edouard.boucher@??? wrote:
> hi,
>
>
>>>I am trying to set up a router which act like dnslookup,
>>>but discard all the MX record that are not primary, and fail if no MX record.
>>>is the easiest way to set this a hack in src/routers/dnslookup.c ?
>>
>
>>I hope you don't want to apply this rule to all outgoing mail. Some
>>people use to have reasons for having multiple (e.g. IPv6 only primary
>>MX) or no (reduce number of DNS RRs in conformance with RFC821) MX.
>
>
> I want to use this kind of routing only for a very specific case.
> it is not my default router !
>>Otherwise have a look at dnsdb lookups and the manualroute router.
> i tryed but a dnsdb gives a list of all the mx,
> and i have no idea of how to extract only the lowest.
run the result through an external command, or use some fancy recursive
calling of the router and a tricky usage of address_data
I don't know if this set of routers will work, i just wrote them down,
without testing, whatever, but maybe you can see what i want to do, and
how it could be done.
# First lookup the MX records and save it in address_data
lookup_mx:
driver = redirect
domains = +backup_domains
address_data = ${lookup dnsdb {MX=$domain}}
data = $local_part@$domain
redirect_router = loop_mx
# Loop until we have NO newline left in our address_data
# in every loop we compare the first two MX values to each
# other, and strip the one with the bigger value
loop_mx:
driver = redirect
domains = +backup_domains
condition = ${if match {$address_data}{\\n}{1}}
address_data = ${if match {$address_data} \
{\N(\d+)\s+([^\n]+)\n(\d+)\s+([^\n]+)(.*)\N} \
{${if < {$1}{$3} {$1 $2$5}\
{$3 $4$5}}}\
}
data = $local_part@$domain
redirect_router = loop_mx
# this finaly routes the domain, with the host in $address_data
route_domain:
driver = manualroute
domains = +backup_domains
condition = ${if eq {}{$address_data}{1}{0}}
route_data = ${extract {2}{ }{$address_data}}
Any comments?
ciao
