Hi Ewald,

Are you getting and actual socket connection to the AIX box that is getting 
reset?  In a packet trace you would see the SYN SYNACK ACK handshake to 
complete the socket connection.  If not, it sounds like a firewall issue.  Have 
there been any firewall changes that could block port 21 outbound from your 
side or inbound to the AIX box?  Inbound to the AIX box is unlikely since ping 
worked.

Port 21 is typically blocked by default and is a favorite of security people to 
disable.


Steve Bireley
Vice-President
Product Development
BlueZone Software
1-404-364-1731
www.bluezonesoftware.com
BlueZone Secure FTP is Free


-----Original Message-----
From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of 
Ewald Roller
Sent: Friday, October 19, 2007 9:22 AM
To: [email protected]
Subject: FTP timeout on open request

Hello all...

for about four weeks we have a strange FTP problem.
A Servicemachine working for months and gathering data
from a remote system suddenly makes problems.
The FTP open to the remote system always gets a timout:

ftp 128.1.2.120 ( timeout 450 trace
VM TCP/IP FTP Level 440
Translate Table: STANDARD
about to call BeginTcpIp
Connecting to 128.1.2.120, port 21
SysAct 0 21 -2147417480 CC -1
==> Active open to host 128.1.2.120 port 21 from host 0 port 65535
Foreign host did not respond within OPEN timeout
Unable to connect to 128.1.2.120
Foreign host did not respond within OPEN timeout
Command:
quit
SysHalt has been Called
Ready; T=0.01/0.02 14:08:40

Ping and traceroute are working well.

This is z/VM 4.4, the remote system is an AIX system.

A tcpdump analysis by a network guru shows
that the z/VM FTP is resetting the packets receiving
from the open request to AIX system. But in the
tcpdump-file we find no reason for this behavior.

Any ideas ?

Thanks

Ewald Roller
Rolf Benz AG & Co. KG

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