[
https://issues.apache.org/jira/browse/WHIRR-266?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13023497#comment-13023497
]
Hyunsik Choi commented on WHIRR-266:
------------------------------------
How fine should we separate generic functions from install and configuration
scripts? Above all, I would like to discuss this issue.
In general, most services may need the following steps:
* launch instances
* fetch a service program from specific URLs or local tarballs
* install the service program (if necessary, it can be divided to unpack and
copy)
* configure the service by user configuration
* launch services
* stop services
* cleaning the service program (remove the service program and configuration)
* stop instances
If we combine them, implementing new features (e.g., restarting service, adding
additional cluster nodes, and reusing cluster nodes) and developing new
services would be easy.
> Separate tasks of both install and configuration scripts into more generic
> and detailed functions
> -------------------------------------------------------------------------------------------------
>
> Key: WHIRR-266
> URL: https://issues.apache.org/jira/browse/WHIRR-266
> Project: Whirr
> Issue Type: New Feature
> Components: core
> Reporter: Hyunsik Choi
> Fix For: 0.5.0
>
>
> Using whirr, I experimented some problems. Especially, if at least one of the
> steps for installing and configuring a service meets some exception or error,
> whirr cannot construct the running cluster. In another case, some of entire
> clusters do not startup by whirr due to unknown reasons. In both cases, users
> have to recover them manually. It may be really burden for users.
> However, the current implementation does not support any recovery ways. In
> addition, service scripts (install and post-configure) bundles up too many
> tasks. For example, for hadoop service the configuration script mounts
> devices, configures *-site.xml files, and executes the service start script.
> It makes users hard to reuse that scripts.
> Thus, I propose that we separate both scripts (i.e., install and
> post-configure) into more normalized and detailed functions, such as
> *service-clean, service-install, service-configuration, service-start, and
> service-stop*. In addition, they should be executable individually by a user.
> I expect that it will give us many benefits: 1) it makes debugging easier 2)
> when an exception or error occurs during starting a service, a user can
> recover easily the cluster by using appropriate functions.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
