Tiny Deathstars of Foulness

The Caching Server in OS X Server 5 (for El Capitan and Yosemite) now does content and Software Updates. Woohoo, the promised land. Now, when 10 of your users download that latest Nicholas Sparks book and movie, you only sacrifice your WAN pipe to download it once, and the other 9 people piggy-back off that. And when OS X El Capitan ships, you only need to download it over the WAN once, and the other local users will pull off that spiffy Caching Server sitting in your office. Pretty sweet, right?

So, how do you use this ultra-complicated service. Well, it looks and feels kinda’ like an iPad app. Which is to say that as far as server stuffs go, this thing is pretty darn easy to use. To get started, open the Server app and then click on the Caching service in the sidebar of the Server app.

Screen Shot 2015-09-10 at 10.49.00 PM

Here, click on the ON button. OMG, so hard. But wait, there’s more! Click on that Change Location button and you can select a larger volume for your updates that are cached. You’ll likely wanna’ do this because the entire series of OZ is kinda’ big (and yes, creepy, but really well written)…

Screen Shot 2015-09-10 at 10.50.21 PM

If you do change the location, you’ll see a window to change the volume you’re caching to. That’s pretty much it. Other than the waiting for the updates to move. By default, the Caching service allows for unlimited space. Use the spiffy slider to reduce the total amount of space that the service can occupy on the hard drive. This can be a good thing if it happens to be your boot volume and there are other more mission critical services hosted on that thing.

Screen Shot 2015-09-10 at 10.54.04 PM

Overall, this all seems pretty straight forward. So what else might you need to know. In case you get a corrupt asset, or in case your volume fills up, there’s a Reset button, to reset the cache.

Screen Shot 2015-09-10 at 10.53.04 PM

The service can be controlled from the command line as well. To start it, use the serveradmin command along with the start verb and the service name (oddly, that’s caching).

sudo /Applications/ start caching

To stop the service, use the stop verb along with the service name:

sudo /Applications/ stop caching

To see a list of settings, use the settings verb with the service name:

sudo /Applications/ settings caching

The settings are as follows, mostly available in the Server app:

caching:ReservedVolumeSpace = 25000000000
caching:CacheLimit = 350000000000
caching:ServerRoot = "/Library/Server"
caching:ServerGUID = "DEE63BBB-9F32-428B-B717-E3941F82E2DC"
caching:DataPath = "/Library/Server/Caching/Data"
caching:LocalSubnetsOnly = yes
caching:Port = 0

One setting you might choose to change is the reserved volume space, as this can keep you from getting the service started on smaller volumes. In the above example, the setting is 250 gigs. To change that to 100 gigs:

sudo /Applications/ settings caching:ReservedVolumeSpace = 10000000000

September 20th, 2015

Posted In: Mac OS X, Mac OS X Server, Mac Security, Mass Deployment

Tags: , , , , , , , ,

  • Jerry Polyak

    I’m using it, I’m using it. You’re such a nag.

  • sashk

    Do you know of any way to limiting bandwidth used by caching server? Recently, Apple’s CDNs became so good, that they fill up whole bandwidth it can fill up when downloading an update, and this causing troubles. Adding line conditioning is not what I want to do though, as I have single server with single ethernet connection and want to avoid limiting time machine bandwidth as well.. Any input will be appreciated – thank you.

  • Kheenan Halvorson

    So i am doing this but need to get the DNS records so i can edit our DNS entry’s so the macs point at my server rather than apple’s. I use to click on a button called client configuration to get these. The help files also say that but I do not see that button anywhere. Where did it go?