Re: FTP Connect - 30 secs delay -- MIDRANGE-L


Leif,

I think its safe to say that nobody knows what the problem is, all we can
do is _guess_.   As a computer person yourself, you must also realize that
hearing "I'm getting a 30 second delay" isn't enough information for
anyone to say to a certainty what the problem is.

So we're giving you suggestions that might help _you_ determine what the
problem is.

Here's what I'd do:

1) To see if the problem is on the AS/400, log onto the AS/400 and do
        a "FTP myaddress" on the AS/400 and see if you get the 30 sec
        delay.   If Patrick and Alexei are correct, the AS/400 is only
        looking up ITSELF and not your PC, so the DNS delay should be the
        same.

2) If you determine that there is no delay in Step 1, try a traceroute 
        (on Windows its "tracert") from the PC to the AS/400.  Look at 
        the system that works vs. the system that doesn't.  Are there
        packets being dropped?  Is the 30 second delay in one of the
        routers, etc?

3) At what point do you experience the delay?   On my AS/400, I get
        something like this:

        ftp as400 
        Connected to S10561BA.klements.com.
        -- There's often a delay here. --
        220-QTCP at AS400.KLEMENTS.COM.
        220 Connection will close if idle more than 5 minutes.
        Name (as400:klemscot): 

        The reason that I get this delay is because I'm using an old CISC
        system, and its very busy.  It takes the AS/400 a little while to
        create an FTP server job for me.  

        In your case the delay may at a different point.  Think to
        yourself "what is the system doing at this point that there might
        be a delay?"

4) If the delay is determined to be on the PC end, try uninstalling and
        reinstalling the network drivers.   I've had completely
        unexplainable problems get fixed on Windows by doing things like
        this.  Its one of the reasons I don't like to use Windows for
        anything.  (My desktop is running FreeBSD)

5) Make sure that in your network settings on the PC that DNS is disabled
        for EVERY TCP/IP -> ADAPTER BINDING.

If none of this helps, hire a network specialist to look at your
connection, there's only so much we can determine from the info you're
giving us.


On Thu, 4 Jan 2001, Leif Svalgaard wrote:

> I think, that FTP server code resolves it's own IP address via DNS, so even
> if you do not use DNS on a client, it is still being used on a server side.
> Alexei Pytel
> ----------
> You may not be doing a DNS lookup on your AS/400's IP address... but as
> soon as you connect the AS/400 is taking YOUR IP address and using DNS to
> find out the name of your client.
> Scott Klement
> ----------
> I actually asked IBM if the FTP was doing a lookup on the client IP address
> or name and the answer was a definitive "no". We had several customers
> experience this same problem. However, the FTP server does do a lookup on
> the AS/400 name.
> Patrick Townsend
> ---------
> The IBM AS/400 FTP server does a reverse lookup on its own domain name. If
> DNS is configured to be searched first it will take 30 seconds to fail over
> on the search and give you the user prompt
> Patrick Townsend
> ----------
> 
> I'm still confused.
> I have two PCs. They are both configured identically
> (disable DNS).
> 
> One can FTP to several AS/400s with no 30 sec delay.
> None of these AS/400 know anything about my PC.
> I'm connecting over the internet and my IP address
> changes every time.
> 
> The other is only connected (through a local 3COM router) 
> to one AS/400 and has the 30 sec delay.
> 
> Leif
> 

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