proxysql: fix keepalived healthcheck to use MySQL protocol

The check_alive_proxysql.sh script piped raw ASCII text
("show info\n") directly into the admin socket via socat, bypassing
the MySQL handshake.

ProxySQL's MySQL_Data_Stream interprets the first 3 bytes of "show"
as a little-endian packet length (7301235), which has always been
semantically wrong - the check only appeared to work because socat
received ProxySQL's binary handshake greeting back and exited 0.

ProxySQL 3.0.9 introduced a pre-authentication bounds check
(GHSA-58ww-865x-grpr) that explicitly rejects first packets whose
declared length exceeds the 32 KB input queue capacity and closes
the connection.
This causes socat to exit non-zero, making keepalived mark ProxySQL
as unhealthy on every check interval.

Replace the raw socat probe with a mariadb client connection that
speaks proper MySQL protocol against the admin socket.

Closes-Bug: #2155865

Depends-On: https://review.opendev.org/c/openstack/kolla/+/992394

Change-Id: Ic090916509cbb1bd98c96e8beb32ec9e90bfc6aa
Signed-off-by: Michal Nasiadka <mnasiadka@gmail.com>
(cherry picked from commit 1e0fa6c62bbb6129f29f01605a00ce3e0f50e27a)

0 files changed, 0 insertions, 0 deletions