ability to import initial guest datasets

[liyu1981]

Currently DogeOS relies on network importing the guest datasets for using.

To provide ability to import some initial guest datasets:

1. includes: smartmachine-base, centos, ubuntu and freebsd
2. can import in offline mode

[Licenser]

I feel not good about that idea, it would increse the size of the boot image by over a gigabyte. Having base64 should be enough to get people started, from there on only the FiFo zone needs internet access to import datasets so the hypervisors can stay nice and isolated.

[liyu1981]

yes, you are right. But there are some reasons ...

1. I really care about the installation when there is no internet access. Just remember old Windows system, or some live linux system, they do not need anything to be practically functional. Therefore a good cloud OS should also be able to provide practical functions, and some guest datasets are part of things towards that goal.
2. The sizes will increase. Yes, that's very right. For the most recent progress, I have managed to make the next version DogeOS with 0.4.4 version FiFo to be around 650MB. If add some datasets, for what I have calculated, will be < 2GB.
3. The technique I used in offline installing the necessary packages of FiFo zone, will be used again for the default datasets. That is, still keep a very small footprint of the OS, but a removable part will be mounted when it is needed.
4. May be I can just populate multiple versions of DogeOS in future, they are

1. Minimal version, no default datasets at all.
2. Medium version, with only a smartmachine base as default datasets.
3. Full version, with all I have mentioned (and even with some Windows versions).

Multiple versions will give the users choices. When some intranet admin want to try DogeOS (as well as FiFo), and he have no intend to break any intranet network policies, he can use either medium or full version (just like CentOS, there is a full DVD image). The medium or full version will enable him to experience DogeOS without any pain to configure more network. With that smooth installation and experience, he should build some trust against our OS, and then he can be a long-term user.

I think in next milestone, after I finish the auto-build scripts for DogeOS, the above goals can be achieved.

[Licenser]

I like the idea of having multiple versions, for a long run something like 'build your own dodge' could be fun, i.e. when downloading users can decide which datasets they want.

My main concern is PXE, since I think for PXE booting a image it is required to load the entire thing in the memory not only the active part (but I could be mistaken here), so a 2G image PXE booted would mean 2G of memory lost on each hypervisor which would hurt.

[liyu1981]

For memo:

for nginx, the default client_max_body_size is too small.

to enable uploading, nginx setting should adjust to

client_max_body_size 10240M;