On 2007-05-31 at 08:49 +0100, Alun wrote:
> On 22nd May we upgraded our mail servers to exim 4.67. Since then we've
> been having problems with mail from wales.ac.uk. Mail from them
> originates from 194.80.131.5 which has multiple reverse DNS records.
> Obviously I can whitelist the specific IP (and others, as they come
> along), but I thought I'd just raise this here - I can't see anything
> in the ChangeLog that specifically mentions the change. Was this
> intentional or a bug?
I can see one which might be relevant. Exim 4.64:
PH/48 When a host name was looked up from an IP address, and the subsequent
forward lookup of the name timed out, the host name was left in
$sender_host_name, contrary to the specification.
So now, the forward DNS resolution has to work correctly, always.
You can debug with: exim -d+acl -bh 194.80.131.5
Which for me yields the below, during setup. Given that this is Exim
complaining about no IP found, I suspect that the DNS changed around
this time too and it's not really related to the Exim change.
Unfortunately the administrators of 131.80.194.in-addr.arpa. are not
using date-encoding for the SOA serial number, so I can't confirm this.
----------------------------8< cut here >8------------------------------
LOG: smtp_connection MAIN
SMTP connection from [194.80.131.5]
host in host_lookup? yes (matched "*")
looking up host name for 194.80.131.5
DNS lookup of 5.131.80.194.in-addr.arpa (PTR) succeeded
IP address lookup yielded *.ezproxy.library.wales.ac.uk
alias mail.cymru.ac.uk
alias mail.wales.ac.uk
alias uwrz05.wales.ac.uk
alias uwrz46.cymru.ac.uk
alias uwrz46.wales.ac.uk
alias ezproxy.library.wales.ac.uk
gethostbyname2(af=inet6) returned 4 (NO_DATA)
gethostbyname2(af=inet) returned 3 (NO_RECOVERY)
no IP address found for host *.ezproxy.library.wales.ac.uk (during SMTP connection from [194.80.131.5])
*.ezproxy.library.wales.ac.uk in dns_again_means_nonexist? no (option unset)
temporary error for host name lookup
sender_fullhost = [194.80.131.5]
sender_rcvhost = [194.80.131.5]
set_process_info: 13298 handling incoming connection from [194.80.131.5]
----------------------------8< cut here >8------------------------------
