04 · Recreating a mucua: the same baobab in another ground

The baobab that falls leaves seeds. But sometimes we want the same baobab back, with the same name.

When

The mucua's disk died. The machine was stolen. The mucua moved to a better computer. In all these cases you can install a new mucua — but, to the other mucuas on the network, it would be a stranger: another secret name (UUID), another entry in the list, and the old one would stay there, never answering again.

Recreating is installing the new mucua with the same UUID as the old one. Then the other mucuas recognise it: "it's the same one, it's back".

What comes back is the identity, not the content. The knowledge comes back the usual way: synchronising the galaxy with the other mucuas that keep copies (see Fruits of Baobáxia, chapter 08).

Where to find the UUID

• on the site of any mucua on the network: Mucuas → the old mucua → the UUID shows on the page, with a copy button;
• if the old disk still opens: in the mucua.yaml file, in the /var/lib/baobaxia/.baobaxia/ folder.

It looks like this: b0d80df3-a5ce-4177-8e87-22a856bf70df — 32 letters and numbers, in groups of 8-4-4-4-12.

From the boot menu

Only on the first boot (after that the option goes away). In the menu, choose Baobaxia: primeiro boot RECRIANDO uma mucua que ja existe (UUID e nome) (first boot RECREATING a mucua that already exists — UUID and name):

The screen asks for the UUID and the name (Nome da mucua). The name is optional (just Enter uses "Minha Mucua") and goes without accents — you can correct it later on the site:

The keyboard is the US layout (chapter 02). The UUID is long: check it calmly before pressing Enter.

From the file

Before switching on, in baobaxia-rede.txt (chapter 01):

MUCUA_UUID=b0d80df3-a5ce-4177-8e87-22a856bf70df
MUCUA_NOME=Abdias

Carefully

• A UUID in the wrong format makes the first boot stop, with a warning on screen, until it is corrected in the file. That's on purpose: better to stop than to become, without anyone noticing, a new mucua.
• What was typed in the menu is saved in the file: if the first boot fails and tries again, it is still the same mucua.
• When it works, the two lines are emptied and the option leaves the menu — so the stick doesn't carry that UUID to another machine.
• Never recreate a mucua that is still working somewhere else: the two would have the same name, and the network wouldn't know which is which.