SSH: Remove identified keys by hostname

Failed to connect to the host via ssh.

Have you ever seen such a error which is "Failed to connect to the host via ssh." on your terminal when connecting a host via ssh. It should be happened if known_hosts file is taken a wrong identified keys belonging to the host.

$ ssh foobar@foobar.com
Failed to connect to the host via ssh.

-R hostname

To clear the problem you may take away the identified keys with ssh-keygen command.

$ man ssh-keygen

...
-R hostname
        Removes all keys belonging to hostname from a known_hosts file.  This option is useful to
        delete hashed hosts (see the -H option above).
...

Use f option to specify a known_hosts files.

$ ssh-keygen -f ~/.ssh/known_hosts -R foobar.com
# No more
# rm -f ~/.ssh/known_hosts

That's it! :)

GopherCon 2016 - A recap

I had the opportunity to attend GopherCon 2016 in Denver. It's been an amazing week at the Colorado Convention Center.

I attended to very interesting talks during the two days of the actual GopherCon. Here is a recap of several impressed talks:

Talks

Understanding nil - Francesc Campoy

The opening keynote was by Francesc Campoy who doesn't need any introduction because he is the one of the Google Cloud Platform Podcast Hosts. He started his talks about understanding nil in Golang. Please check it out to understand what nil is.

Go for Data Science - Daniel Whitenack

Data Scientist codes Python to analyze some data and modeling. Go for Data Science tells that it's possible to code Golang for analyzing.

Don't Just Check Errors, Handle Them Gracefully - Dave Cheney

See this article

The Go Gopher: A Character Study - Renée French

Renée French is creator and designer of the Gopher. She talked with the Gopher character. Especially how does he hold that champagne glass (that image is familiar by the GopherGala.

Practical Advice for Go Library Authors - Jack Lindamood

Practical Advice for Go Library Authors

Panel Discussion - Dave Cheney (Moderator)

Hack a Day!

On the last day of the GopherCon, there was an optional hack day with hackathons and workshops carried out.

---

We absolutely can't wait for GopherCon 2017 in Denver!!

Debian 8 - Install latest version of MySQL server

Debian distribution provides MySQL 5.5, not 5.6 or later.

Here’s how to install latest MySQL server:

Install the MySQL APT repository config tool

MySQL :: Download MySQL APT Repository

# Download the MySQL APT repository config tool
wget http://dev.mysql.com/get/mysql-apt-config_0.7.3-1_all.deb

# Apply config tool to APT repository (as root)
dpkg -i mysql-apt-config_0.7.3-1_all.deb

# Update APT repository (as root)
apt-get clean && apt-get update

Configure the MySQL APT if you change default configurations.

Install the MySQL server/client

apt-get install mysql-server
apt-get install mysql-client

That's it!

Hello world

Hi there. I'm in Denver, Colorado.

#include 

int
main(int argc, char* argv[])
{
    printf("Hello world\n");
    return 0;
}