How are the source files used in freebsd-update created?

[JamesElstone]

As the title says, when using freebsd-update fetch how are the source files it downloads created? Is this documented somewhere I have missed please?

The reason I ask is that the freebsd-udpate command allows for an alternative source / server, so was looking to generate the source files rather than downloading it multiple times.

Kind regards,
James

 

[cy@]

It will not create source files if none already exist.

 

[covacat]

bsdiff ?

 

[SirDice]

Build Your Own FreeBSD Update Server

Building your own freebsd-update server allows a system administrator to perform fast updates for a number of machines from a local mirror

docs.freebsd.org