edtjones

SET @history_interval = 7;
SET @trends_interval = 90;

DELETE FROM alerts WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);
DELETE FROM acknowledges WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);
DELETE FROM events WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);

DELETE FROM history WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);
DELETE FROM history_uint WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);
DELETE FROM history_str WHERE (UNIX_TIMESTAMP(NOW()) - clock) > (@history_interval * 24 * 60 * 60);

yeokm1

Read-only FS on Arch Linux ARM

Unlike your typical computer where you usually shutdown properly, I cannot rely on this during the use of my Raspberry Pi. If the Raspberry Pi is improperly shutdown too many times, data corruption in the file system leading to unbootable SD card may result. So we should use a read-only file system.

Full instructions and explanations are obtained from this link but you can run these commands directly. I modified some of the instructions for personal convenience.

Login with default username: alarm, password: alarm

#Optionally enable root over SSH. The rest of these instructions assume u are in root.

thebucknerlife

#Simple Authentication with Bcrypt

This tutorial is for adding authentication to a vanilla Ruby on Rails app using Bcrypt and has_secure_password.

The steps below are based on Ryan Bates's approach from Railscast #250 Authentication from Scratch (revised).

You can see the final source code here: repo. I began with a stock rails app using rails new gif_vault

##Steps

KartikTalwar

The fastest remote directory rsync over ssh archival I can muster (40MB/s over 1gb NICs)

This creates an archive that does the following:

rsync (Everyone seems to like -z, but it is much slower for me)

• a: archive mode - rescursive, preserves owner, preserves permissions, preserves modification times, preserves group, copies symlinks as symlinks, preserves device files.
• H: preserves hard-links
• A: preserves ACLs