[Info-vax] Help to eliminate delay in establishing FTP connection (VMS V7.x on VAX with MultiNet V4.4)

[Tad Winters]

I'm hoping that you might give me some ideas to remediate this problem.

A long time customer, for whom I've done very little work for many
years, has been running with their solution for a very long time.
Within the last six weeks, they told me they were seeing delays in
connecting to the system with FTP.  He has been using PHP for many years
to upload some files to his VMS system to be processed by an
application.  He added some timing in the PHP calls and what it revealed
is a consistent 30 second delay from connecting until being logged in.
I confirmed this with Filezilla.

At first, I thought it must have something to do with DNS, as it
appeared the forwarders were all pointing to the internet, and I thought
it must be attempting to do some reverse lookup.
I made some changes, including defining a logical for MultiNet FTP to
have a fast timeout, and thought it would start working better.  Not so.

I modified a few FTP server setting, with the idea that the process may
be a little more snappy.  Logins from an interactive session to
localhost seem to occur with no delay, but from Filezilla, it's still 30
seconds of delay.

Thinking it might be part of the login stream, I copied the username to
a new account and modified that new account to have NLA0: for LGICMD.
It was late in the day, to I temporarily deassigned SYS$SYLOGIN, and
tried logging in again from Filezilla.  No change.

I ran MULTINET CHECK and it was generating errors.  I downloaded a new
named.cache file, corrected the file format and properly placed it.  I
also added the IP address from which I'm connecting and the IP address
of the default gateway to the hosts table, compiled and installed it,
and then restarted MultiNet.  After that, MULTINET CHECK reported no errors.

I used MULTINET SHOW /CONNECTIONS when I initiated my connection from
Filezilla, and repeated the command several times.  It was probably
about 20 seconds before the FTP connection showed up, but still a total
of 30 seconds before the client showed it was logged in.

The customer says he's not made any changes, including still using the
same version of PHP.  The VAX is virtualized with vtVAX on a physical
server running Windows Server, which the customer has said has had no
updates.  I don't know when he might have last changed the network
device, to which he indicates it is connected, but it wasn't recently.

It seems very strange that this started when "nothing" changed, and as I
said, my first thought was references to internet things, which can
change, might have caused such, but I feel like I've eliminated this.

What am I missing?

P.S. If DiBOL was available on the new VMS architecture, I'd love to
push for them to buy, but the Synergex product is far too expensive,
since they charge per seat for run time and the original DiBOL was a
free run time, only charging for the compiler.