI: acquired credentials for: username@user.LOCAL
Cannot convert IP address to SPN: DNS is not trusted
GSSKEX disabled: Incorrect function.

Using SSH protocol version 2
Waiting for the server to continue with the initialisation
Looking for incoming data
Looking for network events
Detected network event
Enumerating network events for socket 480
Enumerated 1 network events making 1 cumulative events for socket 480
Handling network read event on socket 480 with error 0
Using Diffie-Hellman with standard group "group14"
Doing Diffie-Hellman key exchange with hash SHA-1
Waiting for the server to continue with the initialisation
Looking for incoming data
Looking for network events
Detected network event
Enumerating network events for socket 480
Enumerated 32 network events making 32 cumulative events for socket 480
Handling network close event on socket 480 with error 0
Selecting events 0 for socket 480
Server unexpectedly closed network connection
(ESshFatal) Server unexpectedly closed network connection.


Any ideas?