Eric Shalov – Systems Consultant

If you’re seeing this in the /var/log/syslog on your BIND DNS server:
..it means that a client has asked your server to look up a domain name that your server didn’t know about, and when it forwarded the request to it’s forwarders, the remote DNS server refused to respond. A packet trace on your DNS server shows exactly...

If you see this when you run “apt-get update” on Ubuntu, “apt” is unable to find the Ubuntu package repository’s key in it’s GPG keyring:
You can see the keyrings with “apt-key list”:
Solution:

If you rely on PuppetDB, and PuppetDB is not running, you may see this when the agent attempts to run:
$
root@client:~# puppet agent -t

If your hard disk fills up on your Ubuntu system, you may get the following console message, and be unable to login via SSH:
What does it mean?
Plymouth is the application which provides the graphical “splash” screen when booting and shutting down an Ubuntu system. If the root drive fills up, Plymouth won’t function correctly, so it might be the first indication of the lack of free space....