How To Fix DNS Lookup Issues on Macos Mojave 10.14.6

Author: , July 22nd, 2020

dscacheutil -flushcache System Preferences -> Network -> Advanced -> DNS -> Add 1.1.1.1, 8.8.4.4 and 8.8.8.8 at the top. If they are already there, CHANGE THE ORDER!

How To Unblock AWS RDS Connections

Author: , October 24th, 2012

Recently, I had a client site outage. AWS had a major EBS failure on Zone B, and one of the instances never recovered. One of the major issues was the inability to connect to the RDS service:

It turns out two steps were required for resolution: 1. Reboot the instance to get network access […]

How To Flush The Mail Queue In Postfix

Author: , December 13th, 2010

Flush the mail queue: # postfix flush OR # postfix -f View the mail queue: # mailq Delete all mail from the queue: # postsuper -d ALL Delete all mails in the deferred queue: # postsuper -d ALL deferred