Posts Tagged: linux

Gradle — Customize Startup Scripts for Java Applications

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OK, so you use Gradle to build your Java projects. And if you use the application plugin in Gradle then you get also the startup script generation so you can ship that straight into your prod servers. Thing is, the application plugin generates a “standard” script — which does include the classpath and a whole […]

Using OS-level Signals in Java for Monitoring

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For those of you familiar to monitoring Java applications, I’m sure the first thing that springs to mind is JMX. And I agree, that is a nice framework to provide various app insights for tracking and monitoring. The trouble with JMX though, if you haven’t got a system in place already to collect this data […]

Tracking Users Online — Part 2

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First release of this project on Github is now out there. And as promised in my “pilot” post of this series, this post will walk you through what went into this release and why. The project itself as you recall is available on Github in this repository: https://github.com/liviutudor/PixelServer. The version for this release is pixelserver-1.0.0 […]

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Quite a while back, (and I mean quite a while back, that’s been enough water under the bridge so I can now tell the story 🙂 ) I used to work for this guy who quite frankly was way out of his depth in the position he was in. He was my (and others’) boss […]

(Very Very Simple) Bash Script to Delete Old Log Files

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So here’s the deal: you have an application running on a Linux box which generates log files. And these files keep mounting up and grow and grow and grow in both number and size and you have start considering cleaning up old logs which you don’t use anymore. I know about logrotate, it’s an awesome […]

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CDN — The Basics — Part 2

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In the previous post, “CDN — The Basics — Part 1”, we got as far as looking at the situation where a load ballancer is employed in front of a set of identical web servers, and the DNS is handled externally by a dedicated DNS server, potentially in a different cloud/region/data center. As it has […]

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CDN — The Basics — Part 1

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I wish I could put a “1 out of N” at the end of this post title, however, I have no ideas how far this will go unfortunately; I do however realise that the more I go into details about this subject the more there is to be said about it. And what I have […]

Configure autofs auto.smb on Debian Linux

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Yet another post from my old website brought back to life — just as with the previous such posts, I hope this still stands. Nowadays I’ve moved most of my “infrastructure” to Amazon, I don’t have to use this anymore, but I remember at the time having to do a bit of research into this […]

Automating iptables on Debian Linux

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It’s interesting to dwell occasionally into researching how people are reaching my blog and what are they looking for when they do so. As you have seen so recently I have brought back a few old articles that seem to have triggered the attention of some people on the net — at least that’s what […]

Checking the Disk Quota #2

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This is similar to the previous disk quota exploit I mentioned, except that this time an attacker can exploit the inode quota on the disk. This quota defines how many files user can use/store on a disk/partition. If there is no capping on this value, a user process can occupy all the inodes available on […]

network pc monitors

Checking the Disk Quota #1

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This is again similar to the others above, except that this time an attacker can exploit the disk quota. This quota defines how much space a user can use/store on a disk/partition. If there is no capping on this value, a user process can try to fill up the disk space available in the system, […]

Checking the Memory Quota

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This is somehow similar to the one above, except that this time an attacker can exploit the memory quota. This quota defines how much memory a user process can allocate at a time. If there is no capping on this value, a user process can try to allocate all the memory available in the system […]

Linux Hacks — Process Quota

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One way an attacker might try to crash your machine is to exploit the process quota — more specifically to exploit the fact that a process quota is not set. The process quota defines an upper limit for the number of processes a user can run at any moment in time. If this is not, […]