On Thu, 12 Jul 2001, Sheldon Hearn wrote:
> I have the following smtp_banner option in my main Exim configuration
> section for exim-3.31:
>
> smtp_banner = $primary_hostname ESMTP Exim \
> ${lookup{$sender_host_address} \
> lsearch* {/usr/local/etc/exim/bannerversion} \
> {${expand:$value}}}
>
> The bannerversion file contains this line:
>
> *: [Test release]\r\nYou probably shouldn't be using this service.
>
> If the bannerversion file is absent (perhaps in some small window period
> during an update operation), the lookup fails and all incoming SMTP
> connections receive a 421 error as documented.
1. If you put the new version in place using rename (i.e. use mv), there
won't be a window when it doesn't exist.
> So, is there a way to ensure that a non-existent file for an lsearch is
> treated as if the lookup failed (in this case, null expansion)?
2. Non-existence of a file that you ask Exim to search is treated as a
serious error, so it fails the entire expansion. This is usually the
best thing to do.
3. At present, the use of "fail" in the expansion of smtp_banner is not
treated specially. I suppose I could make it carry on and use the
default banner. However, that doesn't help, because non-existence does
not behave the way you want.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
