vNiklas Virtualization blog

I have today tested how it works to hot-add both memory and vCPU to a virtual machine running Windows 2008 R2 Datacenter Edition, this machine also has SQL 2008 R2 Enterprise edition installed.

First i had to enable hot-plug in the virtual machine, there is of course two ways to do this, either via the GUI or

the powerCLI way:

$vmConfigSpec = New-Object VMware.Vim.VirtualMachineConfigSpec
$mem = New-Object VMware.Vim.optionvalue
$mem.Key="mem.hotadd"
$mem.Value="true"
$vmConfigSpec.extraconfig += $mem
$cpu = New-Object VMware.Vim.optionvalue
$cpu.Key="vcpu.hotadd"
$cpu.Value="true"
$vmConfigSpec.extraconfig += $cpu

$vm = Get-VM TempNHot | Get-View
$vm.ReconfigVM_Task($vmConfigSpec)

when this has been executed on the particular VM i can then when it is running use powerCLI again and add resources to it.

Get-VM TempNHot | Set-VM -MemoryMB 3072 -NumCpu 4 -Confirm:$false

According to Microsoft documentation it is only supported to do hot-add of memory and CPU in Datacenter edition of Windows, Also regarding SQL you have to use either Enterprise or Datacenter edition to also get it working into the application.

To check that the new resources where used i tested with the SQLstress application to get some load on the SQL server and check the taskmgr, but it did not show that the load where spreading to the new added vCPU, after some research i found out that the SQL server do not start to use new hardware right away, it need to be reconfigured to schedule load on additional CPU´s, so there is a little manual intervention but no downtime on the server!

before:

So i started a query in SQL Management Studio and wrote

RECONFIGURE;
GO

After :

In the taskmanager i could now see that all four vCPU where equally loaded by the SQL server.

Maybe it is not so common to have to do this but if you set up a large Tier-1 SQL server in a virtual world you surely want to be able to hot-add resources when it is loaded. Think of the advantages that this brings when you actually both can add memory and cpu resources without any downtime!

In a virtualization world we always recommend our customers to buy Windows Datacenter licenses on their hosts so using it on a VM will not add any extra cost. The SQL server is of course quite a price jump from standard to enterprise but if your big SQL server uses more than 64 GB ram you will still need to use Enterprise licenses

I want to share my latest automation scripting, i am in a project where we are in-sourcing from a hosting company. We have connected the hosts to the outsourcers NFS share, of course with powerCLI, when doing it this way i get the datastores on all servers in our cluster, without the risk of differences between the hosts datastores.

# Create NFS shares on all hosts
#
# Niklas Åkerlund /RTS
$NFSdatas = Import-Csv -Path "nfsdatastores.csv" -Delimiter ";"
$VIHosts = get-cluster -Name Cluster1 | get-vmhost | where {$_.ConnectionState -eq "Connected"}
foreach ($VIHost in $VIHosts){
foreach ($NFSdata in $NFSdatas){
$NFSHost = $NFSdata.Host
$NFSshare = $NFSdata.Share
$NFSShareName = $NFSdata.ShareName
if (($VIHost | Get-Datastore | where {$_.Name -eq $NFSShareName -and $_.type -eq "NFS"}-ErrorAction SilentlyContinue) -eq $null){
Write-Host "Monterar NFSstore $($NFSShareName) på $($VIHost)"
New-Datastore -Nfs -VMHost $VIHost -Name $NFSShareName -Path $NFSshare -NfsHost $NFSHost
}
}
}

Now when we have this in place, during the transitions the hosting company shut down the VMs on their hosts that we are going to take over.  And we add the VM to the inventory on our vCenter, when doing this the vmdk got a different datastore id in the config, also some settings should be updated to the corporate standard for the virtualization platform at the customer.

