7.0

Install and Configure vSphere Replication with SRM 8.3 on vSphere 7

Duncan Epping · Apr 2, 2020 · Leave a Comment

I haven’t really done much with vSphere Replication and Site Recovery Manager (SRM) in the past years as my main focus has been vSAN. I figured I would get two clusters up and running and install and configure both vSphere Replication as well as SRM on top of vSphere 7. Although the installation and configuration are pretty straight forward, there are a few steps which are important. Below the steps I took to get things up and running.

Deploy the vSphere Replication appliance in both clusters
Deploy the Site Recovery Manager appliance in both clusters
Go to “https://<ip of vSphere Replication appliance>:5480” in first cluster
- username: root
- password: what ever you specified!
Click on “Configuration Page” link
Specify Password of vCenter Server in the Password field
Click “Apply Network Settings”
Click “Save and Restart Service”
Accept the SSL Certificate
Repeat the above for the second cluster!
Now go to your vSphere H5 Client and wait until the vSphere Replicated tasks are completed
Log out of the vSphere H5 Client and log back in for both clusters
Now go to the first cluster / vCenter server
Now click on “Menu” and then “Site Recovery”
Click “open Site Recovery”
Click “New Site Pair”
Fill out the details of the second vCenter Server
Click Next and Connect if you get a security alert and are certain this is the correct vCenter instance
Select the correct listed vCenter instance and vSphere Replication appliance
Click Next and Finish, now you will see a task within vCenter that states “Connect vSphere Replication Sites”
Now you have vSphere Replication running and you can replicate VMs from one location to the other manually if and when desired.

Creating a vSAN 7.0 Stretched Cluster

Duncan Epping · Mar 31, 2020 · Leave a Comment

A while ago I wrote this article and created this demo showing the creation of a vSAN Stretched Cluster. I bumped into the article/video today when I was looking for something and figured that it is time to recreate the vSAN Stretched Cluster demo. I recorded it today, using vSphere / vSAN 7, and just wanted to share it with you here. Hope you enjoy it.

vSAN 7.0 UI enhancements for vSphere Replication

Duncan Epping · Mar 24, 2020 · 3 Comments

I have been playing around with vSphere / vSAN 7.0 the past week or so. Today I configured vSphere Replication between two vCenter Server instances with vSphere / vSAN 7.0. I wanted to check out the enhancements that were introduced in the UI. Although they are relatively small enhancements, I feel they will make your life as an administrator much easier. The problem people had with VMs which were replicated using vSphere Replication is the fact that the vSphere Client didn’t show much information about the objects. You could not see how much capacity was consumed, or even to what the object belonged to. vSphere 7.0 changes this! When you go to the vSAN section under Monitoring you can now in the “Virtual Objects” pane not only see the objects, you can also easily identify to which VM they belong and you can easily see the different “point in time” copies associated with the VM.

On top of that, the Capacity overview also shows you these details under “User Objects”. Interested in what it looks like? Just watch the demo below, it is just under 2 minutes, a nice quick to-the-point overview of what was introduced for vSphere Replication in vSAN 7.0

vSphere 7 and DRS Scalable Shares, how are they calculated?

Duncan Epping · Mar 16, 2020 · Leave a Comment

I wrote a post and recorded a short demo that explained this cool new feature called Scalable Shares, part of vSphere 7 / DRS, last week. I didn’t want to go too deep in the post, but now that I am getting more questions about how this actually works, I figured I would provide some examples to explain it. As mentioned in my previous post, Scalable Shares solves a problem many have been facing over the last decade or so, which is that DRS does not take the number of VMs in the pool into account when it comes to allocating resources. So as an example:

Just imagine you have a resource pool called “Test”, it is a resource pool with “normal” shares and has 4 VMs. Let’s say this resource pool has 4000 shares.

Now compare that resource pool to the “Production” pool, which has shares set to “high” but has 24 VMs. Let’s say this resource pool has 8000 shares.

This is a very extreme example, but it shows you immediately what the problem is. On a per VM basis, the VMs in the production resource pool, would receive far less resources when there’s contention as DRS would simply divvy up the resources based on the assignment of the shares of the resource pool. Test would receive 1/3 of the resource (4000 of 12000 total shares), and production would receive 2/3 of the resources (8000 of 12000 total shares). If you would divide that by the number of VMs in each pool, it is obvious that the VMs in Test are in a better situation than the VMs in Production.

So how would this work if you Scalable Shares enabled? Well, let’s list some facts first:

A resource pool looks like a VM with 4 vCPUs and 16GB of memory to DRS
Scalable Shares looks at the total amount of shares in the Resource Pool (all vCPUs!)
For a resource pool high is 8000 shares, normal is 4000 shares and low is 2000 shares
- Note, that this is based on 4 vCPUs, so the real values are 2000, 1000, 500.

The calculation would be as following:

Resource Pool Shares = (4 vCPU * Shares of Pool )* (Total number of shares of all vCPUs in resource pool)

So as an example, in the case I have Test with normal shares and 4 VMs, and Production with high shares and 24 VMs, and all VMs have a single vCPU with normal priority the calculation for those two resource pools would be:

Test = (4 * 1000) * (4 * 1000) = 16,000,000 shares

Production = (4 * 2000) * (24 * 1000) = 192,000,000 shares

In other words, Production has 12 times more the number of shares as Test has when Scalable Shares is enabled. I hope that clears things up!