There is no upgrade path between 5.6 and 6.0 you have to build a new server and copy your files over.

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I have just done the upgrade, this is true.

Yeah, but I was wondering more about how you copied the files from server to server and such...

I have a partition where I store my services and my website file,
that partition can be copied painless by using the clone funtionalities from linode manager.

The configuration file must be copied manually or using ssh GET or SCP if you need to transfer directory.
With SCP I transferred directories at lighting fast speed from my linode to my second linode because the two nodes are on the same datacenter.
You know, there are many ways to transfer files between servers.

Software must be obviously reinstalled from scratch but yum + epel is your friend.
Pay much attention to the mirror priorities, epel is really unkind with other repos.

rsync is a good tool for copying files between servers, also you can assign your old and new linode internal ips if they're in the same dc which won't use your bandwidth.

_________________
Paid support
How to ask for help
1. Give details of your problem
2. Post any errors
3. Post relevant logs.
4. Don't hide details i.e. your domain, it just makes things harder
5. Be polite or you'll be eaten by a grue