GitLab email notifications not sending - email

Question

I just recently install GitLab v5.0 on an Ubuntu 12.04 server and am now having issues with email notifications. I can't get GitLab to send any emails of any kind.
I've got my config/environments/production.rb file setup to use sendmail as the transport service:
config.action_mailer.delivery_method = :sendmail
config.action_mailer.perform_deliveries = true
config.action_mailer.raise_delivery_errors = true
And I can manually use sendmail successfully from the shell as described here: http://scratching.psybermonkey.net/2011/03/sendmail-how-to-test-sending-email.html
My config/gitlab.yml file is setup with the following email setting:
email_from: gitlab#myops.com
I've read that it could be a problem with Sidekiq not running so I ran the following command but nothing has changed.. I still can't send emails:
$ sudo -u git -H bundle exec rake sidekiq:start RAILS_ENV=production
$ ps aux |grep -i sidekiq
git 2791 2.1 4.2 206476 86620 pts/0 Sl 14:45 0:23 sidekiq 2.7.5 gitlab [0 of 25 busy]
Which indicates to me that Sidekiq is indeed running... what else could be the issue here? There doesn't seem to be much documentation on GitLab's wiki regarding email settings unfortunately...
I found the following error being logged in sidekiq.log:
2013-04-24T21:09:01Z 2791 TID-1jaur8 Sidekiq::Extensions::DelayedMailer JID-21bd3ec0f086351088992396 INFO: start
2013-04-24T21:09:01Z 2791 TID-1jaur8 Sidekiq::Extensions::DelayedMailer JID-21bd3ec0f086351088992396 INFO: fail: 0.004 sec
2013-04-24T21:09:01Z 2791 TID-1jaur8 WARN: {"retry"=>true, "queue"=>"default", "timeout"=>30, "class"=>"Sidekiq::Extensions::DelayedMailer", "args"=>["---\n- !ruby/class 'Notify'\n- :new_user_email\n- - 4\n - pSzzULp8\n"], "at"=>1366819034.5969028, "jid"=>"21bd3ec0f086351088992396", "error_message"=>"Couldn't find User with id=4", "error_class"=>"ActiveRecord::RecordNotFound", "failed_at"=>"2013-04-24T15:57:19Z", "retry_count"=>10, "retried_at"=>2013-04-24 21:09:01 UTC}
2013-04-24T21:09:01Z 2791 TID-1jaur8 WARN: Couldn't find User with id=4
2013-04-24T21:09:01Z 2791 TID-1jaur8 WARN: /home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/relation/finder_methods.rb:343:in `find_one'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/relation/finder_methods.rb:314:in `find_with_ids'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/relation/finder_methods.rb:107:in `find'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/activerecord-3.2.13/lib/active_record/querying.rb:5:in `find'
/home/git/gitlab/app/mailers/notify.rb:23:in `new_user_email'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/abstract_controller/base.rb:167:in `process_action'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/abstract_controller/base.rb:121:in `process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionpack-3.2.13/lib/abstract_controller/rendering.rb:45:in `process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionmailer-3.2.13/lib/action_mailer/base.rb:459:in `process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionmailer-3.2.13/lib/action_mailer/base.rb:453:in `initialize'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionmailer-3.2.13/lib/action_mailer/base.rb:439:in `new'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/actionmailer-3.2.13/lib/action_mailer/base.rb:439:in `method_missing'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/extensions/action_mailer.rb:20:in `perform'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/processor.rb:45:in `block (3 levels) in process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:109:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:109:in `block in invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/timeout.rb:11:in `block in call'
/usr/local/lib/ruby/1.9.1/timeout.rb:68:in `timeout'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/timeout.rb:10:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:111:in `block in invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/active_record.rb:6:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:111:in `block in invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/retry_jobs.rb:49:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:111:in `block in invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/logging.rb:11:in `block in call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/logging.rb:22:in `with_context'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/server/logging.rb:7:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:111:in `block in invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:114:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/middleware/chain.rb:114:in `invoke'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/processor.rb:44:in `block (2 levels) in process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/processor.rb:80:in `stats'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/sidekiq-2.7.5/lib/sidekiq/processor.rb:43:in `block in process'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/calls.rb:23:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/calls.rb:23:in `public_send'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/calls.rb:23:in `dispatch'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/future.rb:18:in `block in initialize'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/internal_pool.rb:48:in `call'
/home/git/gitlab/vendor/bundle/ruby/1.9.1/gems/celluloid-0.12.4/lib/celluloid/internal_pool.rb:48:in `block in create'
Any ideas?

Answer 1

This is my entries at the end in /config/environment/production.rb and that is working for me.
Comment out sendmail options and use external SMTP relays
##config.action_mailer.delivery_method = :sendmail ## Comment out this
# Defaults to:
## config.action_mailer.sendmail_settings = {
## :location => '/usr/sbin/sendmail',
## :arguments => '-i -t'
## }
config.action_mailer.perform_deliveries = true
config.action_mailer.raise_delivery_errors = true
## SMTP Settings
config.action_mailer.delivery_method = :smtp
config.action_mailer.smtp_settings = {
:address => '10.146.10.90', ## My SMTP Relay/Gateway
:port => 25, ## SMTP Port
:domain => 'gitlab.example.com', ## My Domain
:authentication => :plain, ## Let it be plain as it is inside my LAN
##:user_name => 'gitlab#yourserver.com', ## This is not required as long as
##:password => 'yourPassword', ## SMTP Gateway allows anonymous relay
##:enable_starttls_auto => true ## In LAN
##:user_name => '',
##:password => '',
:enable_starttls_auto => true
}
end

Answer 2

On CentOS, this helped for me:
check your file /home/git/gitlab/config/environments/production.rb (if your running on production, wich is standard)
There you can change your sendmail settings. You should try to remove the -t parameter, wich fixed it for me! Some mailservers don't accept this parameter (check your maillog to be sure)
config.action_mailer.sendmail_settings = {
:location => '/usr/sbin/sendmail',
:arguments => '-i'
}