Question about notifications

Jeppe_Nejsum_Madsen · 2015-07-23 21:55:30 UTC

Hi,

Besides a few outstanding issues (ruby 1.8.7 doesn’t seem to work and
this http://tickets.opscode.com/browse/CHEF-269), I’ve got my EC2
setup going, mostly thanks to the excellent documentation and examples.

So, next step is to try to speed up my recipes and I’m running into a
few areas where I don’t think I fully understand how things are
supposed to work:

Given this recipe

remote_file “war” do
path "/usr/share/jetty6/webapps/ROOT.war"
owner "jetty"
mode 0640
source node[:war]
notifies :restart, resources(:service => “jetty6”)
end

I would assume Chef would either a) Start the jetty6 service if it was
not running or b) restart the jetty6 service if it was running already
And only do this if the remote file has changed.

First it seems that, if the service is not running already, it is not
started??

[Thu, 11 Jun 2009 20:43:37 +0200] DEBUG: remote_file[fz_war] changed
from f18463d301b65a6c161669d0de190293f78480b3ed88590215ea30947cf8dfbf
to 1792af24a3aa7829dbf15340ad54d7a7af9db272fa769e4572f03e783c4c3da5
[Thu, 11 Jun 2009 20:43:37 +0200] INFO: Updating remote_file[fz_war]
at /usr/share/jetty6/webapps/ROOT.war
[Thu, 11 Jun 2009 20:43:37 +0200] INFO: Backing up remote_file[fz_war]
to /usr/share/jetty6/webapps/ROOT.war.chef-20090611204337
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: Removing backup of
remote_file[fz_war] at /usr/share/jetty6/webapps/
ROOT.war.chef-20090611181740
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: false
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: Chef Run complete in 24.356492
seconds

If the service is already running it is restarted ok:

[Thu, 11 Jun 2009 20:53:46 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: true
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: attempting
to restart
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: Executing /etc/init.d/jetty6
restart
[Thu, 11 Jun 2009 20:54:28 +0200] DEBUG: ---- Begin output of /etc/
init.d/jetty6 restart ----

Second, it seems that the notification always takes place, even if the
remote file didn’t change:

Thu, 11 Jun 2009 20:44:35 +0200] DEBUG: /fz-1.war 100% done (9736249
of 9736249)
[Thu, 11 Jun 2009 20:44:36 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: false
[Thu, 11 Jun 2009 20:44:36 +0200] INFO: Chef Run complete in 23.318144
seconds

Did I misunderstand something about how notification & services are
supposed to work??

Given this recipe:

service “mountec2vol” do
supports :status => true, :restart => true
action [ :enable, :start ]
end

It seems Chef is running the “status” command twice. Is this necessary?

[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: Processing service[mountec2vol]
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: service[mountec2vol] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: service[mountec2vol] supports
status, running
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: Executing /etc/init.d/
mountec2vol status
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: ---- Begin output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: STDOUT: ATTACHMENT
vol-98f316f1 i-8b4f4cff /dev/sdh attache2009-06-11T13:33:56+0000
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: STDERR:
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: ---- End output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: Ran /etc/init.d/mountec2vol
status returned 0
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol]: not
enabling, already enabled
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol] supports
status, running
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: Executing /etc/init.d/
mountec2vol status
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: ---- Begin output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: STDOUT: ATTACHMENT
vol-98f316f1 i-8b4f4cff /dev/sdh attache2009-06-11T13:33:56+0000
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: STDERR:
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: ---- End output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: Ran /etc/init.d/mountec2vol
status returned 0
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: service[mountec2vol]: not
starting, already running

/Jeppe

Arjuna_Christensen · 2015-07-23 22:11:07 UTC

On 12/06/2009, at 6:56 AM, Jeppe Nejsum Madsen wrote:

Hi,

Besides a few outstanding issues (ruby 1.8.7 doesn’t seem to work
and this http://tickets.opscode.com/browse/CHEF-269), I’ve got my
EC2 setup going, mostly thanks to the excellent documentation and
examples.

So, next step is to try to speed up my recipes and I’m running into
a few areas where I don’t think I fully understand how things are
supposed to work:

Given this recipe

remote_file “war” do
path "/usr/share/jetty6/webapps/ROOT.war"
owner "jetty"
mode 0640
source node[:war]
notifies :restart, resources(:service => “jetty6”)
end

I would assume Chef would either a) Start the jetty6 service if it
was not running or b) restart the jetty6 service if it was running
already
And only do this if the remote file has changed.

Restart only fires if the service is currently running - sorry for
pasting this code in line, but it helps me illustrate.

   def action_restart
     if @current_resource.running
       Chef::Log.debug("#{@new_resource}: attempting to restart")
       status = restart_service()
       if status
         Chef::Log.info("#{@new_resource}: restarted successfully")
       end
     end
   end

If the service is actually running, in priority, the following things
are checked:

If the resource has a ‘restart_command’ parameter set, run that.
If the resource supports :restart, i.e.; through “supports
[ :status, :restart ]”
Otherwise just stop, sleep, then start the service again.

def restart_service
if @new_resource.restart_command
run_command(:command => @new_resource.restart_command)
elsif @new_resource.supports[:restart]
run_command(:command => “#{@init_command} restart”)
else
stop_service
sleep 1
start_service
end
end

First it seems that, if the service is not running already, it is
not started??

