[sheepdog] [PATCH] add INFO level operation logging on each node.

[Hitoshi Mitake]

At Tue, 21 Jan 2014 20:38:07 +0900,
Matsuo Yoshinori wrote:
> 
> [1  <multipart/alternative (7bit)>]
> [1.1  <text/plain; ISO-8859-1 (7bit)>]
> I think the both logging function are needed because of the reasons below.
> 
> Reason:
> 1. The dog and the sheep are another process.
> Even if dog is working good but sheep process may have some trouble.
> Then we need to track on the sheep process, too.
> 
> 2. The reason that we want a logging function on sheep process.
> The sheep processes are always in the cluster, but dog are not.
> We may not be able to get the evidence log,
> if dog command was issued from unknown or operators temporary host.
> 
> 3. The reason that we want a logging function on dog command.
> Sheep can't log dog command level directry but dog can log more readable
> log with all command options.
> The operator wants to see dog command level evidence first, when checking
> what is done to cluster.
> 
> I would like to know Hitoshi's opinion, too.

I agree with Matsuo-san's opinion. dog and sheep can be executed on
different hosts, so log for evdence should be written by both of
them.

In addition, we are building a product, not a service. We need to
analyze problems based on logs produced by users' deployments when
they are in trouble. For doing smooth trouble shooting, we need logs
as much as possible. Because we wouldn't be able to access to users'
deployments directly.

For expanding use case of sheepdog, this logging enhancement would be
helpful.

Thanks,
Hitoshi