Understanding APT

APT - Advanced Package Tool is a tool in Debian based distros to install applications by fixing missing dependencies and also helps removing them when not required. The command-line utility apt-get is frequently used, while Synaptic is the GUI for the same utility. 

Recently, I encountered an issue with APT. I was trying to install Postgresql by running - 

 sudo apt-get install postgresql 

when it threw a bunch of errors as shown below -

Postgresql Error

So I decided to download the package list from the repositories mentioned in  /etc/apt/sources.list  to obtain the newest version of the packages by running the command:

 sudo apt-get update 

To my surprise, the above command failed to obtain the list by throwing up the below error:

Update failed

I tried to fix the issue by running the command -

 sudo apt-get install apt-transport-https 

and yet another bunch of errors:

Missing Package

Seriously, not my day to install Postgresql. I look up the errors trying to figure out a solution, but unfortunately, I don't find a solution. Instead, I find lots of similar issues. I was told that my sources.list is trying to use https instead of http for obtaining the package list. When I cross checked my sources.list file, I found no reference to https. The bug report showed that the issue is still open. I was determined to give up, but wanted to try one last time to try and fix all the errors. 

I backtracked the errors. So I started with the https issue. I fetched a new sources.list file and still the same error. I realized that maybe I should read what APT is saying. It says - 

Err http://ftp.us.debian.org/debian/ testing/main apt-transport-https amd64 1.0.9.5 404 Not Found [IP: 64.50.236.52 80]

E: Failed to fetch http://ftp.us.debian.org/debian/pool/main/a/apt/apt-transport-https_1.0.9.5_amd64.deb 404 Not Found [IP: 64.50.236.52 80]

I first try to ping the IP but ping failed. So I open a browser and manually track http://ftp.us.debian.org/debian/pool/main/a/apt/. When I search for the package apt-transport-https_1.0.9.5_amd64.deb, it is missing. On close analysis, I find that apt-transport-https_1.0.9.6_amd64.deb is found instead. So I download the new version and manually install it by running the command:

 sudo dpkg -i apt-transport-https_1.0.9.6_amd64.deb 

It installs without a fuss. Finally! So time to update. Now I run, 

 sudo apt-get update 

and it works. I installed postgresql and everything is back to normal. 

Although, I am surprised why APT acted crazy with the update command and pointing to an obsolete package. I'm yet to find the reason and when I do, I might probably write another post.

Until then, it's Just another day in the GNU/Linux world :)

Tor - Solution for low ulimit

Tor (The Onion Router) is a free software which provides online anonymity. More information about the tor project can be found at TOR. This post is specific to the Tor Browser Bundle in Debian based systems. 

The tor browser is started by running the command from the command line. However, sometimes the browser fails to load on account of ulimit being low. What this means is that, the minimum number of file descriptors required for tor browser to start is not available. 

  [warn] raise your ulimit -n  

When you see a warning like what is shown above, check the current maximum value of file descriptors available by typing the command -

  ulimit -n  

If the value is less than 1000, it is required to raise the system default limit. In order to do so, navigate to /etc/security and edit the limits.conf file. Remember to edit the file as root. Add the following lines before the end of the file - 

*        hard        nofile        75000

*        soft        nofile        10000

The above two lines are used to set the value for maximum number of open files ( nofile ) as default entry ( * ). The values for hard limit and soft limit need not necessarily be what I have provided. It can be any value higher than the current value set as default by the operating system. After editing the file, save it, log out and log back in to see the changes reflected. Check by typing ulimit -n command again.  

Now, you should be able to start the tor browser from the command line. 

ComicCon 2014

Just when life gets monotonous, there'e one day to break the routine and enjoy the day. And that was ComicCon. A 3-day event hosted at White Orchid Bangalore, I went on the second day(Saturday). Needless to say, the crowd was overwhelming. Seeing cosplayers all over the place, posing for pictures and selfies, was a major highlight of the event B-) Let's get to that later. 

Many independent artists displayed their work that were well appraised. One particular booth that caught my attention was the Paper Cut Artwork. 

Papercut Artwork

Every design in the above image is made by cutting paper in different shapes. A skillful work that requires lots of patience. They accepted making custom designs on spot too. Brilliant work I should say =D> Another place I loved was the charcoal painting section. Had some really great work. 

Merchandises included T-shirts, pajamas, keychains, badges, wallets, bags, masks, mugs, posters, coasters, wall hangings, dolls, sunglasses, shoes, phone covers and I can't think of the rest :P Popular superhero stuff included Batman, Ironman, Superman and Hulk. Anime stalls were filled with people buying their favorite character posters, mugs and other merchandises. Harry Potter stall selling the snitch, sorting hat and wands were thronged by people atleast for taking pictures :)) The One ring, LOTR books with posters and T-shirts were a good collection too. Surprisingly, I couldn't find gollum posters or Tees anywhere :| Guy fawkes mask, V for vendetta book and Tees were sold too. Oh, how could I miss the legendary Star Wars? A dedicated star wars booth with light sabers and the droids. Posing by fighting with the light saber had a huge queue :P T-shirts of Sherlock with famous quotes and Sherlock images itself were sold. Again, couldn't find Watson quotes or T-shirts. Strange! Bazinga Tees, Mugs, keychains etc were found in most stalls along with Sheldon's quotes and posters. Somehow the other characters weren't found. Wonder why :-/ And finally, stalls with Game Of Thrones crafts. Found lots of quotes, posters, T-shirts, the book, a few memes and many more interesting stuff. 

Three sorry four places where people thronged the most were to get a free poster, a caricature, instaframe and face painting. Free posters for anyone filling a form to choose your favorite superhero or star wars character! B-) Caricature sketches by TaxiForSure was another interesting place. Artists sketched faces of fans on printed superhero torsos. There were two sketch artists with a long queue of fans. Instaframe was a photo booth to capture your image by wearing colored wigs :)) Instagram special I must say. Face painting (or so it was called) with superhero logos, symbols etc was another demand. And I got batman logo painted on my arm :P The patience these guys had to paint for so many people should be appreciated.  

Guests of the day. Met Rob Denbleyker, the co-creator of Cyanide & Happiness comics. He was more than willing to draw sketches on spot to dedicated fans. Dan Parent of Archie Comics was there too. Got an autograph from David Llyod of V for Vendetta. Took a photo with him too :P 

Coming to the highlight of the event. Cosplay! Special guests for the day to host cosplay were the boys from A!B. With their jokes and sarcasm, the event was lively. The event was started by professional Japenese Cosplayers Akira and Miya. Akira sang a Japanese song. Had no clue what she was singing or saying :| Finally, the cosplayers. These guys were all over the place from noon. The major cosplayers I came across were Scarecrow, Joker(very common), Prince of Persia, Khaleesi, Catwoman, Rapunzel, Jack Sparrow, V, Thor, Wall E, Bellatrix, Harry Potter, Sherlock, Wolverine, plenty of Anime characters (too many to mention :P), Neo, Minions, Ironman, Darth Vader and that's all I can remember :P Selfies and photos all over the place with the cosplayers :)) 

The major bummer of the event was lack of Network for 3G and WiFi :( Most of the time, calls/messages couldn't be received too. I think apart from that, it was a very nice experience. Amazing crowd! Met a lot of school friends and college friends :) After a very long time, I got to enjoy an entire day thoroughly. Hoping to pen another nice experience soon. Until then, see ya folks! :-h

My First Blog Post!

Hello! Finally, after a long time, I've decided to start blogging. Watch this space for new posts pretty soon. And for now,