[Thu, 11 Jun 2009 20:43:37 +0200] DEBUG: remote_file[fz_war] changed
from
f18463d301b65a6c161669d0de190293f78480b3ed88590215ea30947cf8dfbf to
1792af24a3aa7829dbf15340ad54d7a7af9db272fa769e4572f03e783c4c3da5
[Thu, 11 Jun 2009 20:43:37 +0200] INFO: Updating remote_file[fz_war]
at /usr/share/jetty6/webapps/ROOT.war
[Thu, 11 Jun 2009 20:43:37 +0200] INFO: Backing up
remote_file[fz_war] to /usr/share/jetty6/webapps/
ROOT.war.chef-20090611204337
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: Removing backup of
remote_file[fz_war] at /usr/share/jetty6/webapps/
ROOT.war.chef-20090611181740
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:43:38 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: false
[Thu, 11 Jun 2009 20:43:38 +0200] INFO: Chef Run complete in
24.356492 seconds

If the service is already running it is restarted ok:

[Thu, 11 Jun 2009 20:53:46 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: true
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: service[jetty6]: attempting
to restart
[Thu, 11 Jun 2009 20:53:46 +0200] DEBUG: Executing /etc/init.d/
jetty6 restart
[Thu, 11 Jun 2009 20:54:28 +0200] DEBUG: ---- Begin output of /etc/
init.d/jetty6 restart ----

Second, it seems that the notification always takes place, even if
the remote file didn’t change:

A notification should only be triggered if the resource in question
actually changed. Are you certain that the file is not being updated
every time?

Thu, 11 Jun 2009 20:44:35 +0200] DEBUG: /fz-1.war 100% done (9736249
of 9736249)
[Thu, 11 Jun 2009 20:44:36 +0200] INFO: remote_file[fz_war] sending
restart action to service[jetty6] (delayed)
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6] does not
support status and you have not specified a status command, falling
back to process table inspection
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6]: attempting
to match jetty6 ((?-mix:jetty6)) against process table
[Thu, 11 Jun 2009 20:44:36 +0200] DEBUG: service[jetty6]: ps -ef
exited and parsed successfully, process running: false
[Thu, 11 Jun 2009 20:44:36 +0200] INFO: Chef Run complete in
23.318144 seconds

Did I misunderstand something about how notification & services are
supposed to work??

Given this recipe:

service “mountec2vol” do
supports :status => true, :restart => true
action [ :enable, :start ]
end

It seems Chef is running the “status” command twice. Is this
necessary?

This isn’t something I’ve encountered, but I’ll look into it. Looks
like possibly the two actions are causing the provider to reload.

[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: Processing
service[mountec2vol]
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: service[mountec2vol] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: service[mountec2vol]
supports status, running
[Thu, 11 Jun 2009 16:41:52 +0200] DEBUG: Executing /etc/init.d/
mountec2vol status
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: ---- Begin output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: STDOUT: ATTACHMENT
vol-98f316f1 i-8b4f4cff /dev/sdh attache2009-06-11T13:33:56+0000
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: STDERR:
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: ---- End output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: Ran /etc/init.d/mountec2vol
status returned 0
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol]: not
enabling, already enabled
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol] using
Chef::Provider::Service::Debian
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: service[mountec2vol]
supports status, running
[Thu, 11 Jun 2009 16:42:00 +0200] DEBUG: Executing /etc/init.d/
mountec2vol status
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: ---- Begin output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: STDOUT: ATTACHMENT
vol-98f316f1 i-8b4f4cff /dev/sdh attache2009-06-11T13:33:56+0000
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: STDERR:
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: ---- End output of /etc/
init.d/mountec2vol status ----
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: Ran /etc/init.d/mountec2vol
status returned 0
[Thu, 11 Jun 2009 16:42:08 +0200] DEBUG: service[mountec2vol]: not
starting, already running

Thanks!

–
AJ Christensen, Software Engineer
Opscode, Inc.
E: aj@opscode.com

Arjuna_Christensen · 2015-07-23 22:11:08 UTC

On 12/06/2009, at 6:56 AM, Jeppe Nejsum Madsen wrote:

Hi,

Besides a few outstanding issues (ruby 1.8.7 doesn’t seem to work
and this http://tickets.opscode.com/browse/CHEF-269), I’ve got my
EC2 setup going, mostly thanks to the excellent documentation and
examples.

So, next step is to try to speed up my recipes and I’m running into
a few areas where I don’t think I fully understand how things are
supposed to work:

Given this recipe

remote_file “war” do
path "/usr/share/jetty6/webapps/ROOT.war"
owner "jetty"
mode 0640
source node[:war]
notifies :restart, resources(:service => “jetty6”)
end

I would assume Chef would either a) Start the jetty6 service if it
was not running or b) restart the jetty6 service if it was running
already
And only do this if the remote file has changed.

[snip]

After a little internal discussion, I’ve opened http://tickets.opscode.com/browse/CHEF-361
and marked it for 0.7.2 which is due in two weeks.

“Init service provider currently doesn’t start a service when the
’restart’ action is called if the service is not already running.”

–
AJ Christensen, Software Engineer
Opscode, Inc.
E: aj@opscode.com

Jeppe_Nejsum_Madsen · 2015-07-23 22:11:08 UTC

On 11 Jun 2009, Arjuna Christensen wrote:

Restart only fires if the service is currently running - sorry for
pasting this code in line, but it helps me illustrate.

ok, that (sort of makes sense then. Is there a way to accomplish
what I need: start if stopped, restart if started?

The only thing I could think of was to stop and then start, but hey if
I can shave some time off the running time I’m all ears

Ahhh just saw your next reply about CHEF-361. Sweet! (Just in case you
forgot, the fix for CHEF-269 is probably less than 5 min

Second, it seems that the notification always takes place, even if
the remote file didn’t change:

A notification should only be triggered if the resource in question
actually changed. Are you certain that the file is not being updated
every time?

In this case, yes. What was missing from the log entries was a log entry
I inserted just after the checksums were compared and found equal. Also
note how the log entries doesn’t contain anything between the 100% entry
and the restart entry.

/Jeppe