Entries from May 2019

How To Remove A File From The git Staging Pre-Commit List

Author: , May 31st, 2019

Quickref: How to Remove a file from the staging area

The Story Recently, I accidentally added some files to git’s pre-commit phase, i.e.:

For example, here is how to handle the above situation:

To better understand, here are the phases/states/stages that git uses: Untracked – when a file is first created, git […]

How To Use Regex Negative Lookahead To Exclude Strings

Author: , May 31st, 2019

I have a task in Perl to list specific files based on pattern match, those with and those without the string “_from_”. There are two files in the directory to filter: static-east.properties static-east_from_west.properties To capture the files with the _from_ string was easy:

To capture the files WITHOUT the _from_ string was not quite […]

How To Force csshX To Tile In Columns

Author: , May 28th, 2019

I use csshX on a daily basis. The default layout on my screen for three nodes is one column with three rows, one per node. This layout is excellent for visual positioning, but does make it harder to read long output. For this purpose, I start csshX using the column quantity specifier -x and I […]

The Important Role of a Tungsten Rollback Error

Author: , May 24th, 2019

The Question Recently, a customer asked us: What is the meaning of this error message found in trepsvc.log? 2019/05/14 01:48:04.973 | mysql02.prod.example.com | [east – binlog-to-q-0] INFO pipeline.SingleThreadStageTask Performing rollback of possible partial transaction: seqno=(unavailable) Simple Overview The Skinny This message is an indication that we are dropping any uncommitted or incomplete data read from […]

Understanding Cross-Site Replication in a Tungsten Composite Multi-Master Cluster for MySQL, MariaDB and Percona Server

Author: , May 22nd, 2019

Overview The Skinny In this blog post we will discuss how the managed cross-site replication streams work in a Composite Multi-Master Tungsten Cluster for MySQL, MariaDB and Percona Server. Agenda What’s Here? Briefly explore how managed cross-site replication works in a Tungsten Composite Multi-Master Cluster Describe the reasons why the default design was chosen Explain […]

Performance Tuning Tungsten Replication to MySQL

Author: , May 21st, 2019

The Question Recently, a customer asked us: Why would Tungsten Replicator be slow to apply to MySQL? The Answer Performance Tuning 101 When you run trepctl status and see: appliedLatency : 7332.394 like this on a slave, it is almost always due to the inability for the target database to keep up with the applier. […]

How To Fix rsync Packet Corrupt Errors

Author: , May 10th, 2019

I was getting rsync errors from one source host:

Finally tracked it down to the application “Little Snitch”. Needed to fully uninstall it and reboot to get the problem solved.

SSH Differences Between Staging and INI Configuration Methods

Author: , May 7th, 2019

The Question Recently, a customer asked us: If we move to using the INI configuration method instead of staging, would password-less SSH still be required? The Answer The answer is both “Yes” and “No” No, for installation and updates/upgrades specifically. Since INI-based configurations force the tpm command to act upon the local host only for […]