Permission denied in tmp

You probably didn't create your Rails application with the user running the server now. Can you paste the output of ls -alh /srv/www/appname/tmp/cache/assets and tell us the user running the webserver ?

1. Make the tmp folder of your project writable:

   chown -R group:user /path/to/rails/app/tmp
   chmod -R 777 /path/to/rails/app/tmp
   

2. In your console, run rake tmp:cache:clear

3. Restart your application.

If the user:group running your web server is http:http and it's running on *nix, do this:

sudo chown -R http:http /srv/www/appname/

Also, silly question, but does /tmp/cache/assets exist?

And, if so, as @leonel points out, you may also need to change the permissions:

chmod 777 /srv/www/appname/tmp/cache

Be careful setting 777 permissions on anything. Only do this to verify a permissions issue, then reset to the most minimal permissions necessary.

Most likely you're running your app under apache passenger.

You have to change the owner of config/environment.rb to somebody who has permissions to your app's folder.

chown -R www-data:www-data /path/to/app