How can I keep the downloaded packeges and updates?

When you install a software using Yast, it downloads, installs and removes the package. Now how can I keep the downloaded packages?
In fedora it’s possible by editing

/etc/yum.conf

and changing keepcache=0 to keepcache=1

zypper modifyrepo -k --all

Ok TNX.
Now can you tell me how can I make a local repository with the downloaded packages? I mean is there any software to do that like “AptOnCD” in Ubuntu or any command like “createrepo” in Fedora?
I want to burn it on a DVD and install the packeges on 3 other PCs. I dont want to download the same packeges 4 times!

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