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Sending email without running sendmail/postfix as a daemon

You can send email without running sendmail of postfix as daemon. You cannot receive email if you are running them as daemons (unless you use POP or some other similar protocols).

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Fedora Core

: Sendmail and the sm-client

I am getting the following error when restarting sendmail:

[root@dedicated /]# service sendmail restart
Shutting down sendmail: [FAILED]
Shutting down sm-client: [FAILED]
Starting sendmail: [ OK ]
Starting sm-client: sendmail: fatal: flush queue mode requires no recipient

Errors like this have been posted in other threads. But I have yet to see a solution addressing the issue with specifics...or perhaps I missed. I am certainly a beginner in the Linux world, so I may not have understood the solution if it was coded deeply in the replies.

If someone would please explain exactly how sm-client relates to sendmail. I am (reasonably) aware of sendmail and postfix on general terms and in the linux directories and MAN pages. I have been searching for the sm-client server/daemon in MAN pages and websites and have not been able to find anything on it at all, other than enclosed in similar error messages. Also, what are some commands to stop or restart the sm-client seperately. Is there a specific order that the servers should be restarted? Is there a reason that the sm-client typically fails? Does it matter for the sendmail server that sm-client failed to restart? I would assume this would be a definite "yes"...

I'm not even sure I understand the relation ship between postfix and sendmail, much less sendmail and the sm-client. Here is what I would guess ...and I am not going to be upset if I'm wrong:

- sm-client is a process that ??????

- sendmail is the process that transfers mail to/from given networks (MTA). Basically this is the delivery process. Given that sendmail stops and starts sm-client, the sm-client (which I assume is abbreviated for "sendmail-client") must act as a subprocess for sendmail. Perhaps packaging the messages from a MUA -- or sm-client might be "SquirrelMail" that we use as a web interface for mail (MUA).

- postfix is a process that controls the mail system (in this case sendmail). The sendmail would act as a subprocess for postfix. sm-client is, thus, also being used by postfix.

Am I even close on this?????? Please help me fill in some of the blanks.


Registered: May 2001

Posts: 14,460

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Since you and mention Postfix it could be a mixup between running the "real" Sendmail and Postfix. If your /var/log/maillog shows errors about Postfix then it could be a problem with linkage in /etc/alternatives (see "alternatives --display mta") where Postfix is wrongly started as a form of "sendmail daemon" but with Sendmail arguments. Relinking should fix that. Sm-client is Sendmail (see "pgrep -lf Queue.runner" and /usr/share/docs/sendmail*).


LQ Newbie

Registered: Nov 2006

Location: Brentwood, TN

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Thank you for the reply. I'll check into the /etc/alternatives. I wasn't sure anyone wanted to reply Perhaps a setting somewhere calls the "postfix flush" command with an additional argument...or maybe sm-client has a similar command used to flush the mail queue? The message on the sm-client does talk about an argument that isn't needed....? That may be enough to get the failures to stop.

However, running any of the three commands
service sendmail stop
service sendmail start
service sendmail restart

shows a pair (or two for restart) for each sendmail and sm_client. So they are each seperate services/daemons, or why would they be listed like that together? Is sm-client an older (or newer) version of sendmail??? They must be two different services...or two different copies?

Just checked and this is the contents of "/etc/alternatives":
[root@localhost root]# more /etc/alternatives

*** /etc/alternatives: directory ***

[root@localhost root]#

Contents of "/usr/share/docs/sendmail" (or lack of):
[root@localhost root]# more /usr/share/docs/sendmail
/usr/share/docs/sendmail: No such file or directory
[root@localhost root]#

Running the command "pgrep -lf Queue.runner":
[root@localhost root]# pgrep -lf Queue.runner
[root@localhost root]#

I'm not sure I know what I was supposted to do with these, but I am not sure where the link settings for the sm-client are from here. But I may just be ignorant of the obvious commands that are possible, so please fill me in if there are any. I also cannot locate it as a service or run service commands with it either. Is there a special way that sm-client has to be run? I looked for a man page on it....none found.



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