ifdata – network interface information tool – ifconfig alternative

ifdata is a quick, lightweight and simple tool to display network interface information in Linux, which can be used as an alternative for ip addr show or ifconfig.

Sometimes I want to quickly find out, if the particular network interface exists in the system or I want to display it’s IP address or MTU value only. If I used ifconfig for this case, I would have to parse the output using grep or other tools. ifdata resolves this problem in more sophisticated manner – it utilizes parameters to better control the output we want to obtain. This is another reason why ifdata is more friendly for use in BASH scripting.
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OpenStack Liberty All In One Installation on CentOS 7

In this tutorial we will install OpenStack Liberty release from RDO repository on one node (all-in-one installation) based on CentOS 7 / RHEL 7 using packstack installer script.

In all-in-one configuration all OpenStack nodes (controller node, compute node, network node) are installed on a single machine. This type of configuration can be deployed very easy and fast for testing purposes, also on KVM machines, when no physical hardware is available.

Environment used:
public network (Floating IP network):
public network gateway:
node IP:
node OS: CentOS 7.1 64bit OS
node hardware: 2GHz CPU / 4GB RAM / 1 ethernet card
OpenStack version: Liberty
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OpenStack Command-Line Interface Cheat Sheet

Openstack, besides Horizon GUI Dashboard, can also be configured via command-line interface using commands in Bash. Below we present a list of common and useful commands for your reference.

Note: in OpenStack command-line interface you have to source appropriate keystonerc file in order to be able to invoke OpenStack commands within the specified Project Tenant. Sourcing of keystonerc file imports Tenant User/Admin credentials to environment variables during user session.
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