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Hi all,

I'm Nobumasa Yukutomi.  I'm working on Designate since last year.

We are using Designate for '20141003' Git Hub repository of Icehouse.

We have built Designate with mysql(Percona) cluster shown below.


    designate.conf                  designate.conf
      IP:xxx.xx.x.x                   IP:yyy.yy.y.y
          A-side                          B-side
  -----------------               -----------------
  | designate-api |               | designate-api |
  -----------------               -----------------
          |                               |
  -----------------    cluster    -----------------
  |   rabbitMQ    |---------------|   rabbitMQ    |
  -----------------               -----------------
          |                               |
  --------------------            --------------------
  | designate-central |           | designate-central |
  --------------------            --------------------
          |                               |
          |IP:xxx.xx.x.x                  |IP:yyy.yy.y.y
  ------------------   cluster    ------------------
  | mysql(Percona) |--------------| mysql(Percona) |
  ------------------              ------------------
          |                               |
          |                               |
  -----------------               -----------------
  |   PowerDNS    |               |    PowerDNS    |
  -----------------               -----------------

Let's assume some situation that mysql cluster encounters some problem. So
let's stop B-side mysql.

The A-side mysql(active) itself continues running. But designate-api
services of both sides stop working, even if the process of designate-api
continues running on both sides.  User gets returned Error500(internal
server error) from designate-api.

Here are more details.

1. Listing domains
For example, if a user access designate-api of A-side, designate-central
accesses to both sides of mysql and the user experiences to succeed and
fail to list domains every other time.

2. Listing records
Also, listing records fails 100% in both sides when a user accesses to
designate-api of either A-side or B-side.

And here are my questions.

Question 1
In designate.conf of A-side, the destination of mysql is
A-side IP: xxx.xx.xx

In designate.conf of B-side, the destination to mysql is
B-side IP: yyy.yy.yy

But, for some reason, designate-central accesses to both IP addresses.

I would like to know why this is happening.

Question 2
I would like to know how to change configuration to make designate-central
to access "only" to active-mysql, not to inactive-mysql.

Thank you in advance.

Best regards,

---
Nobumasa Yukutomi yukutomi at m.ieice.org