I had these errors randomly popup too I'm not sure if you have the same issue but your description sounds similar.

My issue was related to my MySQL server having multiple network interfaces with one configured public and one private and these connection errors were a result of how I set up the mysql user. I had it set up as kamailio@'private.ip' but kamailio was actually attempting connection to the public IP (which was not authorized). If you have multiple network interfaces I would suggest checking kamailio.cfg and the user set up to access mysql and verify your IP's/hostnames and maybe even verify on both boxes what interfaces the connections our going out/coming in on.

Benjamin Fitzgerald

LETS Corporation

(925) 235-1154

ben@letscorp.us

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On Fri, Oct 16, 2015 at 7:11 AM, John Billings <jandrewb@gmail.com> wrote:

Both boxes are running Debian 8.

I’m still looking at the mysql logs, but I haven’t found anything relevant, yet.

On Oct 14, 2015, at 5:00 AM, sr-users-request@lists.sip-router.org wrote:

Hello,

do you have centos+selinux? Because I heard about a lot of limits with
the combination of the two.

Have you checked the mysqld syslog messages, anything relevant there?

Cheers,
Daniel

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