Cant send mail using exim/sendmail

Not knowing anything about exim, some ideas:

1. Is /usr/bin/sendmail linked to exim? If you have fooled around with installing different MTAs, it may not be.

2. What do your mail logs say?

3. Can you successfully invoke /usr/sbin/sendmail from the command line? Like so:

$ /usr/sbin/sendmail -t -i
To: me@example.net
From: me@myexamplelinode.com
Subject: a test

this is a test
^D

4. If #3 works, can you also do it as the user that is having trouble sending mail (e.g., on Debian/Ubuntu, Apache runs as the www-data user)?

5. Your hosts file almost certainly has nothing to do with things.

Hi,

Thanks for the reply.

Yes , sendmail is linked to exim(Wrapper) . Iam able to send mails using sendmail -t -i < mail.txt

Like i said the mails work sometimes(for all the users). And suddenly it stops . I have to restart httpd,exim to make it work . and most of the times the exim crashes and i ahve to manually start again .

I was thinking on cron restarting all the services every hour or so .. But that doesnt sound right.

@Sheshadri:

I have to restart httpd,exim to make it work . and most of the times the exim crashes and i ahve to manually start again .
What's happening to the rest of your server – are you sure you're not just OOMing with a misconfigured apache or my.cnf ? Exim is generally rock stable.

What distribution are you using? http://library.linode.com/email-guides/exim/ is helpful if you're using a debian based distro.

What program are using to test exim4?

echo "Body" | mail -s "Subject" you@domain.com