Rotating logs in Rails 3

Rails
1

It looks like there are two accepted ways of rotating log files on
production, but most of the discussion I’ve found is a couple years
old. Does anyone have an opinion on which of these methods is better
for a Rails 3 app on CentOS? Which method are you using and what are
the drawbacks of it?

  1. Inside of Rails:

In config/environments/production.rb, put in something like this line:

config.logger = Logger.new(config.log_path, 50, 1.megabyte)

  1. Using logrotate:

create the file /etc/logrotate.d/passenger and put something like this
in it:

/home/deploy/app/shared/log/*.log {
daily
missingok
rotate 30
compress
delaycompress
sharedscripts
postrotate
touch /home/deploy/app/current/tmp/restart.txt
endscript
}

Thanks!

2

Okay, I’ll bite and give my $0.02.

Method #1 Pros and Cons:

Con: I don’t like the application code to be responsible for log
rotations.
It “feels” like this should be a system administrative task.
Pro: Easy to set up and no need to drop a logrotate config in /etc on
deployment

Method #2

Con: Deployment requires another “external” step (configuration external
to
the application code itself)
Pro: From a sysadmin point of view, I keep all my “log rotation”
configuration in one place (as it ought to be).

My Preference

Method #2: use capistrano or other scripted/automated deployment tool to
drop (or update) a logrotate config in your /etc/logrotate.d/ directory
to
overcome the downside of this method and you’re golden.

That’s just my opinion. I’d also be interested in other points of view
and
better ideas.

3

Okay, I’ll bite and give my $0.02.

Method #1 Pros and Cons:

Con: I don’t like the application code to be responsible for log rotations. It
“feels” like this should be a system administrative task.
Pro: Easy to set up and no need to drop a logrotate config in /etc on deployment

Agreed…

Method #2

Con: Deployment requires another “external” step (configuration external to the
application code itself)
Pro: From a sysadmin point of view, I keep all my “log rotation” configuration
in one place (as it ought to be).

My Preference

Method #2: use capistrano or other scripted/automated deployment tool to drop
(or update) a logrotate config in your /etc/logrotate.d/ directory to overcome the
downside of this method and you’re golden.

One drawback to this is /etc/logrotate.d is usually owned by root… do
you want capistrano to be able to write to root protected directories?
That opens a door for someone to put in a postrotate script that does
all kind of nasty things as root :frowning:

If it was me, I’d install a rails logrotate file once that covered all
your deployed applications… something like the below. This way it’s
installed once, and never needs to be installed again for any new
applications. As long as you make sure the regex’s match all your apps
anyway :slight_smile:

/home/philip/apps//shared/log/.log {
daily
missingok
rotate 30
compress
delaycompress
notifempty
create 640 philip philip
sharedscripts
postrotate
if [ -f “. /etc/apache2/envvars ; echo ${APACHE_PID_FILE:-/var/run/apache2.pid}” ]; then
/etc/init.d/apache2 reload > /dev/null
fi
endscript
}

4

It seems like the consensus is to use logrotate and handle this
completely outside of rails. I tried that yesterday and it worked very
easily, so I don’t see any point to using the rails method. Using the
wildcard inside the path was one thing I didn’t think of. I thought
that I’d have to remember to change the logrotate file for every new
app I deploy, but since they follow a pattern, I can say:

/home/username/www/*/log/production.log

And it gets them all.

So I just put this in my instructions with the steps for setting up a
new server and forget about it.

Thanks!