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Question:

I don't know why sftp connect failed

Jul 25 '14 at 10:40

please let me know reason

=============================================================================

2014.07.24 14:32:48 FTP Connection Error.

Server Name : 10.179.113.161, Port# : 22.

ChilkatLog:

Connect_SFtp:

DllDate: Jun 10 2014

ChilkatVersion: 9.5.0.40

UnlockPrefix:

Username:

Architecture: Little Endian; 32-bit

Language: Visual C++ 10.0 (32-bit)

VerboseLogging: 0

SftpVersion: 0

hostname: 10.179.113.161

port: 22

Established TCP/IP connection with SSH server

clientIdentifier: SSH-2.0-PuTTY_Local:_May_11_2009_17:22:38

Sending client identifier...

Done sending client identifier.

Reading server version...

initialDataFromSshServer: SSH-2.0-OpenSSH_4.3

serverVersion: SSH-2.0-OpenSSH_4.3

KeyExchangeAlgs:

  algorithm: diffie-hellman-group-exchange-sha1

  algorithm: diffie-hellman-group14-sha1

  algorithm: diffie-hellman-group1-sha1

--KeyExchangeAlgs

HostKeyAlgs:

  algorithm: ssh-rsa

  algorithm: ssh-dss

--HostKeyAlgs

EncCS:

  algorithm: arcfour

  algorithm: aes128-ctr

  algorithm: aes192-ctr

  algorithm: aes256-ctr

--EncCS

EncSC:

  algorithm: arcfour

  algorithm: aes128-ctr

  algorithm: aes192-ctr

  algorithm: aes256-ctr

--EncSC

MacCS:

  algorithm: hmac-sha1

--MacCS

MacSC:

  algorithm: hmac-sha1

--MacSC

CompCS:

  algorithm: none

  algorithm: zlib@openssh.com

--CompCS

CompSC:

  algorithm: none

  algorithm: zlib@openssh.com

--CompSC

Unable to agree upon server-to-client encryption algorithm.

Unable to agree upon client-to-server encryption algorithm.

MAC: HMAC-SHA1

MAC: HMAC-SHA1

Compression: zlib@openssh.com

Compression: zlib@openssh.com

Key Exchange: DH Group Exchange SHA1

Host Key Algorithm: DSS

numBits: 128

pbits: 1024

Using GEX Group.

Sending KEX_DH_GEX_REQUEST...

pbits: 1024

sshRawPacket: Socket connection closed.

sshDhGex: Socket connection closed.

Failed to read KEX_DH_GEX_REQUEST response

Failed.

--Connect_SFtp

--ChilkatLog


Answer

I was not able to connect to that server. However, I see the following in the LastErrorText:

Unable to agree upon server-to-client encryption algorithm.

Unable to agree upon client-to-server encryption algorithm.

But this make no sense because Chilkat supports the encryption algorithms listed by the server. I'd need to establish a connection to that server for testing..


Answer

Apparently your server is OpenSSH 4.3 (which is somewhat old) and my information indicates that OpenSSH (at that time) did not correctly implement the AES CTR mode algorithms. Chilkat does not indicate support for the AES CTR algorithms when the SSH server is OpenSSH 3. or 4.. These versions of OpenSSH are circa 2006. The latest release is OpenSSH 6.6: March 16, 2014


Answer

I get the same issue from time to time, so on 1st failure I send the file to a retry server, and it continues to fail over and over.

If I initiate the transaction as new it works. The destination server does have a problem and they do some sort of reset.

You said 6.6 what is this 7.5??

initialDataFromSshServer=SSH-2.0-WS_FTP-SSH_7.5