On Saturday, June 28, 2014 01:39:41 PM Neil Bothwick wrote: > On Sat, 28 Jun 2014 11:36:11 +0200, J. Roeleveld wrote: > > I need a way to add dependencies to services which are provided by > > different servers. For instance, my mail server uses DNS to locate my > > LDAP server which contains the mail aliases. All these are running on > > different machines. Currently, I manually ensure these are all started > > in the correct sequence, I would like to automate this to the point > > where I can start all 3 servers at the same time and have the different > > services wait for the dependency services to be available even though > > they are on different systems. > > > > All the dependency systems in the init-systems I could find are all > > based on dependencies on the same server. Does anyone know of something > > that can already provide this type of dependencies? Or do I need to > > write something myself? > > With systemd you can add ExecStartPre=/some/script to the service's unit > file where /some/script waits for the remote services to become available, > and possibly return an error if the service does not become available > within a set time.
That method works for any init-system and writing a script to check and if necessary fail is my temporary fall-back plan. I was actually hoping for a method that can be used to monitor availability and, if necessary, stop services when the dependencies disappear. -- Joost
