New user here.
Is there a system that i can install a Turnkey base (maybe JeOS) and then install one or more turnkey services/applicance in the same system ?
Short answer: No. The way TKL is designed is that each server has its own specific function and purpose and that's all it does. It is designed so that it all works out of the box with minimal config by the end user required. Whilst what you (and many before you) are asking for is potentially possible, it creates a whole new level of complexity and potential for breakage and bugs. So TKL does not officially support such a scenario.
Long answer #1: Yes, by use of a hypervisor OS. If you wish to have a number of services/applications running on the same hardware then I strongly suggest a hypervisor OS (such as my personal favourite: ProxmoxVE) and then install the various servers as VMs. The advantages of this setup are numerous and the disadvantages minimal (IMO redundancy is really the only disadvantage and in many scenarios its actually an advantage). My current server is an old desktop with a 4yo Core2Duo (E6400 I think from memory) and all I did is add a heap of RAM (8GB of generic DDR2) and I have ~20 VMs on it. Right ATM 11 of them are running (although not under much load) and using about 4% CPU and ~2.8GB RAM. Almost all of those are TKL servers but I have a Win XP (SP3) VM which is allocated only 1 CPU & 512MB RAM and it performs pretty much as you'd expect XP SP3 to run on that (ok but a little sluggish). Bottom line, unless your server is going to get hit with heaps of traffic, or run particularly intensive apps (such as BigBlueButton) it is probably wasting your hardware to run a single Linux Server OS on any PC built within the last few years.
Long answer #2: Yes but its going to take lots of work. You are more than welcome to play with TKL and set it up however you want. It is Open Source after all and that's what its meant for! TKL v11.0RC is based on Ubuntu Lucid/10.04 server (the older but stable TKL 2009.10-2 is based on Ubuntu Hardy/8.04 server) and basically anything you can do on Ubuntu server, you can do on TKL. There are a number of community created patches (TKLPatches) that you can use to patch the TKL OS to create a particular appliance. It is untested, but you could try selecting on appliance and patching it with the patch of another appliance. Unfortunately this only applies to community submitted patches, all current TKL appliances do not have patches. You will find some threads here on the forum where others have added extra functionality (with mixed success) to TKL appliances such as using WordPress and Moodle appliances to also serve standard html web content. Otherwise you're somewhat on your own.
Last word: If you set out clearly what you are trying to do, myself and other community members may be able to give some guidance and ideas to acheive your ends. However expect to get your hands dirty and if your experience with Linux is limited, the learning curve will be steep! Perhaps let us know what you want to do and we can go from there?
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