Saturday, May 26, 2018

Setting Up Red Hat Virtualization with Single Server

Red Hat Virtualization is an interesting and powerful platform software, but it is rather challenging to setup with only a single host when compared to Hyper-V, VMware and VirtualBox. One may argue that RHEV is not design for single host (I guess that is why there is no single article about how to do the setup), but who really care if just want to use for a tiny scale deployment? Single host rules!



Well, I could go for RHEL + KVM, but I simply like the interface of RHEV.
Getting it up and running requires user to have experience from numerous area of expertise. This simplified guide is not for newbie.

Setting up the RHVH is not hard. I'm going to skip it. Now, in order to get the hosted-engine up and running, please make sure the following are done:

1. Change the hostname localhost.localdomain to hostname. In my case, I use robustpoc.
2. Be sure to set a fix IP in /etc/sysconfig/network-scripts/ifcfg-eth0 and reconnect using the new IP using ifdown eth0 and ifup eth0.
3. Edit /etc/hosts to resolve the host IP address to the hostname.
4. In order to make this IP change persistent, be sure to change the settings in /var/lib/vdsm/persistence/netconf/nets/ovirtmgmt

Note: If the server is in a VLAN Network, be sure to set a correct gateway otherwise it would not be able to connect to Internet or reach by others in the network.

5. Now, before proceed with executing hosted-engine --deploy, you require to add your FQDN to /etc/hosts. In my case, I use 192.168.0.26 robustpoc.com. This is critical.
6. Next, setup NFS share. Follow the guide below:



7. At this point, we are ready to execute hosted-engine --deploy.
Three critical settings to take note during the process:
8. Be sure NOT to set the memory of the VM to maximum available memory of the system as per suggested by the setup. Setting to maximum will lead to no available memory to create any single Virtual Machine.
9. Be sure to use a fixed IP for the engine. Make sure gateway is correct too.
10. Be sure to answer YES when asked whether to update the /etc/hosts for both the host and engine VM. The default answer is NO. Missing out this would be a killer later.

Until this point, everything critical should have already been taken care of. Cross finger and I wish you the best luck!

Common errors that I have encountered but do not guarantee to happen:
1. Error: [Get Local VM IP] failed
2. Info: [Waiting for local VM to be up]
3. [ ERROR ] Failed to execute stage 'Closing up': Failed executing ansible-playbook; then I can access to RHEV Manager but an failed external hosted engine present in the Compute > Hosts.

Welcome to share with me your installation experience, I'm happy to listen and learn from you.