Can I install plesk on the lamp appliance ? If so how ? From the screenshot of webmin this looks like ubuntu 8.04 if so can I use apt-get ?
As you say, TKL is an ubuntu 8.04 (and soon 10.04) appliance. It just that you won't have any benefits from installing in the TKL instead of a clean system Ubuntu Server System.
Being propietary software, you should go with the company's support for installing. I don't know plesk but it should have a bundle package with included apache/php or something like that.
My 2 cents...
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