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