In this video, learn how to create a new vSphere 6.7 datastore on an iSCSI LUN, format it with VMFS6, and configure datastore size and block size on the LUN. Also, learn how datastores are identically presented to all connected hosts and how to unmount and delete datastores.
- [Rick Crisci] In this video, I'll demonstrate how to create a new VMFS datastore. So I'm going to click on my storage tab. And under my storage tab, you can see I've got a couple of datastores already created here. I'm going to right click on my training virtual data center. I'll go down to storage. I'll choose new datastore. And I'm going to create a new VMFS datastore. So, hopefully I have a LUN available that I can utilize to create this new VMFS datastore. I'll choose VMFS, I'll hit next, and I'm going to name this datastore iSCSI_DS1. So this is my first datastore. I'm creating, that's going to be a VMFS datastore. And then, I need to choose a host here, So I've only got one host in my environment at the moment. I'm about to add another one, but I only have one host at the moment. So I'll just choose that host and here you can see, all of the LUNs that this host has available to it. So, basically, think of these LUNs as essentially these chunks of disk space. Chunks of available space, that are being presented either on local disks or through some sort of storage array, and that's what we've got here. An iSCSI storage device. That I can go ahead and create a datastore. So what I'm doing is I'm going to grab LUN0 and the 9.9 gigs of capacity that it's offering me, and I'm going to format that capacity and create a VFMS datastore out of it. Now, all of the hosts, in my vSphere environment, our vSphere 6.7, and their not going to have any problem with VMFS6. So, I'm going to go ahead and choose VMFS6 because it supports automatic space reclamation. So it's going to be more space efficient. So, VMFS6 is the latest and greatest version of VMware's file system, that was introduced in vSphere 6.5 and it has a few substantial enhancements versus VMFS5. But the most important thing that I want you to understand is there is no direct migration or upgrade path. So, if I create a VMFS5 datastore? I cannot upgrade it to VMFS6 later on. I have to just basically migrate all the virtual machines off of it, to a VMFS6 datastore. So, there's no upgrade path from VMFS5 to VMFS6. Basically, I just create VMFS6 datatstores and then move everything to them. And these VFMS6 datastores feature automatic space reclamation. Which is a critical feature, really important, and is going to greatly reduce the amount of dead space sitting on these datastores. And now based on what you see on this screen here, it can be a little misleading, I just want to point out that both VMFS5 and VMFS6 support LUNs that are greater than 2 terabytes so don't think that because you are choosing VFMS6 um, your not able to do a LUN that's larger than 2 terabytes. That's not the case. VMFS6 also supports storage devices that are greater than 2 terabytes. And if you're looking to kind of dig into the differences between the versions of VMFS datastores, you can find all sorts of information on VMFS6 versus VMFS5 here at docs.VMware.com Here you can see the support for larger than 2 terabytes is present on both VMFS5 and VMFS6. So, that's the critical thing to understand here, is that if you have the option and all your hosts are later than esxi 6.5, go with the VMFS6 datastore. And you'll notice that if you're doing esxi 6 or earlier? VMFS6 is not supported. So that's really the only case in which I should be selecting VMFS5 at this point, is if I still have some of those legacy esxi hosts. Okay, so in this case, I'm choosing VMFS6. I'm going to take all of this space available on this LUN and dedicate it to this datastore. And here I can choose the block size and the space reclamation granularity. And so, basically, what this is going to tell me is hey, any deleted or unmapped blocks are going to be reclaimed on the LUN at low priority. So basically, what this means is space that is no longer being used, will eventually get reclaimed from that LUN and freed back up so it can be used again. And again this is a significant enhancement versus VMFS5. So, I'm going to hit next here, and that's it. Ready to complete. So, I'll finish this process and my new datastores should show up right here. There's my iSCSI datastore. It's been formatted with VMFS6 and I can see the hosts that have this datastore available right here. And at the moment there's only one esxi host that can access this datastore. So I'm going to pause my recording for a moment and go ahead and add a second esxi host to my inventory. Okay, so now I've got a second esxi host added to my inventory So, I'm going to go ahead and grab this host and I'm going to do this extremely quickly. I'm going to add a new software iSCSI adapter. I'm going to go ahead and set it up to query the same iSCSI storage array. That the other esxi host is querying. Just like we saw in the previous video. And then I'm going to run a quick re scan of storage so that my new host can find all of the available LUNs on that storage array. Okay, and there we go, after re scan on the second host I'm now seeing these LUNs available. So, here's where it gets interesting. I created a datastore and if you look at this host 192.168.199.1 here is the iSCSI datastore that I created. And then after the fact, after that was already done, I added a new host to inventory. And here we see on this second host, that datastore's already available. I didn't do anything to add that datastore to that second host. All I did was create an iSCSI initiator on the second host. I pointed that storage adapter towards the storage array that I wanted it to discover, and when it went through dynamic discovery, it discovered the available LUNs on that storage array and it found that on one of those LUNs we've got an iSCSI datastore already created. So it mounted that iSCSI datastore and made it available on this host as well. So now I have two esxi hosts that both have access to shared storage. They both have access to this iSCSI datastore 1. And if I go ahead and add a new datastore, I'll just do this under host 192.168.199.11 if I go ahead and add a new datastore, I'm going to grab another one of these LUNs off of my VMFS storage array. I'll call it iSCSI_DS2. Next. I'll choose VMFS6. I'll use all of the available space and I'll hit finish. And now I've got iSCSI datastore 2 available on host 11. If I go down to host 12, it's automatically there as well. So that's the beauty of shared storage. You create a datastore that's available on one host? That datastore becomes available on that other host, as long as that other host is also connected to the same storage array and has access to that same set of LUNs. Okay, so now we've created a couple of iSCSI datastores. Let's take a look at what else we can do with these. So, I can right click an iSCSI datastore and I can choose to unmount it. So let's do that. Let's unmount this iSCSI_DS2. I'm going to pick one particular host to unmount it from. And once that datastore is unmounted it'll be unavailable on this second host. The other thing that you can do with the datastore, so I'm going to right click this datastore one more time and choose delete datastore. Now, here's what's going to happen when you delete a datastore. When I created this VMFS datastore, what happened was, a LUN on my iSCSI storage device was selected. That LUN was formatted with VMFS6 and the datastore was created. If I choose to delete this datastore what's going to happen is all of the data on that datastore is going to be destroyed. Everything on this datastore is going to be permanently erased. It's going to actually remove the VMFS datastore from that LUN and destroy all of the data on it. So just kind of bear that in mind. With and iSCSI or with any VMFS datastore. If you delete the datastore? Not only are you deleting it for this host, you're also deleting it from this host. And you're actually deleting all of the data on the storage device itself. So, deleting a VMFS datastore, is something you cannot undo. Once it's done, you've destroyed all of that data. If you have a backup, you could restore from backup. But deleting a datastore is permanent and it's going to destroy all of the data on that datastore for every host that uses that datastore. So just exercise caution whenever you have to delete a VMFS datastore.
Note: This series is also designed to prepare candidates for the VMware Certified Professional - Data Center Virtualization 2019 (VCP-DCV 2019) exam.
This course was created by Rick Crisci. We are pleased to host this training in our library.
- Storage performance
- VMFS and NFS data stores
- Connecting hosts and storage with iSCSI
- iSCSI and ESXi 6.7
- Storage DRS clusters
- vSAN disk groups
- Virtual Volumes
- Storage IO Control (SIOC)