On April 17, 2018, VMware released vSphere 6.7. This includes vCenter, ESXi, and of course vSAN. A lot of people are looking to upgrade in order to take advantage of the new features, and enhancements; primarily the H5 client… good bye flash client! Links to more info on what’s new for vSphere and vSAN.
From an HMTL 5 client perspective, the feature parity is about 95%. For vSAN alone, it is about 99%, as we are only missing Configuration Assist, which is still available via the flash client.
I see a lot of people getting confused, and still believe that vSAN is a separate upgrade, just like traditional storage. Fortunately, vSAN is in the kernel, so once you upgrade ESXi you have also upgraded vSAN. Boom!!! Even though the version numbers may not be exact between ESXi and vSAN, they still go hand-in-hand. With that, it is important to understand the steps necessary for a vSAN upgrade.
Based on the nature of vSAN, we need to follow the vSphere upgrade path. This includes checking the VMware Product Interoperability Matrices, not only with your current versions against the versions you are going to upgrade to, but also all the other VMware products such as NSX, SRM, vROps, etc.
Upgrade Process Overview
From an upgrade process perspective, you have options. You can migrate your Windows vCenter to the vCenter Appliance (recommended). If you already have the vCenter Appliance, you can either do an in-place upgrade, or create a new vCenter if you want to migrate your hosts over to a fresh new vCenter install. Here is more info on vSphere upgrades.
Upgrade, Migrate, or deploy new vCenter
Depends on current version
This will also upgrade vSAN (easy, right?)
Upgrade vSAN on-disk Format (ODF)
Upgrade VMware tools
As previously discussed, you will need to check the Product Interoperability Matrix to make sure all your products can run on vSphere 6.7. Don’t shoot from the hip, and start upgrading before you have done proper research.
I mentioned the choice of migrating hosts to a new vCenter. This is something I do quite often in my labs, and it is a simple process.
Migration Process Overview
Export vDS configuration (including port groups)
Copy licenses from old vCenter
Configure new vCenter
Create Datacenter in vCenter
Create a Cluster and enable vSAN on it
If you currently have other services enabled, they will have to be enabled on the new vCenter as well prior to moving the hosts.
Assign license to vCenter
Assign vSAN license to cluster asset
Create vDS on the new vCenter
Import configuration and port groups to new vCenter
On the new vCenter, add hosts
No need to disconnect hosts on the old vCenter, they will disconnect after connecting to the new vCenter.
Confirm ESXi license or assign a new one.
Connect the hosts to the vDS (imported)
Make sure you go through and verify assignment of uplinks, failover order, vmkernel ports, etc.
Lastly, you will need to tell vSphere that this new vCenter is now authoritative
In previous posts, I talked about vSAN Encryption architecture, and how to enable such feature. However, there are a couple of considerations aside from the requirements that should be taken into account prior to enabling vSAN Encryption.
With most deployments, whether it is vSphere, or vSAN; I’ve noticed that BIOS settings are often overlook, even though they can help increase performance with a simple change. One of those settings is AES-NI. AES-NI was proposed by Intel some time back, and it is essentially a set of [new] instructions (NI), for the Advanced Encryption Standard (AES); hence the acronym AES-NI. What AES-NI does, is provide hardware acceleration to applications using AES for encryption, and decryption.
Most modern CPUs (Intel & AMD), support AES-NI, and some BIOS configurations from certain hardware vendors already have AES-NI enabled by default. When considering vSAN Encryption, it is imperative to make sure that AES-NI has been enabled in the BIOS, in order to take advantage of such offloading of instructions to the CPU as well as strengthening, and accelerating the execution of AES applications.
Failure to enable AES-NI while Encryption is enabled, may result in a dramatic cpu utilization increase. In recent versions of vSAN, the Health Check UI detects, and alerts when AES-NI has not been enabled. If the BIOS does not have the option to enable AES-NI, it is most likely that the feature is always enabled.
Note: This also applies to VM encryption.
The other consideration is available space. My previous posts talk about data migration occurring if vSAN Encryption was enabled after data has been moved into the vSAN Datastore, due to the disk format task necessary. Although vSAN Encryption does not incur a space overhead for its operation, it is important to keep in mind that there needs to be enough available space to be able to evacuate an entire disk group during the configuration process.
I am a firm believer on spending a good amount of time during the design phase of any deployment. Planning ahead, and knowing your limitations will make your life easier, maybe just a little bit, but every bit helps.
If you are planning on using LACP for link aggregation on vSAN, I strongly advise you to get familiar with your options, and check the Network Design guide at storagehub.vmware.com . In the Network Design Guide here you will learn about NIC teaming options, and LACP requirements such as LAG, vDS, as well as the PROs and CONs (below).
Pros and Cons of dynamic Link Aggregation/LACP (from Storagehub)
Improves performance and bandwidth: One vSAN node or VMkernel port can communicate with many other vSAN nodes using many different load balancing options
Network adapter redundancy: If a NIC fails and the link-state goes down, the remaining NICs in the team continue to pass traffic.
Rebalancing of traffic after failures is fast and automatic
Physical switch configuration: Less flexible and requires that physical switch ports be configured in a port-channel configuration.
Complex: Introducing full physical redundancy configuration gets very complex when multiple switches are used. Implementations can become quite vendor specific.
In addition to this, you should also consider vSphere limitations while using LACP. Some of the limitations include:
LACP settings not available for host profiles
No port mirroring
Does not work with ESXi dump collector.
For a complete list of limitations, visit VMware Docs here
Be cognizant of some “gotchas” as well. For example, restarting management agents on ESXi with vSAN/LACP using services.sh script, may cause some issues. Instead use”/etc/init.d/<module> restart” command to restart individual instances. In essence if you use “services.sh restart” script to restart services, it will also restart the lacp daemon (/etc/init.d/lacp). See KB1003490
Like with any other deployment, you should consider your PROs, CONs, future plans, and environment dependencies among others.
If you are familiar with vSAN, you already know that the VCG is a “must follow” guide to success. In certain instances, deployments may use ESXi OEM/custom images based on internal policies or even personal preference. However, these type of images contain vendor specific tools, drivers, etc. One of the results from using such images is the use of async drivers for storage controllers rather than inbox drivers. For sake of demonstration, we can focus on the PERC H730.
While checking config assist, you can see a warning stating that the recommended driver per the VCG is not currently installed. In the picture below you can see that we have uncertified drivers, and we need to roll the drivers back to the correct version.
Links to download such drivers are typically found within VCG or the ESXi “drivers” tab from the downloads page. In some occasions, this link may not be present for the version that you are running. So how do I get the correct drivers? You certainly don’t want to be running drivers that have not been certified for vSAN, do you?!?! Of course NOT.
You can get such drivers from the ESXi offline bundle of the version you currently have. For example, let’s say you are running ESXi 6.5 U1. You will need to go to https://my.vmware.com, log in using your credentials, go to downloads, and select ESXi 6.5 U1 as the product. Download the Offline Bundle (zip). Once completed, unzip the file and navigate the vib folder until you find the correct driver. In this case we are looking for lsi_mr3 version 6.910.18.00-1vmw.6188.8.131.5264106. You can then take that vib and use your preferred vib install method to update your drivers.