How To List Running AWS Instances in all Regions Sorted by LaunchTime and Email in a Monospaced Font

Author: , July 1st, 2019

How To Obtain a Public Key from an AWS .pem Private Key on Linux and Mac

Author: , February 4th, 2019

Use the ssh-keygen command on a computer to which you’ve downloaded your private key .pem file; for example: First, ensure permissions will allow ssh-keygen to work: chmod 600 /path/to/the/file/your-key-pair.pem Then generate an RSA public key: ssh-keygen -y -f /path/to/the/file/your-key-pair.pem > your-key-pair.pub

How To Locate Attached Disk Devices in Linux

Author: , April 24th, 2018

https://linux.die.net/man/8/lsblk # lsblk -a

How To Upgrade MySQL from 5.5 to 5.7 on CentOS/AWS Linux

Author: , December 7th, 2017

START: Server version: 5.5.54-log MySQL Community Server (GPL) FINISH: Server version: 5.7.20-log MySQL Community Server (GPL)

How To Block an Entire TLD in Postfix

Author: , September 13th, 2016

Step 1. Execute the following two commands: postconf -e smtpd_sender_restrictions=pcre:/etc/postfix/rejected_domains postconf -e reject_unauth_destinations=pcre:/etc/postfix/rejected_domains If that doesn’t work, you may hand-edit main.cf and add/edit these lines:

Step 2. Create the regex filter file: vim /etc/postfix/rejected_domains

Step 3. Signal Postfix to reread the config: postfix reload NOTE: Do NOT use the postmap command for the […]

How To Install and Use the screen Command on AWS Linux

Author: , August 12th, 2016

Install it: yum install screen Start it up: screen Detach from the session: Control-a d Re-attach to the session later on: screen -r This is a good reference guide: https://www.rackaid.com/blog/linux-screen-tutorial-and-how-to/

How To Enable DNS Hostnames for AWS VPC

Author: , August 8th, 2016

When you launch an instance into a VPC, AWS provides the instance with a public DNS hostname only if DNS hostnames are enabled for the VPC. By default, DNS hostnames are enabled only for default VPCs and VPCs that you create using the VPC wizard in the VPC console. If you enable DNS hostnames and […]

How To Fix Apache VirtualHost Overlap on Port 443 on AWS Linux

Author: , July 4th, 2016

If you get this error when starting Apache or via apachectl configtest: [warn] _default_ VirtualHost overlap on port 443, the first has precedence then you must add: NameVirtualHost *:443 to /etc/httpd/conf/httpd.conf, then restart Apache

How To Fix a “Corrupted index cache file” Error in Dovecot

Author: , June 17th, 2016

Jun 17 00:02:45 inbound dovecot: IMAP(yourName): Corrupted index cache file /home/yourName/Maildir/dovecot.index.cache: invalid record size

As always, YMMV. Proceed with caution.

How To Install the AWS CLI

Author: , March 29th, 2016

http://docs.aws.amazon.com/cli/latest/userguide/cli-chap-getting-set-up.html http://docs.aws.amazon.com/cli/latest/userguide/cli-chap-getting-started.html

ls -l ~/.aws

cat ~/.aws/config

cat ~/.aws/credentials