How to enable/disable OS X beta participation from Terminal?
As mentioned by SeanCLT, you/your system needs to be enrolled in one of the programs and you need to have the right utilities installed The statement about the utilities is an assumption, I have not tried it without. After that you can use the softwareupdate command to enable and disable the beta/pre-release source.
You can disable it via:
softwareupdate --clear-catalog
Enabling is a bit more tricky, because you need to choose your channel/source. The options are:
OS X Public Beta
sudo softwareupdate --set-catalog https://swscan.apple.com/content/catalogs/others/index-10.12beta-10.12-10.11-10.10-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
OS X Developer Beta catalog
sudo softwareupdate --set-catalog https://swscan.apple.com/content/catalogs/others/index-10.12seed-10.12-10.11-10.10-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
OS X Gold Master catalog
sudo softwareupdate --set-catalog https://swscan.apple.com/content/catalogs/others/index-10.12-10.11-10.10-10.9-mountainlion-lion-snowleopard-leopard.merged-1.sucatalog.gz
Steps to Enroll into Beta
- Go to https://beta.apple.com/sp/betaprogram/guide
- Sign in with your Apple ID
- Click Enroll Your Devices on top right menu bar
- Step 2 has a blue button "Download the OS X EL Capitan Public Beta Access Utility"
I was also enrolled into beta on my VM i recently unenrolled it after 10.11.4 release
you might find this question useful How to move from beta to stable releases of OS X