[lug] Re: ftp problem

Warren Sanders sanders at montanalinux.org
Tue Feb 12 15:05:32 MST 2002

Sean Reifschneider wrote:

>On Tue, Feb 12, 2002 at 01:06:06PM -0500, John Karns wrote:
>>This ftp server will require the ability to do a reverse-DNS lookup to see
>>where you are connecting from. If you get refused a connection because of
>>this then I cannot help you, the problem is at your end, contact your ISP.
>That may indeed be the case, and ideally you should have a reverse DNS
>entry for your machine (in particular, IRC servers tend to be pretty pissy
>if they can't do a reverse lookup).  However, I don't understand why somone
>would set up an FTP server to require this...  In fact, I don't really
>understand why *ANYONE* relies on reverse information.  Personally, I think
>the whole paranoid reverse/forward lookup like done with tcpwrappers is
>I can understand why you would do it if you rely on the reverse name for
>authentication, but I don't think that's a strong method of authentication
How does one remove this feature from ssh/http/ftp?  I just recently had 
this problem with my own server co-located.  I got with a new ISP and a 
static IP that was not reverseable and had lots of trouble connecting 
via all methods ssh/http/ftp to my RH6.2 and another RH7.2 server.  It 
took sometimes up to a full minute to get a login prompt.  Another 
instance, my uncle tried to ftp in using ws_ftp and kept timing out; his 
ISP just purchased a new address block and didn't get around to adding 
them to their hosts files.

After I added my IP to the hosts file on the two RH servers, all 
connections were instant.  After talking with my uncle's ISP, I got them 
to look into the same and it was soon fixed.  Anyway I did not 
intentionally set this feature up, so what can one do?

Warren Sanders

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