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Article #3599Re: "startup" of smtp connection timeout
From: Neil W Rickert
Date: Thu, 13 Feb 2003 00:01
Date: Thu, 13 Feb 2003 00:01
26 lines
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1947 bytes
"Jeremy Fitz" <jeremyfitz@hotmail.com> writes:
>Is the gethostbyaddr executed via a reverse DNS lookup?
Yes.
>- what is done with the result?
It is used to set ${client_name}
>- what happens if the reverse lookup doesn't return anything (isn't
>populated for my host), or returns the incorrect result?
The failure is indicated in ${client_resolve}, and ${client_name} is
set to [ip-address]
>- could this account for delayed or non-successful "startup"?
The time taken for the lookup is the problem. Failed lookups often
take longer than successful lookups (retries at several
nameservers).
>How is a "forged" address detected via the gethostbyname() call?
The ip addresses from gethostbyname should include the original ip
address. Otherwise DNS spoofing might be in use.
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X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103334,f0a437c1cf624342 X-Google-Attributes: gid103334,public X-Google-Thread: 115632,f0a437c1cf624342 X-Google-Attributes: gid115632,public X-Google-Thread: 10de99,f0a437c1cf624342 X-Google-Attributes: gid10de99,public X-Google-Thread: 109af8,f0a437c1cf624342 X-Google-Attributes: gid109af8,public X-Google-ArrivalTime: 2003-02-12 16:10:19 PST Path: arc1-ca.pugleaf.net!archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news.uchicago.edu!vixen.cso.uiuc.edu!husk.cso.niu.edu!not-for-mail From: Neil W Rickert <rickert+nn@cs.niu.edu> Newsgroups: comp.mail.sendmail,cz.comp.mail.sendmail,microsoft.public.exchange.connectivity,microsoft.public.isa.configuration Subject: Re: "startup" of smtp connection timeout Date: 13 Feb 2003 00:01:50 GMT Organization: Northern Illinois University Lines: 27 Message-ID: <b2en9e$4mo$1@husk.cso.niu.edu> References: <Noj2a.330858$pDv.239830@news04.bloor.is.net.cable.rogers.com> <b2cj6d$n2c$1@husk.cso.niu.edu> <Afx2a.657729$F2h1.167789@news01.bloor.is.net.cable.rogers.com> NNTP-Posting-Host: euclid.cs.niu.edu User-Agent: nn/6.6.5