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Enable UEFI for QEMU KVM on Fedora

UEFI (Unified Extensible Firmware Interface) has become a successfull successor of an outworn and obsolete BIOS firmware. Emulating UEFI based hardware on KVM/QEMU Virtual Machine is possible thanks to so called OVMF (Open Virtual Machine Firmware), which comes from EDK2 (EFI Development Kit), UEFI reference implementation. OVMF is available as an RPM package for RPM based distros (CentOS, Fedora, Red Hat). In case of Fedora release all we need is edk2-ovmf RPM package.
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How to configure Docker Proxy on CentOS 7, RHEL 7

How to enable Proxy for Docker engine with or without authentication on CentOS 7, Red Hat Enterprise Linux 7?

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CentOS 7 Installation with LVM RAID 1 – Mirroring

CentOS 7 may offer us a possibility of automatic RAID configuration in Anaconda installer, that is during OS installation, once it detects more than one physical device attached to the computer. Mentioned RAID is generally the LVM-RAID setup, based on well known mdadm – Linux Software RAID. It’s a pretty convenient solution, since we don’t need to setup RAID manually after installation, on already running system.

The below procedure presents CentOS 7 testing installation with LVM RAID 1 (Mirroring) on KVM based Virtual Machine with two attached 20GB virtual disks.
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MariaDB high CPU usage in OpenStack Pike

Testing OpenStack Pike after Packstack based deployment I realised MySQL daemon was utilizing 100% CPU resources without any specific reason, but I had never faced such problem before in previous OpenStack releases. The problem also has never appeared during my TripleO based OpenStack Pike deployments, so looks like it’s strictly Packstack related issue.

The situation heppened on few bare metal installations on pretty powerful servers. Restarting mariadb service was helpful just for the first few minutes after service restart, then the problem would happen again and again, what resulted in frequent Horizon Dashboard and Keystone inaccessibility and partial Controller unavailability.
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OpenStack Pike VLAN and Flat network based installation using Packstack

In previous articles regarding OpenStack RDO installations we presented OpenStack deployments using Packstack automated installer script, which still required some post-installation networking configuration to be performed in order to accomplish whole deployment. This time we will try to prepare Packstack configuration file (answers.txt) in such way, that it does all the magic and no post-installation configuration is required. We will make full bridge:interface mapping so, that no further bridge setup is needed and the environment should be ready to use immediately after Packstack deployment.
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How to find qbr,qvo interfaces of the particular Instance in OpenStack

OpenStack networking topology is pretty complicated structure, even with it’s, let’s say, default configuration based on OVS (OpenVSwitch), not even mentioning about additional overlays, like OpenDaylight or Nuage.
If you are troubleshooting network issues in regard to a particular Instance (VM), it’s good to locate network overlay interfaces (qbr, qvo) assigned to that Instance to have a starting point to begin your network analysis from. You can then analyze inbound/outbound traffic on those interfaces using network protocol analyzers, like tcpdump/wireshark.

Below you can find few steps, how to locate qbr,qvo interfaces belonging to a particular Instance:
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