Profile

Cover photo
고준
Lives in Seoul, Korea
99 followers|383,253 views
AboutPostsPhotosYouTube+1's

Stream

고준

Shared publicly  - 
 
Finding PID for programs - Why 'pidof foo' is less trustworthy than 'ps -eF | grep foo'
I often use pidof to find the PID of a running program. It works well with dhclient, dnsmasq and other executable binaries. But pidof runs into problems when trying to find the PID of script files that in turn invoke other programs. Take, for example, the P...
1
Add a comment...

고준

Shared publicly  - 
 
Differences in binary file sizes between RHEL and CentOS
CentOS maintains binary compatibility with Red Hat Enterprise Linux, so applications which run on certain versions of RHEL should be able to run without changes on analogous versions of CentOS. Recently, however, a client asked me why executable binaries fr...
1
Add a comment...

고준

Shared publicly  - 
 
Enable PXE netboot in KVM guests for testing UEFI
Many sysadmins and infrastructure engineers use Oracle VirtualBox + Vagrant to quickly test new system configurations without actually having to test on bare metal. Virtualbox is very convenient and its host bridge networking just works out of the box, but ...
1
Add a comment...

고준

Shared publicly  - 
 
Openstack with SELINUX
Normally before installing Openstack (be it Devstack, RDO, or some other flavor) I set SELINUX to permissive or disabled. Yesterday, however, I was at a client IDC and they requested that SELINUX be enabled before installing RDO 6 Juno. This was the first t...
Normally before installing Openstack (be it Devstack, RDO, or some other flavor) I set SELINUX to permissive or disabled. Yesterday, however, I was at a client IDC and they requested that SELINUX be enabled before installing ...
1
Add a comment...

고준

Shared publicly  - 
 
Problems compiling motion 3.2.12 on Fedora 24
I recently upgraded from f23 to f24 as soon as the latter was released. There are quite a few packages from the RPM Fusion community repo which are not yet available on F24 that are available on F23. When compiling motion the first issue I encountered after...
I recently upgraded from f23 to f24 as soon as the latter was released. There are quite a few packages from the RPM Fusion community repo which are not yet available on F24 that are available on F23. When compiling motion ...
1
Add a comment...

고준

Shared publicly  - 
 
Opening Ports for Openstack in Firewalld
Last week I made a post about opening ports in Ubuntu's ufw firewall when using Devstack (Openstack upstream). Today I will show you how to do the same thing in firewalld dynamic firewall which is now the default in RHEL 7+ and Fedora. The ports to be opene...
1
Add a comment...
Have him in circles
99 people
Saud Al-Farhan's profile photo
Enyjane Cuarte's profile photo
Travis Randall's profile photo
João Carvalho's profile photo
Imagine “IMAGINE LE MONDE” LE MONDE's profile photo
George Krompacky's profile photo
Jed Tibon's profile photo
seok won lee (테크홀릭)'s profile photo
Cameron Ken's profile photo

고준

Shared publicly  - 
 
Web scraping using lynx and shell utilities
In 2016, many people would probably think of using Python modules such as BeautifulSoup , urllib , or requests for scraping and parsing web pages. While this is a good choice, in some cases it can be quicker to scrape web pages using the text browser lynx a...
1
Add a comment...

고준

Shared publicly  - 
 
RHEL 5.X, 6.X - Converting RHEL to CentOS using shell scripts and Python 2
A client recently asked my company to help them convert Red Hat Enterprise Linux 5.11 and 6.8 to the comparable versions of CentOS. Before I present the scripts I wrote to automate this process, I believe that there is a lot of value in a RHEL subscription ...
1
Add a comment...

고준

Shared publicly  - 
 
PXE netboot installation differences between Ubuntu and RHEL
PXE netboot is the preferred method for fully automated/unattended installations of Linux to many machines at once. I have written several posts about PXE netboot for Linux, this one (PXE for UEFI and Legacy BIOS) being the most recent. In the RHEL world, f...
1
Add a comment...

고준

Shared publicly  - 
 
Google Cloud Platform billing shock (or don't forget to delete networking resources, too!)
I have played with public cloud services on AWS, Digital Ocean and recently, Google Cloud Platform (GCP). GCP is has a user-friendly, clean interface. One thing I really like is that estimated usage charges appear on-screen when you launch a compute instanc...
I have played with public cloud services on AWS, Digital Ocean and recently, Google Cloud Platform (GCP). GCP is has a user-friendly, clean interface. One thing I really like is that estimated usage charges appear on-screen w...
1
Add a comment...

