Tag: Linux

LDAP and Apache Basic Auth – how it works and how it doesn’t work

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Let’s imagine you work on an organization which uses Active Directory (just kidding, is there anyone who doesn’t …?) and on which people are forced to comply with draconian security policies, such as changing you strong password every N days (replace N for any number less than 30… why don’t people understand that it is harder for people to memorize a new strong password, than machines to brake them). Anyways, having a central location for all authentication purposes is, from any point of view, a good idea, even if coming from Microsoft :). If your organization already has in place …

Problems of replicating Virtual Machine

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One of the biggest advantages of VMs, is the capability of cloning and replicating them. This allows the creation of a number of similar systems, without having to replicate the configuration and installation time. Unfortunately , there are a small number of downsides: The MAC addresses are also cloned. Remember to generate new MAC addresses on each new cloned VM. Also, Ubunto caches this value, which will generate a typical error message on dmesg: “udev: renamed network interface eth0 to eth1” . To avoid this problem, delete the the file /etc/udev/rules.d/70-persistent-net.rules and restart the system.

How to manage a small Virtual Machine infrastructure

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Over the last months, I felt the need to start a small virtual machine infrastructure to manage every small need on a laboratory at work. The set up infrastructure is the following: 1x Apple Macbook Pro 4.1 – for development of the appliances 2x HP DL360 with 8GB RAM running Ubuntu 10.4 – to run the VMs Note that is this NOT a production environment. This only covers a LAB needs and requirements, so stuff like redundancy and fail safe will not be included.   Ad Over the next few weeks, I’ll add some important notes.   Workflow The workflow …

HTC Magic tethering with Linux and OSX Snow Leopard without Android’s root permissions

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Editor’s Note: Unfortunately, my HTC died just before I finished posting this, so not all steps were thoroughly tested although I did test the end results on both Snow Leopard and Linpus. For all those still waiting for HTC to update it’s Magic smart phone to Android 2.2, where not a lot of options for tethering you device with Linux or OSX machines: root it, pay for PDAnet (and it only works on OSX), or follow the following steps 🙂 How it works Android 1.6 doesn’t offer any capability to use a cell phone as a simple UMTS Modem, as …

Generating random files

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Why on earth would someone want to generate files of random content (not files with random name) ? Well, there is one big reason to do it: generate incompressible files. This seems a small reason, but there are a number os usage scenarios (apart from proving that random content is incompressible), most focus on transmitting files. Although is transparent to most people, but some tools do background compression namely, https, IPSEC and SSL VPNs, etc, and as such, trying to measure real world performance on those require incompressible content. First, how to generate it (assuming you can talk *NIX) ? …

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