Virtualization hypervisor and containers all in one

I’m a big fan of virtualization, the ability to run multiple platforms and operating systems (called guests) in a single server (called host) is probably one of the best computing technologies of the past 10 years.

Personally, I have been using virtualization circa 2004. It all took off after 2006 when chip manufacturer’s started bundling virtualization technologies in their processors (Intel VT-x or AMD-v). The reason why “cloud” computing is so popular can also be attributed to virtualization.

In a container world…

However, in the past couple of years a new technology has been making making the rounds everywhere, the words “containers”, “docker”, “orchestration” is picking up steam in the past year. They say that containers are changing the landscape for system administrators and application developers.

Claims that containers can be built and deployed in seconds, share a common storage layer and allow you to resize the container in real-time when you need more performance or capacity are really exciting concepts and I think the time is now for me to jump in and learn a thing of two about this new technology when its hot a new.

Time to ditch vmware ESXi for a hybrid hypervisor?

You may remember my blog entry building a low-power sandy bridge ESXi server with ZFS – now 5 years later it is time to find a new platform that will allow me to keep my legacy virtual machines (VMs) as well as allow me to host containers using Docker.

The process of finding a suitable replacement for ESXi may take awhile and more than just a single entry on my blog. This is the first entry on my journey.

Before replacing something that works with a new platform I think it is good to point out the strengths and weaknesses of vmware ESXi (which has been my platform of choice for 6 years)

Strengths of ESXi

• awesome windows GUI vSphere client that allows you to manage your hypervisor without the need for console or ssh
• a web-interface to manage it too if you install a plugin
• virtual switch with VLAN support
• support for PCI passthrough (Intel VT-d) allowing you to assign PCI devices to virtual guests

Weaknesses

• does not support docker containers (unless you wish to create a virtual machine and run docker from there – but I prefer a central platform if possible)
• vmware continues to remove features from the free version of ESX – vSphere client interface is no longer availabel in their latest release
• Nothing exciting has been released by vmware in the past 2 years (in terms of ESXi) and they push esxi users into paid licensees

The alternatives?

SmartOS is a fork off OpenIndiana/OpenSolaris, it seems to have a lot of great security features and features from Solaris that enjoy (you may have read of my love for the ZFS filesystem which is native to SmartOS). Joyent has recently open-sourced their SmartDataCenter “SDC” or they are now calling it Triton Enterprise.

What I like about it other than the fact it uses native Solaris and it uses the ZFS filesystem for storage is the fact that it is a hybrid hypervisor. It can host containers and VMs (using technology similar to virtualbox since virtualbox is also from solaris).

The downside of this platform seems to be the complexity needed to deploy containers with this tool. You need to have a “head node” to be the brains of the platform, the “head node” does a lot of critical things. It monitors the network, the other compute nodes (where you host your vms/containers), it also hosts the database for all the nodes. In dev mode you can force the head node to also be able to host VMs but this is not recommended or good practice.

The web interface (SmartDataCenter) to manage your containers and VMs is also very rudementary, there is no built-in console to your guests. You need to run a lot of commands in the head node’s shell to make JSON queries to grab the data you want like the VNC server and port address for your guests.

Honestly I have not dug much deeper into SmartOS but I probably should, it looks like an awesome project. I am sure for people that want to use their platform for scalable container/hypervisor deployments it makes sense, but to replace my single server at home doing virtualization it does not look very likely this may be a good choice given the complexity.

Proxmox is another platform I am looking at, you may recall that 7 years ago I discovered proxmox virtual environment and started using it on my lab. That was Proxmox VE 1.5 I think and I recently discovered they have made a lot of strides in the right direction.

Just a few weeks ago they released their latest PVE 4.4 and they are now supporting ZFS data pools (via FUSE/zfsonlinux), not to mention that they have replaced OpenVZ with LXC (linux containers). It may be worth it for me to download their latest release and check out their platform again.

Other than Proxmox or SmartOS, I have not come across any other ‘hybrid’ hypervisors. Please share in the comments if there is something else I should check out.