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Managing SSH Known Hosts With SSSD And LDAP

For various reasons, I manage on-premises, non-cloud infrastructure. For centralized authentication, I use PAM and OpenLDAP along with SSSD for purposes of caching for availability and load reduction. I rely on the openssh-lpk.openldap.schema LDAP schema for passwordless authentication with OpenSSH, and, recently, I discovered that the same schema can be ... read more

Fun MySQL fact of the day: buffer pool size

Yesterday, we started to discuss the InnoDB buffer pool and I noted that 80% of a system's memory makes a decent starting size for the buffer pool. However, this is somewhat meaningless since we didn't consider how much memory we'd want our system to have. Today we will. ... read more

Fun MySQL fact of the day: redo logs

Over the last few weeks, we've considered how useful the MySQL binary log can be, but you may be thinking, "if the binary log doesn't get written until commit, how does MySQL undo a transaction if it crashes?". And, well, if you remember back through March and April, you'll ... read more

Fun MySQL fact of the day: group commit

We now know that each MySQL thread has its own binary log cache to which it writes the binary log events for a single transaction. We also briefly discussed that MySQL will, upon commit of a transaction, write the thread's binary log cache to the actual binary log file. And ... read more

Fun MySQL fact of the day: binlog cache overflow

Yesterday, we started to consider how MySQL writes its binary log file, and we started to look at how MySQL uses a per-thread binary log cache, which, by default, is 32KB. Depending on your systems' access patterns, however, 32KB may seem rather small. For example, what if you frequently ... read more

Fun MySQL fact of the day: binlog cache

By now, I think we have a shared understanding that the binary log is an important feature in MySQL. And maybe, you may have been wondering, "how does the binary log get recorded"? And that's a good question with a couple fun facts we'll look at next! ... read more
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