Subject: inetd: ftp/tcp server failing (looping)

From: [email-masked] (Mike Erwin, System Administrator)
Date: Wed, 15 Mar 1995 13:38:17 -0600

Running 2.4(1).

Reported in /usr/adm/messages and to the console:

        inetd: ftp/tcp server failing (looping)

When trying to establish an ftp connection:

        ftp: connect: Connection refused

In restarting the machine, it see that after 30 or so people have logged
in, the server failing message comes up and the machine will no longer new
connections.

Has anyone seen this problem before?

-ME

|  "From the lightning in the sky, as it passed me flying by,
|   From the thunder and the storm, and the cloud that took the form,
|   (When the rest of heaven was blue), of a demon in my view."
| {10010 | 0111}  ˆ Veritas Aut Nihil! ˆ Heads- heads... heads?  heads!
|
|  Mike Erwin,       Development Engineer       Apple Computer, Inc.
|  [email-masked]  [email-masked]
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---

From: DaVe McComb <[email-masked]>
Date: Wed, 15 Mar 1995 15:18:02 -0500 (EST)

ME-
 
This problem is a result of running wuftpd from inetd.  inetd has a
feature in that if more than a specific number of connections   
are initiated in a certain amount of time, it thinks there's a problem and
proceeds to refuse ("loop") any additional connections for some amount of 
time before going back to it's normal state.  This is supposed to prevent
denial-of-service attacks such as someone flooding you with telnet
requests.

Supposedly there is a vendor supplied patch for this, but I have been
unable to find it for SunOS.  Let me know if you have any better luck.
 
-DaVe
 [email-masked]               Information Security/Goldman Sachs
 Voice : (212) 357-1939         85 Broad St. 125B/16, NY, NY 10004