고준

Shared publicly  - 
 
irssi 0.8.18+ SASL / SSL authentication config
As of v0.8.18, irssi irc client has native support for SASL (Simple Authentication and Security Layer). Because  irssi  < 0.8.18 didn't have SASL support, the old workaround was to copy the Perl script  cap_sasl.pl  to  ~/.irssi/scripts/autorun/  . My old i...
1
Add a comment...

고준

Shared publicly  - 
 
Openstack - List of ports which must be opened in the firewall
I must confess that when testing new Openstack releases on a variety of different Linux distros (RHEL, Fedora, Ubuntu) I often disable the firewall in the interests of expediency. While this might be OK for internal testing in a lab environment or while pre...
1
Add a comment...
People
Have him in circles
99 people
Saud Al-Farhan's profile photo
Enyjane Cuarte's profile photo
Travis Randall's profile photo
João Carvalho's profile photo
Imagine “IMAGINE LE MONDE” LE MONDE's profile photo
George Krompacky's profile photo
Jed Tibon's profile photo
seok won lee (테크홀릭)'s profile photo
Cameron Ken's profile photo
Places
Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Seoul, Korea
Previously
Columbus, Jeju
Links
YouTube
Contributor to
Story
Tagline
Linux System Engineer, programming enthusiast
Work
Occupation
Linux System Engineer
Basic Information
Gender
Male
Other names
Peter, 정준
고준's +1's are the things they like, agree with, or want to recommend.
God, good guys and guns
www.economist.com

HOSPITABLE, diminutive and currently reliant on a wheelchair, Brenda Stevenson, pastor of the New Outreach Christian Centre in Charlotte, No

One Port to Rule Them All! | Linux Journal
www.linuxjournal.com

I was chatting with Fred Richards on IRC the other day (flrichar on freenode) about sneaking around hotel firewalls. Occasionally, hotels wi

diff -u: What's New in Kernel Development | Linux Journal
www.linuxjournal.com

When you run a program as setuid, it runs with all the permissions of that user. And if the program spawns new processes, they inherit the s

What UBC has learned about doing MOOCs | Tony Bates
www.tonybates.ca

Engle, W. (2104) UBC MOOC Pilot: Design and Delivery Vancouver BC: University of British Columbia. The University of British Columbia, a pre

Your visual how-to guide for SELinux policy enforcement | Opensource.com
opensource.com

Dan Walsh of Red Hat shares a visual how-to guide for SELinux policy enforcement.

Not So Spooky: Linux "Ghost" Vulnerability
blog.trendmicro.com

The recent GHOST vulnerability in Linux is difficult to exploit and has a limited attack surface.

The Cow Says, Have Fun! | Linux Journal
www.linuxjournal.com

Sometimes, when the clock hits 3:00am, and you've been in the server room since 9 o'clock the previous day, you start to get a little batty.

Computer Networking, TCP/IP Basics
xahlee.info

This page is a condensed intro to TCP/IP. It is written for programers or scientists who wants a quick understanding how TCP/IP works. In 2

Working with Stdin and Stdout | Linux Journal
www.linuxjournal.com

Previously, I erroneously titled my column as "SIGALRM Timers and Stdin Analysis". It turned out that by the time I'd finished writing it, I

Monitoring Android Traffic with Wireshark | Linux Journal
www.linuxjournal.com

The ubiquity and convenience of smartphones has been a real boon for getting information on the go. I love being able to jump on a Wi-Fi hot

Linux Foundation Certified System Administrator
training.linuxfoundation.org

Learn from the best with training from the Linux Foundation. Our comprehensive Linux training includes online, classroom, and corporate trai

Learn from the best with training from the Linux Foundation. Our ...
training.linuxfoundation.org

Learn from the best with training from the Linux Foundation. Our comprehensive Linux training includes online, classroom, and corporate trai

It Actually Is Rocket Science | Linux Journal
www.linuxjournal.com

I've never once made a model rocket. I've always wanted to, but apart from "tube with explodey rocket part", I really didn't know where to s

Google Noto Fonts
www.google.com

Beautiful and free fonts for all languages. Noto is Google’s font family that aims to support all the world’s languages. Its design goal is

The Indie Bubble Is Popping.
jeff-vogel.blogspot.com

Writing this article really stressed me out. I reworked it over a dozen times. To calm down a little, I will intersperse this with image tha