(Migrated) 2 identical cluster setup

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Hi,

I have setup 2 identical clusters under an external load-balancer for active-active HA. These 2 cluster is setup under one OBD and each cluster connected to it’s own redis.

We deploy the same service module in cluster 1 and 2. Then we create in each cluster a http channel to expose the service. However we noticed that whenever we view the service overview, the service in cluster 1 will indicate “PLAIN HTTP: servicename,servicename” and in cluster 2, it will show “PLAIN HTTP: (NONE)”. Is this a bug? Shouldn’t the service overview in cluster2 be showing “PLAIN HTTP: servicename”? See attached images.

Also, I cannot create a new HTTP_Basic_Auth definition using the same name even though i create it in different cluster. It keeps complaining definition exist.

Appreciate if anyone can help.

Thanks.

Keith

From: “Ivan Villareal” ivaano@gmail.com
To: “Keith Phua” keith@science.nus.edu.sg
Cc: “zato-discuss” zato-discuss@lists.zato.io
Sent: Wednesday, May 25, 2016 1:44:13 AM
Subject: Re: [Zato-discuss] 2 identical cluster setup

I have setup 2 identical clusters under an external load-balancer for
active-active HA. These 2 cluster is setup under one OBD and each cluste=
r

connected to it’s own redis.

We deploy the same service module in cluster 1 and 2. Then we create in =
each

cluster a http channel to expose the service. However we noticed that wh=
enever

we view the service overview, the service in cluster 1 will indicate "PL=
AIN

HTTP: servicename,servicename" and in cluster 2, it will show "PLAIN HTT=
P:

(NONE)". Is this a bug? Shouldn’t the service overview in cluster2 be sh=
owing

“PLAIN HTTP: servicename”? See attached images.
I think you are seeing this because the singleton role, from the document=
ation:
For each cluster, exactly one server will be designated to a role of the
singleton server

When the first server in a cluster starts up, it is assigned the role of =
the
singleton server, and the server will periodically update its keep-alive =
flag
in the ODB .

So what happens is that cluster number 2 doesn=E2=80=99t have a singleton=
server because
it is using the same DB as cluster 1.

It doesn’t make sense when the document says that " Multiple clusters can u=
se a single ODB without any interference,…". So I would assume that the OD=
B should cater for the singleton server updates for different cluster.=20

Why don=E2=80=99t you just add all the servers to the same cluster?, and =
just point your
external LB to zato servers directly, you will have the same HA, and your
deployment will be a lot simple.

That’s a good suggestion. However it also mean that I will have to setup a =
3 node redis HA with sentinel. https://zato.io/docs/admin/guide/redis-ha/se=
ntinels.html.=20

Also, I cannot create a new HTTP_Basic_Auth definition using the same na=
me even

though i create it in different cluster. It keeps complaining definition=
exist.
I=E2=80=99ve opened a ticket about this https://github.com/zatosource/zat=
o/issues/663

Great. But mine issue again is not able to create the same username in diff=
erent cluster.=20

On May 24, 2016, at 4:32 AM, Keith Phua < keith@science.nus.edu.sg > wro=
te:

Hi,

I have setup 2 identical clusters under an external load-balancer for
active-active HA. These 2 cluster is setup under one OBD and each cluste=
r

connected to it’s own redis.

We deploy the same service module in cluster 1 and 2. Then we create in =
each

cluster a http channel to expose the service. However we noticed that wh=
enever

we view the service overview, the service in cluster 1 will indicate "PL=
AIN

HTTP: servicename,servicename" and in cluster 2, it will show "PLAIN HTT=
P:

(NONE)". Is this a bug? Shouldn’t the service overview in cluster2 be sh=
owing

“PLAIN HTTP: servicename”? See attached images.

Also, I cannot create a new HTTP_Basic_Auth definition using the same na=
me even

though i create it in different cluster. It keeps complaining definition=
exist.

Appreciate if anyone can help.

Thanks.

Keith <serviceoverviewinC2.jpg> <serviceoverviewinC1.jpg>