Category Archives: Linux

The IT Detective Agency: the vanishing certificate error

Intro I was confronted with a web site certificate error. A user was reluctant – correctly – to proceed to an internal web site because he saw a message to the effect: I tried it myself with IE and got … Continue reading

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Whois information without the pushy hard sell tactics

Intro Did you ever want to learn about a domain registration but were put off by the hard sell tactics that basically all web-based whois searches subject you to? Me, too. Here’s what you can do. The details Linux – … Continue reading

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Measuring bandwidth on Checkpoint Gaia

Intro Sometimes you don’t have the tools you want but you have enough to make do. Such is the case with the command line utilities of the CLI of Checkpoint Gaia. It’s like a basic Linux. The company I consult … Continue reading

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Multiple IPs on the Raspberry Pi

Intro In my previous post I showed how to turn a Raspberry Pi plus USB camera into something like an IP camera. In the course of that work I found it wasn’t so easy as it was in the past … Continue reading

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Raspberry Pi USB webcam turned into IP camera

Intro Why would you even want to do this when you can buy a native IP webcam for less? I’m not sure, but i found myself in this situation so it could happen to others, and I found some things … Continue reading

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A first taste of OpenCV on a Raspberry Pi 3

Intro I’ve done a few things to do some vision processing with OpenCV on a Raspberry Pi 3. I am a rank amateur so my meager efforts will not be of much help to anyone else. My idea is that … Continue reading

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Linux Tip: too lazy to write a startup script? how to fake it

Intro systemd can be pretty formidable to master. Say you have your own little script you like to run but you don’t want to bother with inserting it into the systemd facility. What can you do? The details A simple … Continue reading

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Raspberry Pi automates cable modem power cycling task

Intro I lose my Internet far too often – sometimes once a day. Of course I have lots of network gear in a rat’s nest of cables. I narrowed the problem down to the cable modem, which simply needs to … Continue reading

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Relative time with the linux date command

The situation A server in Europe needs to transfer a log file which is written every hour from a server in the US. The filename format is 20171013-1039.log.gz And we want the transfer to be done every hour. How we … Continue reading

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Fail2ban fails to work, I built my own

Intro I’ve sung the praises of fail2ban as a modern way to shutdown those annoying probes of your cloud server. I recently got to work with a Redhat v 7.4 system, so much newer than my old CentOS 6 server. … Continue reading

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