[Info-vax] TCP/IP v5.6-9ECO3 problem

[FrankS]

Follow up again.

I worked my way backwards through the ECOs with the following results:

v5.6-9 ECO 3  -- doesn't work
v5.6-9 ECO 2  -- doesn't work
v5.6-9 ECO 1 -- doesn't work
v5.6-9 -- doesn't work
v5.5-11 ECO 3 -- worked!

I have no idea why none of the v5.6 variants would fail, but that is
what happens.  As soon as the connection is attempted the FTP server
entered a CPU loop and just sits there spinning.

There must be something about the packets being sent that causes the
problem.  This particular site has a bunch of firewall, VPN, and VLAN
routers between the PC world and the OpenVMS world so perhaps
somewhere along the line the packets are getting munged in a way that
is not evident on a directly connected network.

I compared the TCPtrace output from the failed sessions with the
working sessions and don't see anything obviously different in the
content.  I'll have to check my home network (no firewalls, VPNs, or
VLANs involved) to see if the trace results show any variations.