Since version 5.8.12 Fetchmail doesn't exit on a failure to DNS-resolve
a mail server name. This is good.
But there are still some remaining problems with DNS lookups:
1) Fetchmail tries to resolve host names, ever there is nothing to do
(especially with option "--version"). I don't think, that this is
useful.
$ fetchmail --version
This is fetchmail release 5.8.12+NTLM+SDPS+SSL+INET6+NLS
Linux chemnitz 2.4.6 #1 Sam Jul 7 12:37:55 CEST 2001 i586 unknown
fetchmail: couldn't find canonical DNS name of pop3.web.de
fetchmail: couldn't find canonical DNS name of pop.gmx.net
...
all mailserver name lookups failed, exiting
2) Fetchmail doesn't start as a daemon, if all host names can't be
resolved. As a result, some automatic start scripts don't work
if there are temporary DNS and/or Internet connection problems
or if the users want's to start Fetchmail at boot time, but want's
to establish the Internet connection manually.
$ fetchmail --daemon 60
fetchmail: couldn't find canonical DNS name of pop3.web.de
fetchmail: couldn't find canonical DNS name of pop.gmx.net
...
all mailserver name lookups failed, exiting
My suggestion is, that DNS lookups should occur directly before a
connection. Because of some high-loaded POP3 servers, which use
Round-Robbin-DNS, I think, DNS answers should not be cached by
Fetchmail. In daemon mode, Fetchmail shouldn't exit, even if there are
no servers, that could be resolved.
Björn
--
Björn Voigt <bjoern(_at_)cs(_dot_)tu-berlin(_dot_)de>
WWW: http://user.cs.tu-berlin.de/~bjoern/