Here’s What’s Happening in That Viral Oil Well Bitcoin Mining Video
A video of a bitcoin mining rig on an oil well got thousands of retweets and replies, criticizing it for destroying the planet—but it’s not that simple.
— Read on www.vice.com/en/article/dy8b9y/natural-gas-oil-bitcoin-mining-rig-viral-video
Radiative Cooling and Solar Heating From One System – No Electricity Needed
Radiative Cooling and Solar Heating From One System – No Electricity Needed
— Read on scitechdaily.com/radiative-cooling-and-solar-heating-from-one-system-no-electricity-needed/
Cleaning Up WordPress – Large wp_options.idb
Did your tiny AWS Bitnami WordPress server run out of disk space? The culprit may be unoptimized data tables in MySQL. Finding a 4.9GB wp_options.idb file on your server is not as uncommon as you may think. What makes it surprising is when you look at your wp_options entries and discover there are only 300 rows in that table with limited text in the option_value column.
Thankfully there is an easy fix as long as you can get enough disk space to manage the task. Start by looking for any log files or other files you are CERTAIN you don’t need so you can shut down web, php, and mysql services.
Finding Large Files
# sudo find / -xdev -type f -size +50M -print | sudo xargs ls -lh | sudo sort -k5,5 -h -r
This command finds all files on the drive over 50M in size.
Look for specific MySQL raw data files (wp_options.idb for example) in that list. Remember the table name for later.
Stopping System Services
Stop the services. On an AWS Bitnami WP server they have their own special control scripts in place of the standard Linux services library.
bitnami@ip-172-31-87-127:/opt/bitnami/mysql$ sudo /opt/bitnami/ctlscript.sh stop mysql usage: /opt/bitnami/ctlscript.sh help /opt/bitnami/ctlscript.sh (start|stop|restart|status) /opt/bitnami/ctlscript.sh (start|stop|restart|status) mysql /opt/bitnami/ctlscript.sh (start|stop|restart|status) php-fpm /opt/bitnami/ctlscript.sh (start|stop|restart|status) apache help - this screen start - start the service(s) stop - stop the service(s) restart - restart or start the service(s) status - show the status of the service(s)
Stop all the services, then start MySQL only.
Cleaning Up MySQL
If you are doing system admin commands you should know how to find your data access credentials in the wp-config.php file. No need to go into that here. Find the credentials and login to MySQL.
No OPTIMIZE that table (and any others that you suspect have unusually large .idb files).
mysql> OPTIMIZE NO_WRITE_TO_BINLOG TABLE wp_options;
That’s it. One simple command may easily recover 4.9GB of disk space , making a 4.9GB file on a 9GB drive get back to a more reasonable 10MB.
Why WordPress core or cron jobs are not doing this on a regular basis is a question for another day…
AWS LEMP Stacks and EFS Issues
Lesson learned — if you are using EFS on production systems you want to be using provisioned throughput mode.
But, before we get into that, let’s go over the details of this implementation…
Service Configuration
We utilize AWS EC2 instances to run multiple WordPress sites hosted in different directories. The configuration is fairly standard: 2+ servers configured as part of an load-balanced cluster. The servers run from the same image meaning they use the same underlying software stack.
Part of that image includes a mounted EFS (Elastic File Storage) directory , used to share WordPress resources between all nodes in the cluster. The original architecture was designed to host not only the typically-shared wp-content/uploads folder of WordPress via this EFS mount but also the code. The thought was that sharing the code in this way would allow a system admin to easily update WordPress core, plugins, or themes from the typical wp-admin web login. Any code updates would immediately be reflected across all nodes.
EFS Web App Code Hosting – A Bad Idea
Turns out this is a bad idea for a few reasons. First of all, EFS volumes are mounted using the NFS4 (network file storage) protocol — this defines how the operating system handles file read/write operations for a network mounted drive. While NFS4 is fairly robust, the throughput of ANY network drive, even on a high speed AWS data center backbone, is much slower than a local drive such as an EBS volume.
That means that even on a good day every PHP file, JavaScript file, or anything else needed to serve up that WordPress web page are going to be a bit slower than normal.
However, the bigger problem comes to light if you happen to choose the default, and pushed as “the mode to use” by Amazon, EFS throughput mode known as “Burst mode”.
Internet Enabled Voting For US Elections
Internet enabled voting is a must IMO. Many that are afraid of the security risks and remote hacking have a very shallow, if any, understanding of the risks involved.
To claim physical (paper) voting is more secure is absurd. Every country that has used that system, including ours, has encountered fraud in some form.
Maybe this is the perfect catalyst for getting our Internet providers to finally enable IPV6. It would make external attacks a couple orders of magnitude more difficult. Not too mention providing direct 1:1 accountability to track every single device used to vote.
