Re: Guix "ops"

[Ludovic Courtès]

David Thompson <address@hidden> skribis:

> Ludovic Courtès <address@hidden> writes:
>
>> Perhaps one addition eventually would be to allow IPs to be
>> automatically allocated and have host name lookup DTRT in each VM.
>
> Do you have any idea how we could do that for local VMs?  There's no
> daemon managing the provision of these resources, so I don't know what
> strategy can be used to automatically allocate static IPs.

QEMU allows you to specify the guest’s IP, I think, and apparently it
can create VLANs and connect several unprivileged QEMU instances
together via -net socket (info "(qemu-doc) sec_invocation").

Things like libvirt probably provide a higher-level interface to that.
(I don’t know if it justifies the extra dependency.)

> The automagic hostname lookup part is particularly interesting to me.  A
> more complete deployment configuration would have the web server
> dependent on the db server.  I originally intended to handle this by
> delaying the creation of the web server until after the db server was
> made, and invoking a procedure that accepted the db server's state as
> input and output the correct configuration for the web server.

I’ve seen that Docker can do that.  ;-)  IIRC it populates /etc/hosts in
each container.  That’s something we could do.  Another possibility
would be to rely on mDNS.

> Thinking out loud here: Maybe 'guix deploy' can kick off the
> provisioning for all machines first, and afterwards the OS configs can
> be altered to include the correct /etc/hosts file.

The transform procedure could force the right /etc/hosts in each OS, I
suppose?

Thanks,
Ludo’.