[CentOS] system smtp server question

mouss mouss at netoyen.net
Thu Feb 7 12:22:42 UTC 2008


Luke Dudney wrote:
> There are lightweight SMTP clients that can be used as drop-in 
> sendmail(1) replacements by speaking directly to a remote SMTP server 
> instead of dropping the message in the local queue directory. One that 
> I've used is mini_sendmail 
> (http://www.acme.com/software/mini_sendmail/), though this was a while 
> ago but I seem to recall having some success with it.
>
> Others have mentioned the trade-off between the additional complexity 
> of maintaining an MTA on each system and the fault-tolerance such a 
> setup provides, however, you can achieve similar levels of fault 
> tolerance by implementing redundancy on your relay server system(s). I 
> guess it's up to you to figure out what's appropriate to your 
> environment.

it's not a redundancy issue. it's a queue issue. when cron sends mail 
and if the sendmail command fails, cron can't do anything (it won't 
queue mail and retry later).

That said, one can write a script (perl comes to mind) or program that:
- replaces sendmail
- tries to send, and if it fails saves the message in a queue
- runs periodically (from cron for example) to check the queue

but I am not convinced that setting this up on every machine would be 
easier than configuring postfix or sendmail as a "null client".



More information about the CentOS mailing list