Sungju's Slow Life

Personal journal


  • Normal user process shows “root:root” permission in /proc//

    If you are seeing ‘root:root’ under /proc// for your process, it means the process is in Zombie state. #include int main() { pid_t pid; int i; for (i = 0; ; i++) { pid = fork(); if (pid > 0) { break; } else { exit(0); } } while (1) { sleep(1); } return 0;… Continue reading

  • How to convert Flac to MP3 on Mac

    To convert FLAG files into MP3, you can find many good commercial software. But, if you don’t have many files and just need a quick and cheap way, you can try the below instead. It requires to have MacPorts installed, but it’s just for installing ffmpeg. $ sudo port install ffmpeg Now, you just need… Continue reading

  • How to improve the nova storage performance

    If you are using KVM for virtualisation in OpenStack, you might notice some big slowness with the virtual storage. You can improve the performance by using the hypervisor’s volume group directly. You just need to create a volume group and specify that in /etc/nova/nova.conf. libvirt_images_type=lvm libvirt_images_volume_group= Continue reading

  • Some basic swift commands

    I’m not using Swift much, but there’s a time that I had to deal with this to troubleshoot a problem. Here’s the some commands to check Swift status. $ swift stat $ swift stat $ swift stat $ swift list $ swift list –prefix= $ swift –all download $ swift download $ swift download $… Continue reading

  • Popular slogans in Facebook’s culture

    Done is better than perfect Move fast and break things Stay focused and keep shipping This journey is 1 percent finished Continue reading

  • passwordless login via ssh in Mac

    You can access your remote ssh server without password by put your ssh key in remote. Step 1: generate a key if you don’t have already $ ssh-keygen -t rsa Use the default for all paths. Step 2: Copy the file to the remote server that you want to access. As Mac doesn’t have… Continue reading

  • How to setup debugging environment for RHEL packages

    It’s hard to set the debugging environment in a different machine as it has different packages installed in each systems. It’s really hard when we are talking about distributed packages as it requires lots of other libraries with separate debug info packages. So, I made a small application that you can use to set the… Continue reading

  • Managing VMware from command line

    Here are some commands that you can use to manage virtual guests from command line. To check currently running virtual guests: $ cd “/Applications/VMware” $ ./vmrun -T fusion list Total running VMs: 1 ….. To start a virtual machine, you can use below. $ ./vmrun -T fusion start “/Users/sungju/Documents/Virtual Machines.localized/mymachine.vmwarevm/mymachine.vmx” To stop a… Continue reading

  • How to install OpenStack on Fedora VM

    OpenStack requires a system that has the virtualisation feature, but you might want to test it on the virtual guest before actually install it in bare metal system. In that case, you can achieve it by enabling nested virtualisation feature in recent Linux distribution. You can find if your distro has that feature by checking… Continue reading

  • How to reload udev rules

    If you made changes in udev rules, you might want to reboot to apply the changes. But, there’s a simpler method than system reboot. It depends which version you are using. I’ll put RHEL5 and RHEL6 commands which might cover most scenario. In RHEL5 $ yum install udev $ udevcontrol reload_rules $ /sbin/start_udev $ udevtrigger… Continue reading

  • How to change Mac OS X hostname

    If you want to change your Mac OS X’s hostname from the default, you can use the following command. $ sudo scutil –set HostName If you are in the terminal, you need to restart the terminal to get the changed host name. Continue reading

  • packages you need to install for cinder virtualenv test

    cinder documentation says you need to install below packages in Fedora/RHEL, but it’s not working as some packages are missing. $ sudo yum install python-devel openssl-devel python-pip git libmysqlclient-dev libqp-dev I had to test one by one and below seems working perfectly. $ sudo yum install python-devel openssl-devel python-pip git mysql-devel libpqxx-devel Continue reading