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Posts Tagged ‘dns’

Top 10 things I have learned since the start of this experiment

October 2nd, 2009 4 comments

In a nod to Dave’s classic top ten segment I will now share with you the top 10 things I have learned  since starting this experiment one month ago.

10: IRC is not dead

Who knew? I’m joking of course but I had no idea that so many people still actively participated in IRC chats. As for the characters who hang out in these channels… well some are very helpful and some… answer questions like this:

Tyler: Hey everyone. I’m looking for some help with Gnome’s Empathy IM client. I can’t seem to get it to connect to MSN.

Some asshat: Tyler, if I wanted a pidgin clone, I would just use pidgin

It’s this kind of ‘you’re doing it wrong because that’s not how I would do it’ attitude can be very damaging to new Linux users. There is nothing more frustrating than trying to get help and someone throwing BS like that back in your face.

9: Jokes about Linux for nerds can actually be funny

Stolen from Sasha’s post.

Admit it, you laughed too

Admit it, you laughed too

8. Buy hardware for your Linux install, not the other way around

Believe me, if you know that your hardware is going to be 100% compatible ahead of time you will have a much more enjoyable experience. At the start of this experiment Jon pointed out this useful website. Many similar sites also exist and you should really take advantage of them if you want the optimal Linux experience.

7. When it works, it’s unparalleled

Linux seems faster, more featured and less resource hogging than a comparable operating system from either Redmond or Cupertino. That is assuming it’s working correctly…

6. Linux seems to fail for random or trivial reasons

If you need proof of these just go take a look back on the last couple of posts on here. There are times when I really think Linux could be used by everyone… and then there are moments when I don’t see how anyone outside of the most hardcore computer users could ever even attempt it. A brand new user should not have to know about xorg.conf or how to edit their DNS resolver.

Mixer - buttons unchecked

5. Linux might actually have a better game selection than the Mac!

Obviously there was some jest in there but Linux really does have some gems for games out there. Best of all most of them are completely free! Then again some are free for a reason

Armagetron

Armagetron

4. A Linux distribution defines a lot of your user experience

This can be especially frustrating when the exact same hardware performs so differently. I know there are a number of technical reasons why this is the case but things seem so utterly inconsistent that a new Linux user paired with the wrong distribution might be easily turned off.

3. Just because its open source doesn’t mean it will support everything

Even though it should damn it! The best example I have for this happens to be MSN clients. Pidgin is by far my favourite as it seems to work well and even supports a plethora of useful plugins! However, unlike many other clients, it doesn’t support a lot of MSN features such as voice/video chat, reliable file transfers, and those god awful winks and nudges that have appeared in the most recent version of the official client. Is there really that good of a reason holding the Pidgin developers back from just making use of the other open source libraries that already support these features?

2. I love the terminal

I can’t believe I actually just said that but it’s true. On a Windows machine I would never touch the command line because it is awful. However on Linux I feel empowered by using the terminal. It lets me quickly perform tasks that might take a lot of mouse clicks through a cumbersome UI to otherwise perform.

And the #1 thing I have learned since the start of this experiment? Drum roll please…

1. Linux might actually be ready to replace Windows for me

But I guess in order to find out if that statement ends up being true you’ll have to keep following along ;)

DNS Not Satisfactory

September 25th, 2009 No comments

While trying to connect to a remote webserver via SSH last night, I found that my machine refused to resolve the hostname to an IP address. I couldn’t ping the server either, but could view a webpage hosted on it. Now this was a new one on me – I figured that my machine was caching a bad DNS record for the webserver, and couldn’t connect because the server’s IP had since changed. That didn’t really explain why I was able to access the server from a webbrowser, but I ran with it. So how do you refresh your DNS cache in Linux? It’s easy to do in Windows, but the Goog and the Bing let me down spectacularly on this issue.

This morning, I tried to connect via SSH from my school network, and couldn’t get a connection there either. This reinforced the idea that a local DNS cache might have an outdated record in it, because at school, I was using a different nameserver than at home, and a whole 12 hours had elapsed. Out of theories, and lacking a method to refresh my local DNS cache, I hit the #debian channel on IRC for some guidance. Unlike my last two trips to this channel, I got help from a number of people within minutes (must be a timezone thing), and found out that unless I manually installed one, Debian does not maintain a DNS cache. Well, there goes that idea.

So where was I getting my DNS lookup service? A quick look at my /etc/resolv.conf file showed that the only entry in it was 192.168.1.1, which is the IP of my home router. The file also has a huge warning banner that claims that any changes will be overwritten by the operating system. Makes sense, as when I connect to a new network, I presumably get DNS resolution from their router, which may have a different IP address than mine. The guys on IRC instructed me to try to connect to the server with it’s IP address instead of it’s hostname, thereby taking the DNS resolution at the router out of the picture. This worked just fine.

They then instructed me to add a line to the file with the IP address of the nameserver that the router is using. In the case of our home network, we use OpenDNS, a local company with static servers. I did so, and could immediately resolve the IP of my remote server, and obtain an SSH connection to it.

Well fine, my problem is solved by bypassing DNS resolution at the router, but it still doesn’t explain what’s going on here. Why, if DNS resolution was failing at the router level (presumably because the router maintains some kind of DNS cache), did it work for my webbrowser, but not the for ssh, scp, or ping commands? Don’t they all resolve nameservers in the same way? Further, if it was the router cache that had a bad record in it, why did the problem also manifest itself at school, where the router is taken entirely out of the picture?

Further, will the file actually be overwritten by the OS the next time I connect to a different wireless network? If so, will my manual entry be erased, and will the problem return? Time will tell. Something smells fishy here, and it all points to the fact that my machine is in fact retaining a local DNS cache. How else can I explain away the problem manifesting itself on the school network? Further, even if I do have a local cache that is corrupted or contains a bad record, why did Iceweasel bypass it and resolve the address of the webserver at the router level (thereby allowing it to connect, even though the ssh, scp, and ping commands could not)?

LINUX!!11