Author: Grzegorz Juszczak

Cloud Computing

OpenStack: How to Manually Delete Orphaned Neutron Port

Jan 30, 2016 by Grzegorz Juszczak 1 Comments , , , , , ,

openstack
From time to time, especially during testing and automated script tenant deployment, my OpenStack cloud installation gets disordered. Situations when I am unable to delete neutron port in Horizon dashboard are pretty common phenomenon, this most likely leads to problem with deleting network which the problematic port belongs to.
In such cases we may need to edit OpenStack database, which is MariaDB, and manually delete orphaned neutron port related record from MariaDB ports table.

Error: Failed to delete port
Error: Failed to delete port: Port d06e19fc-c637-402b-85a2-3519c69a1035 has owner network:router_interface and therefore cannot be deleted directly via the port API.

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Linux, Storage

GlusterFS Storage Setup on Two CentOS 7 Servers and Client

Jan 25, 2016 by Grzegorz Juszczak 5 Comments , , , , ,

glusterfs_logo
GlusterFS is a simple and easy to configure scalable network attached storage. GlusterFS is a distributed storage consisting of nodes (servers including storage bricks), which export their own local file system as a volume. Volumes can be mounted on client servers as a network storage using NFS and Gluster Fuse. GlusterFS provides failover, redundancy and anti split-brain mechanisms that act as a High Availability system, that’s why in many aspects it is similar to the well known clustering software like Veritas Cluster Suite.

In this tutorial we will install GlusterFS on two CentOS 7 based nodes. We will use KVM Virtual Machines to make things easier and faster, but our main intention is to show you how to install GlusterFS on physical hardware.
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Linux

Upgrade from Fedora 21 to Fedora 22 using DNF

Jan 3, 2016 by Grzegorz Juszczak 0 Comments , , ,

fedora_logo
Starting from Fedora release 21 (Twenty One), Fedora can be upgraded using DNF system upgrade, which is recommended upgrade method for Fedora 21 and later releases. DNF is a kind of successor for FedUp (FEDora UPgrader), which is now obsolete, not supported any more by Fedora Project and should not be used in any circumstances.

In this article we will upgrade Fedora release 21 (Twenty One) to Fedora release 22 (Twenty Two) in five simple steps, using DNF system upgrade method.
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Linux, Virtualization

How to Install Docker on Fedora 23

Jan 3, 2016 by Grzegorz Juszczak 0 Comments , ,

docker_logo
Docker is a software which automates the deployment of applications inside Linux containers, by providing an additional layer of abstraction. This guarantees that it will always run the same, regardless of the environment it is running in. Docker uses the resource isolation features of the Linux kernel such as cgroups and kernel namespaces to allow independent containers to run within a single Linux instance, avoiding the overhead of starting and maintaining virtual machines.

In this tutorial we will setup and launch Docker software on Fedora 23 (64-bit) release.

Prerequisites for Docker installation on Fedora release:
Fedora version: Fedora 22 (64-bit) or higher
kernel version: 3.10 or higher
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Bash, Linux

ifdata – network interface information tool – ifconfig alternative

Dec 28, 2015 by Grzegorz Juszczak 0 Comments , , , ,

linux-terminal
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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Cloud Computing

OpenStack Liberty All In One Installation on CentOS 7

Dec 13, 2015 by Grzegorz Juszczak 47 Comments , , , , , , , , , , ,

openstack
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): 192.168.2.0/24
public network gateway: 192.168.2.1
node IP: 192.168.2.32
node OS: CentOS 7.1 64bit OS
node hardware: 2GHz CPU / 4GB RAM / 1 ethernet card
OpenStack version: Liberty
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Bash, Cloud Computing

OpenStack Command-Line Interface Cheat Sheet

Dec 5, 2015 by Grzegorz Juszczak 1 Comments ,

openstack
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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