Friday, April 28, 2017

GlusterFS concepts and Architecture

I have made a presentation at GlusterFS meetup about GlusterFS - Concepts and Architecture:

You can access slides from here:

For trying out GlusterFS in CentOS, you can use this:

You can join the meetup for gaining more knowledge about GlusterFS:

Sunday, April 16, 2017

OpenShift origin installation issues and fix


# Add a entry for master node and slave nodes in /etc/hosts m1    c2    c1

# setup OpenShift cluster
ansible-playbook byo/config.yml 

# faced this error
fatal: [m1]: FAILED! => {"changed": false, "cmd": ["oc", "create", "-n", "openshift", "-f", "/usr/share/openshift/examples/image-streams/image-streams-centos7.json"], "delta": "0:00:00.181546", "end": "2017-04-16 23:59:08.477861", "failed": true, "failed_when_result": true, "rc": 1, "start": "2017-04-16 23:59:08.296315", "stderr": "Unable to connect to the server: x509: certificate signed by unknown authority", "stdout": "", "stdout_lines": [], "warnings": []}

# check differences between these two files - there are few differences, especially master's IP vs hostname

vimdiff /etc/origin/master/admin.kubeconfig  /root/.kube/config

# remove kube config file
mv  /root/.kube/config  /tmp/

# setup OpenShift cluster again
ansible-playbook byo/config.yml 
Another error faced is:

TASK [openshift_master : Start and enable master]
FAILED - RETRYING: TASK: openshift_master : Start and enable master (1 retries left).
fatal: [m1]: FAILED! => {"attempts": 1, "changed": false, "failed": true, "msg": "Unable to start service origin-master: Job for origin-master.service failed because the control process exited with error code. See \"systemctl status origin-master.service\" and \"journalctl -xe\" for details.\n"}

2. When verified using journalctl -xe, following is the error:
 http: TLS handshake error from read tcp4> read: connection reset by peer

All the issues can be resolved by removing /root/.kube/config and rebuilding cluster using ansible-playbook again.



Wednesday, April 5, 2017

reset your display size to normal

To set your screen resolution back to normal, use xrandr like this:

$ xrandr -s 0
The “-s” option allows you to specify the size, and the “0″ parameter tells xrandr to reset the screen to its default size

Tuesday, March 28, 2017

Android storage access in PC - usb detection issues in Redmi Note

Redmi Note had some issue in getting detected in PC (while connecting via USB).

This app helped:

MIUI USB Settings

First ensure, USB debugging is enabled.

You need to go to additional settings -> Developer options[1] -> USB debugging.

Then Open this app and enable MTP.

Now, Android storage should be available in PC.

For getting Developer options, you need to click on MIUI version few times. (It will display how many times to click to get Developer options enabled).

yaml format

YAML is a markup language with many powerful features

Rule 1:
YAML uses a fixed indentation scheme to represent relationships between data layers. 
Each level consists of exactly two spaces. DO NOT USE TABS.

Rule 2:

key value pair using colon.

my_key: my_value


Rule 3:

list of items
- list_value_one
- list_value_two
- list_value_three

For existing files, You can convert tabs to 2 spaces by these commands in Vim::set tabstop=2 expandtab and then :retab.

The suggested syntax for YAML files is to use 2 spaces for indentation,