I run linux/sendmail-8.13.8 at home to host my domain. Some domains will
not accept mail from me because my address is from a dynamic address pool
so I solved that problem by placing all of those domains in my mailertable
and now route those messages through my ISP. Recently I have noticed that
some of the mail is hanging for a while with 400 series messages saying
'Too many connections'. I check with RCN and after many wated hours on
hold I found out that I need to limit the maximum number of connections to
their SMTP server to 4. Four shall be the counting. Five is too many and
six is right out!

Can someone please tell me what the incantation is to limit the number of
simultaneous connections to a particular server?

TIA.

Steven W. Orr wrote:

> I run linux/sendmail-8.13.8 at home to host my domain. Some domains will
> not accept mail from me because my address is from a dynamic address pool
> so I solved that problem by placing all of those domains in my mailertable
> and now route those messages through my ISP. Recently I have noticed that
> some of the mail is hanging for a while with 400 series messages saying
> 'Too many connections'. I check with RCN and after many wated hours on
> hold I found out that I need to limit the maximum number of connections to
> their SMTP server to 4. Four shall be the counting. Five is too many and
> six is right out!
>
> Can someone please tell me what the incantation is to limit the number of
> simultaneous connections to a particular server?

Not the best solution but from the TWEAKING CONFIGURATION OPTIONS
section in SendmailConfigFiles (a.k.a. cf/README):

confSINGLE_THREAD_DELIVERY

If this option and the
HostStatusDirectory option are both
set, single thread deliveries to other
hosts. That is, don't allow any two
sendmails on this host to connect
simultaneously to any other single
host.

But something is strange in your system, sendmail usually sends all the
messages to one host over one connection... perhaps it is different if
you have a lot of messages (I don't think so but I'm not sure), you
could control that with the queue run time. My guess is that you
changed some of the default parameters and now they've come back and
bit you.
--
René Berber

On Sat, 09 Sep 2006 17:55:04 -0700, René Berber wrote:

>
> Steven W. Orr wrote:
>
>> I run linux/sendmail-8.13.8 at home to host my domain. Some domains will
>> not accept mail from me because my address is from a dynamic address pool
>> so I solved that problem by placing all of those domains in my mailertable
>> and now route those messages through my ISP. Recently I have noticed that
>> some of the mail is hanging for a while with 400 series messages saying
>> 'Too many connections'. I check with RCN and after many wated hours on
>> hold I found out that I need to limit the maximum number of connections to
>> their SMTP server to 4. Four shall be the counting. Five is too many and
>> six is right out!
>>
>> Can someone please tell me what the incantation is to limit the number of
>> simultaneous connections to a particular server?
>
> Not the best solution but from the TWEAKING CONFIGURATION OPTIONS
> section in SendmailConfigFiles (a.k.a. cf/README):
>
> confSINGLE_THREAD_DELIVERY
>
> If this option and the
> HostStatusDirectory option are both
> set, single thread deliveries to other
> hosts. That is, don't allow any two
> sendmails on this host to connect
> simultaneously to any other single
> host.
>
> But something is strange in your system, sendmail usually sends all the
> messages to one host over one connection... perhaps it is different if
> you have a lot of messages (I don't think so but I'm not sure), you
> could control that with the queue run time. My guess is that you
> changed some of the default parameters and now they've come back and
> bit you.

I see your point but I really don't think I've done anything weird. On the
off chance that I did something weird, I put my sendmail.mc and
mailertable at

http://steveo.syslang.net/sendmail.mc
http://steveo.syslang.net/mailertable

Does this ?

Steven W. Orr wrote:

[snip]
> I see your point but I really don't think I've done anything weird. On the
> off chance that I did something weird, I put my sendmail.mc and
> mailertable at
>
> http://steveo.syslang.net/sendmail.mc

Don't see any problem there (repeating features is an operator error
not a problem), what's your queue interval times?

> http://steveo.syslang.net/mailertable
>
> Does this ?

Not so far, what error messages do you see in sendmail's log before the
"too many connections" begin to appear?

Are you getting gray-listed by any chance?
--
René Berber

Steven W. Orr :

You seem to be using Majordomo, perhaps that is the cause of the
problem.

I don't know Majordomo but I've seen that it can use some
"enhancements" like bulk_mailer and TLB that will run multiple sendmail
queues.

So it probably wasn't sendmail by itself opening multiple connections,
which was the strange part, it could be either Majordomo itself running
sendmail several times or one of those add-ons. I don't know how to
correct that problem.
--
René Berber

On Sun, 10 Sep 2006 13:22:35 -0700, René Berber wrote:

>
> Steven W. Orr :
>
> You seem to be using Majordomo, perhaps that is the cause of the
> problem.
>
> I don't know Majordomo but I've seen that it can use some
> "enhancements" like bulk_mailer and TLB that will run multiple sendmail
> queues.
>
> So it probably wasn't sendmail by itself opening multiple connections,
> which was the strange part, it could be either Majordomo itself running
> sendmail several times or one of those add-ons. I don't know how to
> correct that problem.

I did some checking and I now have the following information. I am using
Majordomo2 (not to be confused with majordomo). MJ2 will VERP messages to
recipients who have a recent history of bounces. I was concerned that
that was a problem but I am convinced that it is not. Having said that, my
original question still stands.

I want to tell sendmail that it should not allow more than four
simultaneous connections to this one particular SMTP server.

Anyone?

Steven W. Orr wrote:

[snip]
> I did some checking and I now have the following information. I am using
> Majordomo2 (not to be confused with majordomo). MJ2 will VERP messages to
> recipients who have a recent history of bounces. I was concerned that
> that was a problem but I am convinced that it is not. Having said that, my
> original question still stands.
>
> I want to tell sendmail that it should not allow more than four
> simultaneous connections to this one particular SMTP server.
>
> Anyone?

In your MJ2 configuration, what do you have for numbatches?

The whole delivery_rules section can be the cause of running several
sendmail processes in parallel...
--
R.Berber

On Mon, 11 Sep 2006 14:07:40 -0700, René Berber wrote:

>
> Steven W. Orr wrote:
>
> [snip]
>> I did some checking and I now have the following information. I am using
>> Majordomo2 (not to be confused with majordomo). MJ2 will VERP messages to
>> recipients who have a recent history of bounces. I was concerned that
>> that was a problem but I am convinced that it is not. Having said that, my
>> original question still stands.
>>
>> I want to tell sendmail that it should not allow more than four
>> simultaneous connections to this one particular SMTP server.
>>
>> Anyone?
>
> In your MJ2 configuration, what do you have for numbatches?
>
> The whole delivery_rules section can be the cause of running several
> sendmail processes in parallel...

configset lname delivery_rules <<ENDAAT
ALL
hosts=(localhost=(port=24, timeout=600, esmtp, dsn))
ENDAAT

I don't mean to sound ungrateful, but I'm not going in the right direction
here. If there's an MJ2 problem then I'll be happy to deal with it myself
or on the mj2 list later. For now, can we please just ignore that fact
that I'm using mj2 and focus on the sendmail question at hand?

I have some number of messages to be delivered. Some of these messages
will be relayed through rcn. All I'm looking for is the configuration
option to specify to sendmail that when it sends mail out to rcn that the
number of connections to rcn be limited to a maximum of four. If sendmail
can't do that then that's fine too as long as I know.

Thanks.