Tuesday, April 14, 2020

Xcode Not Enough Disk Space to Install

I need to update my Xcode on my MacBook Air, it only has 128 GB Flash Storage, and it is hard to upgrade the storage, obviously it has limited free storage, so I need to free some spaces, deleting my old files.

But, even there is already 23 GB free storage, it keep complaining, not enough disk space.

After I had 26 GB free storage, I can continue the update.

Saturday, April 11, 2020

Raise/Lower Hand on Zoom Cloud Meeting

Raise/Lower Hand on Zoom Cloud Meeting is a very useful feature.

During online meeting, or online class using Zoom, not all participant can talk at the same time, sometimes the host will mute all participants, when participant want to interrupt, or asking something, so they need to raise the hand.

It seems like not all Zoom user have Raise/Lower Hand icon on the main window, the easiest way to do so is using short cut, for Mac user, the shortcut is: `option + y`.


Tuesday, October 22, 2019

Configure SELinux Policies for Web Server Write Permission

To allow web server to write into some file or directory in the linux file system when SELinux is enable, we need to set SELinux Policies, first install policycoreutils-python:


# yum install policycoreutils-python

And then for every file or directory which web server has write access, set the policy:


# semanage fcontext -a -t httpd_sys_rw_content_t "/path/to/directory(/.*)?"

With above command, "/path/to/directory" and sub directory will have httpd_sys_rw_content_t context, which allow http to write into file or directory.

Saturday, September 21, 2019

virt-install Using Open vSwitch Bridge in KVM

When creating VM with virt-install and attach bridge network using command:

--network=bridge=ovs-br0,model=virtio
if ovs-br0 is an openvswitch bridge network, this will fail:

ERROR    Unable to add bridge ovs-br0 port vnet0: Operation not supported
To fix thi, add virtualport_type=openvswitch :

--network=bridge=ovs-br1,model=virtio,virtualport_type=openvswitch

Friday, September 20, 2019

Install and Configure KVM on CentOS 7

Check Virtualization Technology (VT) is enabled in the BIOS:


# lscpu | grep Virtualization
Virtualization:        VT-x
Install KVM and other software:


# yum install qemu-kvm libvirt libvirt-python libguestfs-tools virt-install

Start and enable the service:

# systemctl enable libvirtd
# systemctl start libvirtd
Configure bridge network: consider using openvswitch (search in this blog) Create VM:

virt-install \
--virt-type=kvm \
--name centos7 \
--ram 4096 \
--vcpus=2 \
--os-variant=centos7.0 \
--cdrom=/var/lib/libvirt/boot/CentOS-7-x86_64-Minimal-1908.iso \
--network=bridge=ovs-br0,model=virtio \
--network=bridge=ovs-br1,model=virtio \
--graphics vnc \
--disk path=/var/lib/libvirt/images/centos7-min.qcow2,size=20,bus=virtio,format=qcow2
This will create a VM with two network interface.

Monday, August 19, 2019

Set Up Go Programming Environment for Mac OS X

To start programming with Go programming language, we need to install it, there are many ways to install go, for Mac OS user there is an easy way to install it, using Homebrew.

But, we need to install Xcode first, after that we can type the following command to install Golang using Homebrew:

NodeJS Boot Camp in Jakarta

Boot Camp AirPutih Jakarta

In this bootcamp, we will learn and practice how to build web application using NodeJS, including: