On Tuesday, July 17, 2012 02:21:43, Muhammad Irfan wrote:
> I normally sends mass no. of emails via script twice per day (around 40000
> emails) each email contains one recipient.
> And my script will sleep for 5 seconds after every 1000 emails. I noticed
> many exim processes running when script exeuctes
> and around 20-30% emails stucks in queue and server load is quite high
> during mass mailing.
> What are the specific parameters to optimize outgoing mass emails ? Is
> there any way to throttle outgoing emails ?
>
> Furhter, i noticed stuck(queued) emails logs describes.
>
> * Recipient address rejected: Greylisted for 2 minutes
> * 451 Temporary local problem - please try later
> * R=dkim_lookuphost defer (-1): host lookup did not complete
>
> To me it's look likes recipient addresses are not accepting my emails.
Sort of, and not exactly.
> Probably DNS, RDNS or SPF issue. right or wrong ?
I don't think this is RDNS or SPF is related.
* Greylisting:
https://en.wikipedia.org/wiki/Greylisting
* "451 Temporary local problem - please try later" is usually the response
when a local configuration error has been reached. So for instance if you
have written an ACL rule that has an error in it and an incoming SMTP
connection reaches it, a "Temporary local problem" will result.
* With DKIM the verifier uses DNS to retrieve the signer's public key to
verify the signed mail.
DKIM:
https://en.wikipedia.org/wiki/DomainKeys_Identified_Mail
The lookup failing likely means the DNS lookup timed out. DNS [normally] uses
UDP which means the packets are not guaranteed to arrive, so these can get
lost if (for instance) the packet queue on the router or switch is full such
that some incoming packets have to be dropped.
> and for successfull outgoing emails normally log describes
> * SMTP Outbound Connection ..
> what does that means ?
Without context it's hard to know, but it sounds like what it says -- that an
outbound SMTP connection is/was made.
-- Chris
--
Chris Knadle
Chris.Knadle@???
