Re: got TCP reply: Z

Justin Dolske (
Fri, 23 May 1997 17:11:55 -0400 (EDT)

On Fri, 23 May 1997, Seth D. Schoen wrote:

> Two questions of interpreting logs from u2t:
> Empty TCP reply.
> got TCP reply: Z
> Both of these have showed up in our u2t log at various times. What do they
> indicate and where does that suggest the problem, if any, lies?

Empty TCP reply means that the connection between the gateways was closed
before a reply from the keyserver was received. This is most commonly due
to a UDP message being lost somewhere, and really isn't a big deal. The
client will also time out, and will resend the message.

I'm not sure why you're getting a plain "Z" -- maybe Rocke's server is
sending it for some reason?

The gateways will only kill a client (Z) in two cases:

* The U2T gateway receives an empty UDP message from a client
* The T2U gateway receives an empty request from the U2T gateway.

Both should never (or rarely) happen, and both give more descriptive "Z"

Justin Dolske <URL:>
Graduate Fellow / Research Associate at The Ohio State University, CIS Dept.
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