# Script to update VM with vmdk and right settings
#
# Argument in is VM name
# Niklas Akerlund / RTS AB 2011

$VMname = $args[0]
if ($VMname -ne $null){
$VM = Get-VM $VMname
$Datastore = Get-Datastore -VM $VM
$HDDs = Get-Harddisk -VM $VM

# Remove incorrect hdd referenes

Remove-HardDisk -HardDisk $HDDs -Confirm:$false

foreach ($HDD in $HDDs){
$HDDname = $HDD.Filename
$HDDsNames = $HDDname.Split("/")
$count = $HDDsNames.count
$VMdkName = $HDDsNames[$count-1]
#Write-Host $VMdkName
$diskpath = "[" + $Datastore.Name + "] " + $VM.Name + "/" + $VMdkName

#Write-Host $diskpath

New-HardDisk -VM $VM -DiskPath $diskpath
}

# Reconfigure VM Settings

$spec = new-object VMware.Vim.VirtualMachineConfigSpec
$spec.MemoryAllocation = New-Object VMware.Vim.ResourceAllocationInfo
$spec.MemoryAllocation.Limit = -1
$spec.CpuAllocation = New-Object VMware.Vim.ResourceAllocationInfo
$spec.CpuAllocation.Limit = -1
$spec.tools = New-Object VMware.Vim.ToolsConfigInfo
$spec.tools.toolsUpgradePolicy = "manual"
$spec.swapPlacement = "inherit"

$VM = $VM | get-view
$VM.ReconfigVM_Task($spec)
}

After this we start up the VM and later we do a storage vMotion of the VM to the customers FC-SAN

Get-VM theVM | Move-VM -Datastore fcdatastore1

Today i have found a limitation using host profiles and this together with a vmkernel port that has Mtu 9000 activated. maybe it has not been a requirement when designing the host profiles?

We set up the reference host with 4 vmkernel ports, one for management, one for vmotion, one for FT and one for NFS. The port that we wanted to use Jumbo frames for was the vmotion port.

As i wrote in an earlier post, I used the powerCLI to configure the Mtu for the actual vmkernel port Get-VmhostNetworkAdapter -Name vmk1 | Set-VmhostNetworkAdapter -Mtu 9000.

Then i add this host as an reference host in the Host Profiles and attach it to the cluster. Adding a new host and then Apply profile, creates all our vmkernel ports correctly but when checking what Mtu the vmotion vmkernel port got, it is created with the default Mtu of 1500. This is not so good because i do not want to use several different ways to configure and i want to be able to trust the Host Profiles solution. The only vmkernel port that was created before applying host profiles was the management port so it has nothing to do with editing exisiting. So the result is that i need to after applying a host profile, run a powerCLI command to edit the Mtu.

Strangely no matter if the Mtu is 9000 or 1500 the hosts are compliant in the GUI..

This applies to vSphere 4.1 u1 (i do not know how this behaves in vSphere 5)

Conclusion of this is that I have to think a bit more about using the Host profiles. If it is not fully implemented then it is not usable to get uniform hosts.

According to the KB 1038827 “Enabling Jumbo Frames for VMkernel ports in a virtual distributed switch”, VMware says that you have to recreate the vmkernel port to set the MTU for jumbo frames. This is not true if you use powerCLI, I do not know exactly how it is done beneath the hood but it is very easy to configure using quite a few lines scripting..  By the way, there is no way in the GUI to edit this.

$cred = Get-Credential
Connect-VIServer ESXhost.test.loc -credential $cred

Get-VMHostNetworkadapter -name vmk2 | Set-VMHostnetworkadapter -Mtu 9000

Get-VMHostnetworkadapter -name vmk2 | ft Mtu

Setting the Mtu on the vmkernel port is basically not different using a standard vSwitch or a distributed vSwitch.

Of course you can connect to a vcenter and add a foreach loop to set the Mtu for more than one host vmkernel port.

I have had the opportunity to do some PowerCLI scripting on an installation where we have  vDS (virtual Distributed Switch). In the PowerCLI there is not so much cmdlets for the distributed switches, that is kind of awkward as there is so many cmdlets for everything else.. Luckily LucD had made some nice functions for me to use when creating the port groups.

I used his function for creating port groups, as the customer had about 20 vlans that needed to be added it was a perfect match to do it by powerCLI because setting up this manually is boring! So i had a csv file with the name and vlan id which i ran through in a foreach loop, then all was done.

