Re: How to do this ?

[Erwan David <erwan@rail.eu.org>]

Le 11/10/2014 18:45, Steve Litt a écrit :
> On Sat, 11 Oct 2014 13:38:05 +0300
> Andrei POPESCU <andreimpopescu@gmail.com> wrote:
>
>> On Vi, 10 oct 14, 19:51:50, Erwan David wrote:
>>> I want to have a system which boots, and starts a subset of daemons.
>>>
>>> Then afterward I ssh to it, do something which 1) mount an encrypted
>>> disk, 2) start other daemons (which depends on the encrypted disk).
>>>
>>> I know how to do this with policy-rc.d, how can I do this with
>>> systemd ?
>> My first though on doing this with sysv-rc would have been runlevels, 
>> why do you even need policy-rc.d?
> LOL, when I read the original question, I didn't answer because I
> thought he was inisting on a policy-rc solution.
>
> If policy-rc.d weren't required, and if it were me, the solution would
> be totally obvious, because I'm a daemontools type of guy...
>
> I'd put all the services to be started secondarily under daemontools.
> I'd have a directory somewhere, with empty filenames corresponding to
> the services I want to bring up secondarily: /home/slitt/servicelist or
> whatever.
>
> Then I'd make these shellscripts:
>
> #########################################
> #!/bin/sh
> # this is uppp.sh
>
> if bring_up_encrypted_filesystem.sh; then
>   for f in /home/slitt/servicelist; do
>     rm -f /service/$f/down
>     svc -u /service/$f
>   done
> else
>   handle_encrypt_up_error.sh
> fi
> #########################################
>
> #########################################
> #!/bin/sh
> # this is downnn.sh
>
> for f in /home/slitt/servicelist; do
>   touch /service/$f/down
>   svc -d /service/$f
> done
> if bring_down_encrypted_filesystem.sh; then
>   poweroff
> else
>   handle_encrypt_down_error.sh
> fi
> #########################################
>
> Obviously I haven't tech-edited these, and also obvious I left a lot of
> stuff for the encrypted disk as an exercise for the reader, but
> basically:
>
> To boot up, you boot up, ssh in, and run uppp.sh
>
> To shut down, you ssh in, run downnn.sh.
>
> If you sometimes need to reboot instead of powering off, you could
> remove the shutdown from downnn.sh and just do it manually while you're
> ssh'ed in.
>
> HTH,
>
> SteveT
>
> Steve Litt                *  http://www.troubleshooters.com/
> Troubleshooting Training  *  Human Performance
>
>
The problem is not today setting, which may not be perfect, but is
functionnal, but the solution for when systemd is not avoidable.

However I retain the daemontools solution.