Articles posted on 2013

Remote Bridging

Sometimes we need to connect two or more geographically distrubuted ethernet networks to one broadcast domain. There can be two different office networks of some company which uses smb protocol partially based on broadcast network messages. Another example of such situation is computer cafes: a couple of computer cafes can provide to users more convinient environment forr playing multiplayer computer games without dedicated servers. Both sample networks in this article need to have one *nix server for bridging. Our networks can be connected by any possible hardware that provides IP connection between them. Connecting Two Remote Local Networks With Transparent Bridging Technique Short description In described configuration we are connecting two remote LANs to make them appearing as one network with 192.168.1.0/24 address space (however physically, presense of bridges in network configuration is not affecting IP protocol and is fully transparent for it, so you can freely select any address space). Both of the bridging servers has two network interfaces: one (as eth0 in our example) connested to the LAN, and second (eth1) is being used as transport to connect networks. When ethernet tunnel between gateways in both networks will be bringed up we will connect tunnel interfaces with appropriate LAN interfaces with bridge interfaces. Schematically this configuration can be following: +-------+ +-------+ | br0 | | br0 | ...

Native Kerberos Authentication with SSH

This article is about integrating OpenSSH in a kerberos environment. Allthough OpenSSH can provide passwordless logins (through Public/Private keys), it is not a true SSO set-up. This article makes use of Kerberos TGT service to implement a true SSO configuration for OpenSSH. Pre-requisites First off, you'll need to make sure that the OpenSSH server's Kerberos configuration (in /etc/krb5.conf) is correct and works, and that the server's keytab (typically /etc/krb5.keytab) contains an entry for host/fqdn@REALM (case-sensitive). I won't go into details on how this is done again; instead, I'll refer you to any one of the recent Kerberos-related articles (like this one, this one, or even this one). Just be sure that you can issue a kinit -k host/fqdn@REALM and get back a Kerberos ticket without having specify a password. (This tells you that the keytab is working as expected.) ...

PHP notes

Notes on doing different things within the PHP language. Object oriented introspection property_exists(obj,prop_name) method_exists(obj,method_name) is_a(obj,'clas_name') or ($obj instanceof ClassName) ...

Getting rid of DRM on e-books and videos

Instructions on how to remove DRM from E-Books and videos. How to Remove DRM from Ebooks (and Back Up Your Library Permanently) The easiest way to strip DRM from Kindle books (and Barnes and Noble, Adobe Digital Content, etc) is with the free ebook software Calibre, DRM removal plugins, and a copy of the Kindle desktop software (PC/Mac). These directions are for Kindle, but will work with Barnes and Noble, Adobe Digital Editions, and older formats. Here's what you need to do: Download Calibre, the the plugins, and the Kindle Desktop software. Unzip the contents of the plugin directory. ...

Wordpress links

This article describes how you creeate hyperlinks within Wordpress. There are a number of ways to do this, depending on the configuration and the types of data we are linking to. Linking Without Using Permalinks This actually works whether or not Permalinks are active. Using the numeric values found in the ID column of the Posts, Categories, and Pages Administration, you can create links as follows. Posts ...

Makefiles

Some notes on GNU Make. I always have to look-up these in the manual. Here now for my own convenience. GNU Make automatic variables: From http://www.gnu.org/software/make/manual/html_node/Automatic-Variables.html. $@ ...

Cleaning up Google Calendar

Recipe for cleaning a google calendar. Sign in to Google Calendar Click on Calendar Settings (current version has this just above the list of personal calendars, under an arrow). Click on "Delete" of the main calendar. A confirmation dialog box appears telling you that that "This deletes all events on primary Calendar". ...

Automatically adding systems to an AD domain

When using virtualisation it is very common to create template VMs that can be cloned from. This makes deployment much easier than having to install a new VM from scratch. Unfortunately, the cloned VMs lack any Active Directory memberships and the VMs have to be manually added to the AD domain. For automated deployment scenarios this is less than desirable. This recipe intends to solve that issue in a ...

SATA/IDE warm plug/unplug

This is for SATA and IDE interfaces that do not automatically detect added/removed devices. Scanning for newly added discs: echo "- - -" > /sys/class/scsi_host/host0/scan safely removing a disk echo 1 > /sys/block/sda/device/delete ...

Icons

Finding icons: iconfinder. In 2023 I am using: icons8 This allows to download icons in different formats, and also allows you to do tweaks such as: ...

On-line Web Authoring Resources

A collection of links for Web-Authoring. This focuses on using Web (HTML and CSS) technologies directly and not through a CMS like Wordpress. http://www.webestools.com/ Free online tools, generators, services, scripts, tutorials. ...