## Error: NoValidHost: No valid host was found You get below error message on the console while performing an overcloud deployment from the undercloud director ``` 2018-08-14 06:42:59Z [overcloud.Controller.0.Controller]: CREATE_FAILED
**Below list of topics are covered in this article** * [Bring up undercloud director]({{< relref "openstack-tripleo-architecture-step-guide-install-undercloud-overcloud-heat-template/index.md" >}}#Bringupunderclouddirector) * [Prepare Undercloud for overcloud deployment]({{< relref "openstack-tripleo-architecture-step-guide-install-undercloud-overcloud-heat-template/index.md" >}}#PrepareUndercloudforoverclouddeployment) * [Phases of overcloud node deployment]({{< relref "openstack-tripleo-architecture-step-guide-install-undercloud-overcloud-heat-template/index.md" >}}#Phasesofovercloudnodedeployment) + [Registration]({{< relref "openstack-tripleo-architecture-step-guide-install-undercloud-overcloud-heat-template/index.md" >}}#Registration) + [Introspection]({{< relref "openstack-tripleo-architecture-step-guide-install-undercloud-overcloud-heat-template/index.md" >}}#Introspection)
In my last article I had brought up my undercloud setup from scratch. Follow below link to get the details
In the article we will cover below topics
We know there are various tools available which can help you get the memory related information from the system, some of them are listed below [](Everything2Byou2Bmust2Bknow2Bbefore2Byou2Bstart2Bworking2Bwith2Bsystemd2B2528122529.webp) Report short summary of
**Below list of topics are covered in this article:** * [Types of HugePages]({{< relref "enable-or-disable-transparent-anon-hugepage-thp-check-status-examples-linux/index.md" >}}#TypesofHugePages) * [How to disable Transparent Hugepages on runtime]({{< relref "enable-or-disable-transparent-anon-hugepage-thp-check-status-examples-linux/index.md" >}}#HowtodisableTransparentHugepagesonruntime) * [How to disable Transparent Hugepages permanently using GRUB2]({{< relref "enable-or-disable-transparent-anon-hugepage-thp-check-status-examples-linux/index.md" >}}#HowtodisableTransparentHugepagespermanentlyusingGRUB2)
Hugepages is a feature that allows the Linux kernel to utilise the multiple page size capabilities of modern hardware architectures. Memory is managed in blocks known as pages. A page
Below list of topics will be covered in this article * [Lock account using pam_tally2]({{< relref "how-to-lock-or-unlock-root-normal-user-pamtally2-pamfaillock-linux/index.md" >}}#Lockaccountusingpamtally2) + [Lock non-root user (normal user) for failed login attempts]({{< relref "how-to-lock-or-unlock-root-normal-user-pamtally2-pamfaillock-linux/index.md" >}}#Locknonrootusernormaluserforfailedloginattempts) + [Lock "root" user for
In this article I will show you the steps to configure an offline yum repository in your network using http server **IMPORTANT NOTE:** I had already written an aticle to
Earlier I had written an article on [**swappiness**]({{< relref "what-is-swappiness-and-how-do-we-change/index.md" >}}) and different commands to [**check memory usage per process**](https://www.golinuxcloud.com/check-memory-usage-per-perocess-linux/) on Linux here I will show you some of the methods which can