What does “error (unexpected RCODE REFUSED)” mean?

If you’re seeing this in the /var/log/syslog on your BIND DNS server: Jul 14 00:56:13 kla-dns-01 named[8255]: error (unexpected RCODE REFUSED) resolving ‘75.1.33.112.in-addr.arpa/PTR/IN’: 211.136.17.105#53 ..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 …

Continue reading ‘What does “error (unexpected RCODE REFUSED)” mean?’ »

What does “NO_PUBKEY 40976EAF437D05B5” mean?

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: Reading package lists… Done W: GPG error: http://us.archive.ubuntu.com precise Release: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY 40976EAF437D05B5 W: GPG error: http://security.ubuntu.com precise-security …

Continue reading ‘What does “NO_PUBKEY 40976EAF437D05B5” mean?’ »

What does “mountall: Disconnected from Plymouth” mean?

If your hard disk fills up on your Ubuntu system, you may get the following console message, and be unable to login via SSH: mountall: Disconnected from Plymouth Ubuntu 12.04.5 LTS dbserver ttyS0 dbserver login: What does it mean? Plymouth is the application which provides the graphical “splash” screen when booting and shutting down an …

Continue reading ‘What does “mountall: Disconnected from Plymouth” mean?’ »

How do I monitor a server behind a firewall with Nagios?

Nagios comes with a client-side agent called NRPE that the Nagios server contacts on port 5666 to run remote service-checks, but what if the server is firewalled?? There is a solution, using a feature of Nagios called “passive checks”.  Its called that because Nagios will passively wait for the client servers to actively check-in with their condition. …

Continue reading ‘How do I monitor a server behind a firewall with Nagios?’ »

How do I pin packages in APT?

You can tell APT to use a particular newer version of a package from the ‘testing’ Debian distribution (“jessie”) using APT package “pinning”. You’ll need to specify any dependent packages as well. For example, to run “graphite” from ‘testing’, create /etc/apt/preferences.d/graphite: Package: graphite-web python-django-tagging graphite-carbon python-whisper libc6 libc6-dev Pin: release n=jessie Pin-Priority: 900 Make sure …

Continue reading ‘How do I pin packages in APT?’ »

How do I make a Debian package?

To make a .deb package for use with Debian / Ubuntu: $ sudo apt-get install devscripts debhelper Rename the source tarball following the syntax package name_1.x.orig.tar.gz: $ mv go1.3.src.tar.gz go_1.3.orig.tar.gz Extract the tarball: $ tar xf go_1.3.orig.tar.gz Go into the source directory and create a “debian” subdirectory under it: $ cd go $ mkdir debian …

Continue reading ‘How do I make a Debian package?’ »