(8.4) PXC-4558: mysql cannot connect to mysql-server in post-processing, if the host is not localhost in the .mylogin.cnf #1989
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if the host is not localhost in the .mylogin.cnf https://perconadev.atlassian.net/browse/PXC-4558 Problem: If .mylogin.cnf file is present and it contains 'host' specified which is not localhost, the SST script is not able to connect to post-processing (post-sst) mysqld instance and SST fails. Cause: SST script, on both sides, donor and joiner, uses socket protocol to connect to the local mysqld instance (mysql, mysqladmin, pxb). If .mylogin.cnf file is present and contains 'host' parameter, it takes precedence over command line options, even if `--protocol=SOCKET' is specified explicitly. On joiner side, after SST, so-called post-processing mysqld instance is started. It has networking disabled, the only way to connect is via socket. Having .mylogin.cnf file in place causes mysql and mysqladmin to try TCP transport instead of the socket and SST fails. As donor instance has networking enabled, this issue unlikely to be visible on that side. However, if .mylogin.cnf file is present and contains 'host' and not correct 'port', the donor side will fail as well Solution: For SST environment (SST script), override .mylogin.cnf by exporting MYSQL_TEST_LOGIN_FILE env variable.
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(8.4) PXC-4558: mysql cannot connect to mysql-server in post-processing, if the host is not localhost in the .mylogin.cnf Cherry pick commit a6afd29
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https://perconadev.atlassian.net/browse/PXC-4558
Problem:
If .mylogin.cnf file is present and it contains 'host' specified which is
not localhost, the SST script is not able to connect to post-processing
(post-sst) mysqld instance and SST fails.
Cause:
SST script, on both sides, donor and joiner, uses socket protocol to
connect to the local mysqld instance (mysql, mysqladmin, pxb).
If .mylogin.cnf file is present and contains 'host' parameter, it takes
precedence over command line options, even if `--protocol=SOCKET' is
specified explicitly. On joiner side, after SST, so-called
post-processing mysqld instance is started. It has networking disabled,
the only way to connect is via socket. Having .mylogin.cnf file in place
causes mysql and mysqladmin to try TCP transport instead of the socket
and SST fails.
As donor instance has networking enabled, this issue unlikely to be
visible on that side. However, if .mylogin.cnf file is present and
contains 'host' and not correct 'port', the donor side will fail as well
Solution:
For SST environment (SST script), override .mylogin.cnf by exporting
MYSQL_TEST_LOGIN_FILE env variable.