# Create Distributed virtual portgroups for each VLAN
# Niklas Åkerlund / RTS AB 2011-09-09
#

$Datacenter = "datacenter"
$vDSName = "dvswitch01"
$vDSPortGroupPorts = 128

# Call Functions from motherscript
. .\Set-vDS-Porgroup-functions2.ps1

$vDS = Get-dvSwitch -DataCenterName $Datacenter -dvSwitchName $vDSName
#Write-Host $vDS
$vlans = Import-Csv vlan.csv -Delimiter ";"

foreach ($vlan in $vlans){
$name = $vlan.Name
$vlanid = $vlan.VLAN
if ($name -ne ""){
Write-Host $name
New-dvSwPortgroup $vDS $name -PgNumberPorts $vDSPortGroupPorts -PgVlanType "VLAN" -PgVlanId $vlanid
}
}

But then we realized that we needed to change some settings with both the security and load balancing so i had to remove all my port groups and start over.. I did not want to remove them manually and the powerCLI cmdlet that removes standard port groups could not be used on a vDS, I did not find the code from LucD in his blog to remove a vDS port group so i came up with the brilliant idea to use Onyx, it is a tool from VMware Labs that interprets the traffic between the vSphere Client and the vCenter and transform it to powerCLI code or .Net or SOAP or Javascript.

I then after starting this tool connected to my vCenter and through the vSphere Client removed a vDS port group, i got the powerCLI code (which I probably could have found out being a bit smarter in powershell/powerCLI without Onyx, but now I´m not ) So i did a small script to find all my vDS port groups and remove them.. Note that i cannot remove a vDS port group that already has been populated with connected VM´s.

# Remove vds port groups
#
# Niklas Åkerlund / Real Time Services AB

$vlans = Import-Csv vlan.csv -Delimiter ";"

$PGs = Get-VirtualPortGroup

foreach ($vlan in $vlans){
foreach ($PG in $PGs){
if ($vlan.Name -eq $PG.Name){
$destroy = $PG.Id
#Write-Host $destroy
$pek = Get-View -Id $destroy
$pek.Destroy_Task()
}
}
}

And now i could run the add script again with the added parameters for more security and load balancing.

New-dvSwPortgroup $vDS $name -PgNumberPorts $vDSPortGroupPorts`
-PgVlanType "VLAN" -PgVlanId $vlanid -SecPolMacChanges:$false`
-SecPolForgedTransmits:$false -TeamingPolicy "loadbalance_loadbased"

After the vacation this summer i have had much to do and not any time for blogging, i will try to behave better and keep you readers updated in my findings..

I just want to clarify for those of you running several vCenter installations for your different virtualization platforms and use vCenter Update manager for updating your hosts.

When you install the vCenter update manager you can only add one vCenter and there is no support for using the same Update manager for several vCenter instances. From a management point of view it would have been a nice feature to be able to use the same vCenter Update Manager for several vCenter instances in a linked mode, as you would only have one to handle.

In the Update Manager documentation it clearly says : “The Update Manager installation requires a connection with a single vCenter Server instance. “  link to vSphere 5.0 vum installation documentation is here , This is not new for the 5.0 and is also the case for earlier versions of vCenter and VUM

Today I have helped a customer with ther vCenter database and the rollup jobs that was not present..

Yesterday i noticed that they had missed to update the stat jobs when moving their database to another server (I gave them the KB 7960893 link so they could move the db. allthough they missed step 5 in that list.). This was leading to an growing database and that the performance stats where not being updated. ultimately if the database grows to much and fills the disk the vCenter server will stop. I showed them the KB 1004382 that descripbes how you update or create new stat rollup scripts for your vCenter database, this was not successfull because they did not select the right database for the creation of the jobs..

Again i used the wonderful tool Teamviewer and connected to the customer and helped them to correctly create the jobs.

One important thing is to select the right database when running the script or it will not work when it is going to run.

As you can see on the screendump, for one that is not to familiar with SQL management studioi you must select the database beside the ! Execute before executing, the script will run and create a stat rollup job but it will not work because it is looking for stored procedures that are in the vCenter database..

If you not have logged on as the owner of the database (your vcenter service account) you should edit the jobs to be run as that account!

I have now tested the script that Hugo Peeters has made for checking what licensing needed with a vSphere platform when upgrading to V,

Of course this is a small platform and we do not have so much machines running, but the point is that it is a cool script that gives you a hint where you are and what your platform need in amount of licensing.

