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            <p>It aint over until the lady sings and she refused to do so because she wasn't so happy with the commenting system. Initially I had tried to use Disqus but it had an unspecified error while importing from wordpress. Then I tried to use intense debate. Using intense debate is kind of like going back to wordpress but it didn't happen cause their admin area is just pathetic. I simply could't find the javascript to embed into the template for use with Jekyll. &nbsp;So it was back to disqus and the unspecified error this time wasn't there. &nbsp;They probably had some site issues when I tried it out the first time.</p>
            <p>Earlier I mentioned running across a <a href="http://realjenius.com/2012/12/01/jekyll-category-tag-paging-feeds/">plugin</a> that did both categories and rss. Turns out that the RSS generated is for the &nbsp;categories which I am not using a the moment and I am not sure if I want to add it either. &nbsp;Besides Disqus comes with it's own feed for each comment thread so it's going to be very confusing to the visitor to figure out which RSS feed to subscribe to. The simple solution is to &nbsp;just place a rss template file at the root level. Being lazy; I copied and pasted from this <a href="https://github.com/snaptortoise/jekyll-rss-feeds/blob/master/feed.xml">template</a>.</p>
            <p><a href="https://s3.amazonaws.com/images.raditha.com/blog/images/2013/photos-old.png"><img alt="" class="aligncenter" height="211" src="https://s3.amazonaws.com/images.raditha.com/blog/images/2013/photos-old-t.png" title="The design prior to switching" width="400"></a></p>
            <p>Having done all this it was time to flip the switch - but on the photo blog. Yes, folks, all this time I have been concentrating on it because it's so much simpler and doesn't even have half the posts in this blog. The photo above is what it used to look like. Click through to the <a href="http://photos.raditha.com/">site</a>, to see what it looks like now.</p>
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The lady finally sings

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            A post that was originally written on Dec 28, 2010, but wasn't published, but being released now to clear up the draft folder before the switch to Jekyll. Since the post was written dm-cache has in fact made it's way into the main branch of the kernel.
            <p style="padding-left: 30px;">Windows has something called ReadyBoost - us linux users have been having half of what Readyboost provides for as long as flash drives have been in existence. That is we have been able to use a flash drive as a swap file for a long long time which is essentially what ReadyBoost does. But there is something more.</p>
            <p style="padding-left: 30px;">Part of ReadyBoost is the ability to store some of the frequently used data on disk on a flash drive. In other words, the flash drive acts as a disk buffer. Again this is nothing new, the linux kernel automatically uses all available RAM as a disk buffer. When applications ask for more memory the buffers are reduced. MS DOS also used to have disk buffering systems but they fell by the way side when Windows came into being before making a come back.</p>
            <p style="padding-left: 30px;">What the mainstream linux kernel doesn't have is the ability to use a flash drive as a buffer. Fortunately there is a third party kernel module called <a href="http://users.cis.fiu.edu/~zhaom/dmcache/index.html">dm-cache</a> that does provide this facility. What's sad is that beaurocracy has kept it out of the mainstream kernel for close upon two years.</p>
            <p style="padding-left: 30px;">The fact that the module hasn't been included in the main source tree means it hasn't been maintained. So the version that's downloadable from <a href="https://github.com/mingzhao/dm-cache">github</a> is compatible only with kernel versions upto 2.6.29. Let's see if there is a patch somewhere.</p>
            <p style="padding-left: 30px;">References: http://en.wikipedia.org/wiki/ReadyBoost</p>

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Using a CF card as a disk buffer

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            Still stuck here on wordpress, need to clean out the drafts folder before flipping the switch for Jekyll. There were 23 drafts in all Some more than six years old! Only one or two are worth preserving. Here is one, that was originally written on Nov 22, 2008 but never published. This was part of my Quadruple play at home scenario. This device in question was taken out by lightening some time later.
            <p style="padding-left: 30px;">You can get started with the SPA 3102 telephone adapter by plugging in your phone and dialing '****'. Then you are connected to an IVR and you can make many changes such as define PPPoE connections etc. But one thing that you can't do is to change the LAN IP address. It's set by default to 192.168.0.1 .</p>
            <p style="padding-left: 30px;">My home network the IP address range is 192.168.1.0/255.255.255.0 so I had to create a virtual interface (eth0:1) and assign and IP in the 192.168.0.0 network before I could connect to it. Another option would have been to use the IVR to set the WAN port to obtain it's IP address via DHCP but then I wasn't sure if the device would run the web based admin panel through the external interface so I didn't even bother to try. Later on I found that you can use the '7932' code in the IVR to enable/disable this feature. Much easier to create eth0:0 , login, change the LAN IP on the device to my network and then to delete the eth0:0 again.</p>
            <p style="padding-left: 30px;">Since my router is actualy my desktop (with to NICs connected to it). I asigned another IP in the 192.168.1.0 network to the external interace on the telephone adapter. The moment I did that my entire network stopped working and the switch started blinking like crazy. It took a me a few minutes even to figure this out. I eventually reached the conclusion that whatever packets that were coming in through the internal interface it was sending out again through the external interface int he mistaken belief that those packets should be NATed this leads to a flood. I suppose this is akin to the 'howling' you hear when a mic is placed in front of a speaker.</p>
            <p style="padding-left: 30px;">I was really struggling to get the voice adapter to connect to my Asterisk. It was only after a lot of frustration that I figured out that the Asterisk server's IP has to be entered as in the proxy field (in the line 1 tab</p>

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Monthly Archives for 2013 03

The lady finally sings

Using a CF card as a disk buffer

SPA 3102 Getting Started