Archive for the ‘Linux’ Category

Highlight text using Grep without filtering text out

Here’s a neat little trick I learned today I thought was worth sharing. Sometimes I want to highlight text in a terminal screen using grep but without filtering other lines out. Here’s how you do it… mysqlbinlog mysql-bin.000473 | grep –color -E ‘^|not closed’; The important part is the regexp in grep. The first section […]

6 Useful Bash tips I wish I knew from day zero

Here’s a few bash commands tricks I wished I’d been shown when I first picked up the shell. Please share any additional favorites you have. Repeat the last command with sudo How often do you type… yum install long-list packages-devel Only to be told… You need to be root to perform this command. Execute the following […]

Kibana splits on hostname

If you’re playing with Kibana and you notice any Pie charts splitting values incorrectly, i.e. on a hostname with hyphen characters, then here’s the fix you need to apply. It’s actually something elasticsearch does… curl -XPUT http://localhost:9200/_template/syslog -d ‘ { “template”: “*syslog*”, “settings” : { “number_of_shards” : 1 }, “mappings” : { “file” : { “properties” […]

Bash script to execute a MariaDB query multiple times

This simple bash script will execute a query 100 times against a MySQL instance. It also uses the time command to report how long the entire process took. I use this for some very simple bench-marking. The query used here creates a temporary table and inserts 100K rows into it. You need the sequence engine […]

Copy date stamped backups with a regex & scp

Lets assume you have a directory of date stamped backups you want to scp to another location… backup_20141003.tar.gz backup_20141004.tar.gz backup_20141005.tar.gz backup_20141006.tar.gz backup_20141007.tar.gz backup_20141008.tar.gz backup_20141009.tar.gz scp can accept a regex like below to do this as a one-liner. Note the quotes are required for the expression to work. scp “user@hostname:/data/backup/backup_2014100[3-9].tar.gz” /path/to/location/ You should see something like […]