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Showing posts from July, 2014

(Ab)using Samba and inotify to implement simple menu of privilegedactions [Part 3: Basic Implementation]

Okay, so I got it working; but more as the first-generation system that I sketched out in my design notes. Ie. one trigger maps to one action, and there is no separation between objects and actions. When I set it up and gave it to my client to try out, she send me a text message with some feedback; it said "That's cool!", I'm happy. I dare say this will get a (little) more polished in subsequent deployments; it would be good to separate the configuration from the application logic.

Here is what it looks like in action; note that this is done over CIFS, so the reactivity of the interface will depend on whether Samba on the server, and you CIFS client, handles update notifications. For example, on my aging RHEL 6 GNOME 2 desktop, it does not (I have to hit refresh repeatedly); but I gather from my client's Mac, it does. You can see what it looks like from Windows from this tiny screencast I made:



Capturing and Analysing DNS Samples (tcpdump meets SQLite3)

A few nights ago, I was on a bit of a mission to determine how much traffic our servers were sending to our DNS servers, as I was fairly sure it was much, and I wanted to put some improvement in place so we don't make an issue for ourselves.

I didn't want to turn on query logging, because of the rate of traffic, and its not my job to manage the DNS service, but I can see the queries in flight, so tcpdump was an obvious tool to use. But I didn't want to be awking, grepping, sedding, and generally bashing (pun intended) tcpdump output into whatever variety of reports I wanted, so I instead fed it into SQLite3.