I looked at REG_RESOURCEs a9s well as a few others) but I’m afraid I am going 
to need more specifics.

For example, what query would you recommend to look at say deployment policies 
and cartridge definitions?

From: Imesh Gunaratne [mailto:im...@apache.org]
Sent: 09 May 2015 09:08
To: dev
Subject: Re: Clustered deployments of Stratos

Yes you could refer the tables that have the prefix "REG_".

On Sat, May 9, 2015 at 4:11 AM, Shaheedur Haque (shahhaqu) 
<shahh...@cisco.com<mailto:shahh...@cisco.com>> wrote:
Can you suggest what tables to look at?

From: Imesh Gunaratne [mailto:im...@apache.org<mailto:im...@apache.org>]
Sent: 07 May 2015 18:00

To: dev
Subject: Re: Clustered deployments of Stratos

Hi Shaheed,

Thanks for the clarification! May be the problem is with the MySQL 
active-passive configuration.

I understand that you are switching the same OpenStack volume from active node 
to the passive node (when the passive node becomes active) therefore 
technically it should work. May be we need to investigate this problem further 
by analysing whether data is persisted properly in the active node before the 
passive node becomes active.

Thanks

On Tue, May 5, 2015 at 4:22 PM, Shaheedur Haque (shahhaqu) 
<shahh...@cisco.com<mailto:shahh...@cisco.com>> wrote:
The data is not synchronised between the active and passive nodes. For clarity, 
this is the HA model we had, much as described in the blog:


•        2 nodes, with Pacemaker in active-passive mode.

•        Under Pacemaker control:

o   We run MySQL in active-passive mode, using a single OpenStack volume which 
we attach/reattach as the active role moves around nodes.

o   As the Pacemaker moves the volume, and thus MySQL around on node failures, 
ActiveMQ and Stratos are moved around too.

o   Thus, everything operates in active-passive mode.

Even in this model, as the active Stratos 4.0 is moved around (i.e. the Stratos 
JVM on the old active node has gone with the node, and Pacemaker starts up a 
new Stratos JVM on what used to be the passive node), we found that the 
Cartridge Definition objects were found to be missing and, as a clumsy 
workaround [1], we had to replay the stored copied of them into Stratos using 
the REST API.

With Stratos 4.1, using the new object names , early indications are Deployment 
Policies and Application Deployment policies are lost as the active fails over 
to the passive. If anything, these objects are more likely to hit the problems 
of [1], since Stratos 4.1 expects these to be tweaked on the fly (min/max etc).

Thanks, Shaheed

[1] Clearly, this loses any changes that were not in the stored copies.

From: Imesh Gunaratne [mailto:im...@apache.org<mailto:im...@apache.org>]
Sent: 03 May 2015 06:43
To: dev@stratos.apache.org<mailto:dev@stratos.apache.org>

Subject: Re: Clustered deployments of Stratos

Hi Shaheed,

Thanks for taking time to test this!

Just to clarify the exact problem, do you mean that data is not synchronized 
between the active and passive nodes or they are not persisted in the active 
node?

Thanks

On Sunday, May 3, 2015, Shaheedur Haque (shahhaqu) 
<shahh...@cisco.com<mailto:shahh...@cisco.com>> wrote:

I have been looking into our use of Linux HA to setup an Active-Passive 
configuration. Testing indicates that in 4.1 (beta1), several objects seem not 
to be persisted properly. This includes at least:

- Cartridges
- Deployment policies

Am I missing something? Is it safe to workaround this by replaying those 
objects?
________________________________
From: Imesh Gunaratne [im...@apache.org<mailto:im...@apache.org>]
Sent: 23 April 2015 10:47
To: dev
Subject: Re: Clustered deployments of Stratos
Hi Shaheed,

Currently N-way clustering is still not possible with CC, AS & SM. We completed 
the initial phase of this feature however it was not completed. You could refer 
mail thread "[Discuss] Clustering Feature Implementation for 4.1.0-Alpha 
Release" for details.

However at present [1] is valid. We could use Linux HA and deploy CC, AS and SM 
in Active-Passive mode.

Thanks



On Thu, Apr 23, 2015 at 2:41 PM, Shaheedur Haque (shahhaqu) 
<shahh...@cisco.com<mailto:shahh...@cisco.com>> wrote:
Hi,

We currently try to achieve HA with Stratos using something so unpleasant that 
I won’t even describe it here ☺. It has been suggested that Stratos has, for a 
while now, supported a clustered mode of deployment where, given N servers:


•        The SM, AS and MB operate in a N-way clustered mode

•        The CEP operates in a N-way loadsharing mode

•        The Cartridge Agents can react to a failure in one of the N CEPs by 
failing over to one of the other N-1 remaining servers

In looking for documentation on how to set this up, I came across these two 
write-ups [1] and [2]. Questions:


•        Both these documents mention only using N=2. Is that still correct?

•        [1] Seems recently written, and [2] is a little older but not much. 
Are both documents still regarded as current?

Also, I’d love to hear any other experiences people have of running 
configurations like this.

Thanks, Shaheed

[1] 
https://cwiki.apache.org/confluence/display/STRATOS/4.1.0+Configuring+HA+Using+Pacemaker+and+Heartbeat
[2] http://blog.lasindu.com/2014/08/wso2-private-paas-supporting.html






--
Imesh Gunaratne

Technical Lead, WSO2
Committer & PMC Member, Apache Stratos


--
Imesh Gunaratne

Senior Technical Lead, WSO2
Committer & PMC Member, Apache Stratos




--
Imesh Gunaratne

Senior Technical Lead, WSO2
Committer & PMC Member, Apache Stratos



--
Imesh Gunaratne

Senior Technical Lead, WSO2
Committer & PMC Member, Apache Stratos

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