Postfix: queue management commands

Here are some postfix queue management commands that I find myself using regularly (on an Ubuntu server):

Slow login into Ubuntu via SSH

Fresh install of Ubuntu Server 12.04 LTS: After installed SSHD, I found that logging in remotely was a time-consuming process as the password prompt took ages to pop up after the username prompt. Binging about, I found that this was due to SSHD performing a reverse DNS lookup of my IP to potentially check if all is kosher. Turning this check off fixes the issue:

Screen .screenrc configuration

All those who SSH into servers ought to use GNU Screen. The following is some additional configuration that can be added to a .screenrc file in your home directory. These lines do wonders to the usability of the system:

The drush command '@hostmaster pm-enable hosting_queued' could not be found

Installing Aegir 2 on a fresh install of Ubuntu Saucy in a Virtualbox, I ran into the following message:

The drush command '@hostmaster pm-enable hosting_queued' could not be found.

To fix this run, sudo mysql_secure_installation and ensure that you remove anonymous users. This should do the trick.

this kernel requires an x86-64 CPU, but only detects an i686 CPU, unable to boot

Using Virtualbox (4.3.6) on an XP64 machine, I ran into the following error while trying to install a 64-bit version of Ubuntu:

this kernel requires an x86-64 CPU, but only detects an i686 CPU, unable to boot

This happens even if the host machine is a 64-bit machine. To fix this, reboot the box and enter the BIOS. Look around for a virtualisation setting and enable it. Save and exit the BIOS configuration screen.

What to do when 'dpkg --configure -a' does not work?

I recently had trouble with a MySQL installation in Ubuntu. For some reason or the other, during an upgrade to a newer version of mysql-server, the upgrade script had issues stopping the server and the script failed. This meant that apt could no longer function as it kept raising a red flag over the broken upgrade with the following instructions:

Updating Windows Installer on XP 64-bit

I ran into a hitch while trying to install the latest version of TortoiseSVN on my XP 64-bit Windows installation. Apparently, the entire world has forgotten about the existence of this variety of Windows. There's absolutely no mention of it anywhere on TortoiseSVN's installer page. The MSI installer failed stating that the version of Windows Installer that I was using was dated and that I needed to update my version of XP (x86) to SP3 or some other drivel like that. TortoiseSVN has no manual install option either. I did the whole Windows Update thing as well, to no avail.

Starting krfb in minimised mode

I've got Kubuntu running my HTPC and XBMC starting up in full screen on boot. Besides XBMC's remotes which I operate from an Android tablet, I also use a VNC client on said tablet to connect to the HTPC to operate other programs. As a VNC server, I've got krfb also starting up on boot which is where my problem lies. krfb does not start minimised in the system tray. There is also no option to get it to do so in its configuration screen.

Here is a guide on how I have krfb configured to start it minimised.

CAPS LOCK issues when VNCing into Kubuntu and krfb

I'm trying to VNC into my Kubuntu box using Jump Desktop from my Android tablet. All works well and everything is quite peachy. Everything that is, except for typing with the keyboard. Typing anything results in letters being displayed in capitals. Using the SHIFT key in the Android keyboard does fuck all. However, when I connected a keyboard to the Kubuntu box and pressed the CAPS LOCK key, my Android keyboard started typing in smalls.

Tranferring a file using PuTTY's pscp

Instead of having to look up the exact syntax for pscp every time, here's a list of examples for future reference. In these examples, I'm transferring a file ( from a Windows host to a Linux server (with the destination path of /home/druss/Desktop/).


Subscribe to RSS