If your nic supports WOL, it probably needs to be enabled in your computers BIOS first.

Most WOL tools use the “MagicPacket(tm)” method, so the right command to enable it on the nic “eth0″ would be

ethtool -s eth0 wol g

This is not a persistent setting and it is gone after a reboot. Most tips around recommend creating a runlevel script for executing this command after boot or before shutdown.

I’ve added the command as a hook in my network scripts:

auto eth0
iface eth0 inet dhcp
        pre-down ethtool -s eth0 wol g

You can also use post-up. I like this method because i tend to forget about my runlevel scripts and so i keep the network stuff in one place

If you are a debian user, you maybe need to stop your system from turning off the nic on HALT. To do so, add

NETDOWN=no

to “/etc/default/halt”.

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module ActionView
  module Helpers #:nodoc:
    module AssetTagHelper
      def image_path(source)
        compute_public_path(source, 'static_images')
      end
      alias_method :path_to_image, :image_path # aliased to avoid conflicts with an image_path named route
    end
  end
end

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To revert a complete working copy or a single file use:

svn merge -rHEAD:PREV .
# or
svn merge -rHEAD:PREV path/to/file
svn commit -m "reverted"

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Smart spawning of Passenger processes creates shared file descriptors. As the connections to memcached are sockets they are shared as well so data on them gets corrupted which is explained very nicely in the Passenger documentation: Example 1: Memcached connection sharing (harmful).

The solution presented there works like a charm. The reestablish_connection_to_memcached line is actually not more than CACHE.reset where CACHE is the reference to the memcache connection.

After that change, spawning methods smart-lv2 and smart will work in connection with environment.rb configured memcache connections.

Edit: As requested in the comments, a little example:

memcache_options = {
  :c_threshold => 10000,
  :compression => true,
  :debug => false,
  :namespace => 'some_ns',
  :readonly => false,
  :urlencode => false
}
 
CACHE = MemCache.new memcache_options
CACHE.servers = '127.0.0.1:11211'
begin
   PhusionPassenger.on_event(:starting_worker_process) do |forked|
     if forked
       # We're in smart spawning mode, so...
       # Close duplicated memcached connections - they will open themselves
       CACHE.reset
     end
   end
# In case you're not running under Passenger (i.e. devmode with mongrel)
rescue NameError => error
end

In this case, CACHE is the global constant that i use to access my memcache-client.

I guess you’ll need to do the same with the global Rails.cache object, but i’m not sure. Anyway, the above solution works for me.

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It seems, that passengers spawn method “smart” isn’t compatible with memcached. Within seconds on a lightly loaded server the cache gets corrupted big time.

I got better results with a newer memcache client (the ruby gem actually), but for that i need to remove the client from the rails vendor lib. Furthermore, under higher load there still where errors.

Only solution is to set the spawn method to conservative like so

RailsSpawnMethod conservative

Problem seems to be known in the Phusion and Rails teams.

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Time.now.xmlschema

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# Turn it off for just some columns
class Picture < ActiveRecord::Base
 def self.skip_time_zone_conversion_for_attributes
   [:created_at, :published_at]
 end
end
 
# Turin it off for the whole model
class Picture < ActiveRecord::Base
 def self.time_zone_aware_attributes
   false
 end
end

Thanks a lot!

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Menü, #, 4th Tab, 5

(On a german phone: “Einstellungen / Anrufe / Zeit und Kosten”)

I guess that works with other SEs like K800i and K850i.

I remember an old SE that i had which always displayed the traffic after ending an internet session, i wonder why they changed it.

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The “Click through” property on both Apples X11 and the X11 provided by XQuartz is not set. This leads to the fact, that you have to click on each X11 window twice: First activating it, 2nd pushing a button or whatever else. I hate this, i really do.

With Apples X11, open a terminal and enter:

defaults write com.apple.X11 wm_click_through -bool true

With XQuartz X11 enter:

defaults write org.x.X11 wm_click_through -bool true

This will help you with all X11 apps, like Gimp, Inkscape, Open Office and the likes.

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As i do not have Apple Remote Desktop or any other VNC server enabled on my Macbook, i do have a problem.

I can vpn into my home and i can ssh into the Macbook, so i came up with the following solution:

Put the following three lines into a plain textfile, i.e. “sleep.txt” and save it somewhere:

tell application "Finder"
  sleep
end tell

Then, open Terminal.app, change to the directory you saved the file in and execute:

osascript sleep.txt

Your ssh connection will then timeout and the Mac sleeps.

Stupid me forgot that ssh can execute remote commands: From your workmachine execute

ssh my_home_computer 'osascript sleep.txt'

and you’re done. Thanks “tante” for reminding me

Alternatively, you can achieve similar with Mail.app itself, have a look at the solution here, but i like mine better.

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