One thing my colleagues has missed and i wanted to touch and highlight is the vRAM and the pooling, i think it is well documented in the vSphere licensing, pricing and packaging document

The new licensing model is as follows

• No more restrictions on cores
• No max physical RAM limit
• You still need one license/pCPU
• Not allowed to mix different vSphere editions in the same vRAM pool, if using more than one edition managed with vCenter it will create different vRAM pools

for each license model there is a vRAM entitlement 24 GB for standard, 36 GB for Enterprise and 48 GB for Enterprise+, these are shared when connected to a vCenter so if you have a virtual machine on a host with 2 pCPU 192 GB physical RAM (with E+ you have 96 GB vRAM) and this VM has been configured with 128 GB vRAM and in your vmware vSphere cluster that this host resides have 3 other hosts with same setup and that will give you 384 GB vRAM in the pool, 384 – 128 equals 256 GB left to use for other VMs before bying more licenses.  Also if you have a linked vCenter and hosts with vRAM that is also included in the pool to be used. What i am trying to say is that although you have used more vRAM than assigned for one host you are still compliant as it is part of a pool.

As in all virtualization design you must calculate for host failures and its vRAM can be used when one host is down for maintenance or failure.

In the above example you can add more licenses for getting more vRAM, these licenses can later be used for adding a new host and for that physical CPUs.

Hope this gives some more light in the jungle

I have been investigating some things that need to be considered when deploying a Microsoft Cluster on a VMware platform.

As you can see on the graph, there are some different supported configurations. The kb 1037959 shows more information, i will try to highlight some things below.

Why i started this was because i was looking at the Multipathing polices for a customer and we discussed in the office that we preferred the Round-Robin policy, This is as you also can read on the KB not supported for the RDM shared disk, so if you already have  Round Robin as default on your hosts you have to set another policy on that specific LUN.

This can be done by powerCLI or by the vClient GUI, and as i am a big fan of powerCLI i will show you the command for it

VMHost hostname.test.local | Get-ScsiLun -CanonicalName "naa.60054242555" | '
Set-ScsiLun -MultipathPolicy "fixed"

If your default multipathing policy is set to one you do not want you can edit the default both with VMware CLI and powerCLI, as for the last there is a script that Stephen has made and can be found on the VMware Communities forum. otherwise you will have to change policy on every new datastore you add manually.

If you have a iSCSI SAN you will use in-guest iSCSI connection to the shared storage, then there is no need to change multipathing polices, what i do not understand and have not got any good information about is when i use in-guest shared storage, why do VMware have a limit of two cluster nodes that they support? As I see it the limit should be what MSCS has as a limit and that is 16 nodes, maybe there is no need for such a big cluster as you already have HA in your virtualization platform. If the setup as you can se in the graph is a cluster without shared storage it is not any limits set on number of nodes.

You will also need to edit your VMs scsi controller, for the Win 2008 you must have the LSI SAS controller installed, there is a KB 1002149 for that where the steps are outlined. The shared disk must reside on a dedicated scsi controller.

You will also have to setup Anti-Affinity rules in DRS to keep your cluster nodes apart, if you have for some reason decided to setup a CIB (Cluster in a Box) then you will need to setup an affinity to keep them together on the same host. For the VMs that are used for clustering you should set the DRS to partially automated.

For more information how to setup look at the VMware documentation on setup of failover clusters pdf

In two days i have had the opportunity to test the Compellent SAN solution and i find it really cool and smooth. When integrating it with your vCenter you get the single pane of gui to handle the whole solution. You have to on every vmware client install the Compellent plugin to be able to administer the compellent and get the tabs that are plugin specific, you will also have to add the compellent management address and also a user with password and of course some rights to do SAN stuff.

After adding the Storage Center you get the following tabs:

As you can see on the Compellent view, you can add and remove datastores, if this is done in here the compellent plugin will also format the datastore with vmfs and rescan datastores on the hosts. Also as you see on this screenshot you can for each datastore see where your data is and how much of it resides where, Tier 1 is the fastest and if you have setup with more than two different hdd you will get a Tier 2 and a Tier 3. The active blocks are moved to faster or slower disk depending their demands.

With the Replay function you can get SAN backup functionality and also for full consistent backup you can install a agent in the VMs to get them to prepare a vss snapshot before running the replays. Really cool to be able to take SAN snapshots this way.

another thing as you can see also on the screenshot is that the datastore is 2 TB but only 9,32 GB is used! Of course you have to size your solution to cope with the amount of data that you are going to store.

When deleting a Datastore you get the following choices, if you put it in the Recycle bin, you can get it back as long as not the space will be needed by some other data, as long as there is space in the Compellent you can restore the datastore and that can be handy if you had some VMs that you need later and did not migrate to another datastore.

The Compellent solution is very powerfull and has much more functions than i have highlighted here, i hope that i will get some more time to test and use it in the near future!