[mysql] Fix slave_running for mysql 5.7 with slave binlog #2610
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When a MySQL 5.7 is a slave _and_ has a running binlog with no downstream slaves attached, this check assumed that the instance was a master with no running slaves. Fix it so that it checks for Slave_IO_Running and Slave_SQL_Running before checking for Binlog_enabled and Slaves_connected. [mysql] some more PR fixes.
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@nrw505 this would be the rebased PR. I believe it respect your changes to the logic and authorship. Thanks for your contribution. |
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| # if we don't yet have a status - inspect | ||
| if slave_running_status == AgentCheck.UNKNOWN: | ||
| if self._is_master(slaves, binlog_running): # master |
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On MySQL < 5.7, couldn't the same issue arise here? (i.e. if we have a slave with binlog running, we'd regard it as a master because of this condition and send a WARNING status)
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Well yes - that occurred to me as well - but I don't think there's a clear-cut way of deciding if a certain instance is a master or a slave on earlier versions. One option could be setting it in the config file.
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An optional setting in the conf file sounds good to me! (for instance an option to force the check to regard the server as a master even when binlog is running)
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@truthbk Added in one comment, let me know what you think :) |
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LGTM! (my comment about mysql < 5.7 can be addressed later in a separate PR, feel free to merge this PR) |
When a MySQL 5.7 is a slave and has a running binlog with no
downstream slaves attached, this check assumed that the instance was a
master with no running slaves.
Fix it so that it checks for Slave_IO_Running and Slave_SQL_Running
before checking for Binlog_enabled and Slaves_connected.
This PR should supersede #2493 - it is essentially no more than a rebase of it. We first look at the slave variables available in most 5.7+ versions, and if we don't yet have concluded on a status, we then look at possible master, slave combinations.