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Postfix "unavailable. unsupported dictionary type 1111" on restart? Check your brackets!

I was recently modifying a Postfix config to do some debug logging of transactions for a specific IP addresses. To do this, I modified the smtp and smtps services in master.cf to get the most verbose logging possible.  However, I'd failed to remember to encapsulate the IPv6 address with brackets. And so, I got this in the log after restarting […]

Canon Pixma owners: this one simple trick makes your printer's feed rollers able to grab paper again!

I have a cheap Canon Pixma MG5750, a Currys PC World purchase when I needed a cheap multifunction printer fast. Was handy at £45 (another set of genuine ink for it costs the same, go figure) but obviously I never expected it to be perfect. Unfortunately, one of the fundamental requirements of any printer - to be able to take […]

Tiplet: no SNMP replies? Fix broken SNMP responses in Windows Server 2008, Windows 8

I encountered a weird problem on a Windows Server 2008 R2 install which had dual NICs on the same physical network (different subnets, DNS and gateways) - you could interrogate its SNMP agent and you wouldn't get a response even though the right community was set and you might initially see it working properly! This borkage would happen indefinitely after […]

Tiplet: monitor realtime web site traffic on a Linux server with tmux and tail

I run a VPS which has numerous sites on it. Whilst I was trying to pin down the root cause of sporadic hard lockups and runaway memory usage, I settled on a somewhat inefficient (yet very handy) line of code which I run inside a tmux session over a PuTTY SSH connection (two other panes run iftop and watch --interval=0.1 […]

Tiplet: one-click Lock Screen for OS X

It must be in the name... Chris Cook devised an excellent little (Automator-based) scriptlet, self-contained as an .app Obviously (obviously, natch) if you hit Command-Option-Q for Quick User Switch - which is one HELL of a difficult keyboard combo if you can't get your thumb to do the double keypress - plus it will close all open apps and processes […]

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