Author: Odhiambo Washington Date: To: Exim Users Subject: Re: [Exim] Very Slow response: exim -bt
* Philip Hazel <ph10@???> [20010809 17:40]: writing on the subject 'Re: [Exim] Very Slow response: exim -bt' > On Thu, 9 Aug 2001, Odhiambo Washington wrote:
>
> > Here now comes a better output:
>
> For those who may not understand why the first -d9 run was very sparse:
> in modern versions of Exim, you have to be an admin user to set any
> debug level > 1.
While this is true, I also did a test run with -d 5 while logged in as
root but the output was still that minimal until I installed db-3.2.9
and I was wondering if this is necessary for Exim to run. Excuse my dumb
approach. I almost wondered if db-3 or whatever version is a runtime
dependancy, but it isn't, from the results below
longonot# cd /usr/ports
longonot# make search key=exim
Port: exim-3.32
Path: /usr/ports/mail/exim
Info: High performance MTA for Unix systems on the Internet
Maint: sheldonh@???
Index: mail
B-deps: XFree86-3.3.6_9
R-deps: XFree86-3.3.6_9
Port: exim-ldap-3.32
Path: /usr/ports/mail/exim-ldap
Info: High performance MTA for Unix systems on the Internet
Maint: sheldonh@???
Index: mail
B-deps: XFree86-3.3.6_9 openldap-1.2.11_2
R-deps: XFree86-3.3.6_9 openldap-1.2.11_2
Port: exim-ldap2-3.32
Path: /usr/ports/mail/exim-ldap2
Info: High performance MTA for Unix systems on the Internet
Maint: sheldonh@???
Index: mail
B-deps: XFree86-3.3.6_9 db3-3.2.9_2 openldap-2.0.11_4
R-deps: XFree86-3.3.6_9 db3-3.2.9_2 openldap-2.0.11_4
[snip]
#####
> > DNS lookup of mail.wananchi.com (A6) gave TRY_AGAIN
> > mail.wananchi.com in dns_again_means_nonexist? no (end of list)
> > returning DNS_AGAIN
> > DNS lookup of mail.wananchi.com (AAAA) gave TRY_AGAIN
> > mail.wananchi.com in dns_again_means_nonexist? no (end of list)
> > returning DNS_AGAIN
> > DNS lookup of mail.wananchi.com (A) succeeded
>
> Presumably the delay was in those two lookups for IPv6 DNS records (A6
> and AAAA). The DNS server, instead of saying "no such record" instantly,
> gave a timeout. That means there is a problem with the DNS server.
I will re-bond with the BIND thing again. Thanks for pointing out the
issue.
>
> Solution: recompile Exim without IPv6 support, unless you are
> particularly interested in running IPv6.
Makes me start asking for pointers to the FAQ that dwells on running exim
with IPv6 although in most parts of Africa we're yet to start playing with
it in production environments ;-)
I'm not saying that I did even have a flicker of doubt on the solution
proposed by Mr. Hazel but just for the record (for the benefit of other
FreeBSD users who aren't running IPv6 as yet and who might be tempted to
build Exim from the ports without disabling the protocol in the
Makefile) I wish to state that after the advise, it now behaves as I
would have expected.
> [Aside: at the IETF meeting that I'm currently attending, the consensus
> at a discussion of AAAA vs A6 records was to use only AAAA records, and
> not to proceed with A6. So the next release of Exim will have A6 support
> removed.]
Aaah, no need for my advise then, it wouldn't be there.
