Skip to main content

Unknown status of Hardware Acceleration

When I read VMware documents, there is a cool feature Hardware Acceleration I found in storage book. That recall me an outage about one year ago, our NetApp filer was crashed due to motherboard problem, part of datastores was failed, we have to move virtual machine from the filer to other. We noticed the storage vMotion performance was pretty high, the data moving speed was 2 times less than regular storage vMotion. That’s the advantage of Hardware Acceleration.

The first thing of this year is standardize the virtualization environment. I found an interesting problem when I checked the Hardware Acceleration part, same luns show different status on different ESXi 5 host of a cluster, some of the hosts show Hardware Acceleration enabled, and some show Unknown.

The storage is EMC Clarion CX series with ALUA enabled, I found working hosts attached VAAI filter, non-working hosts had nothing.

Working Host

Figure 1   Working Host

Non-working Host

Figure 2   Non-working Host

ESXi 5 automatic attach different filter according to lun properties, that issue indicates the lun properties was different on different ESXi 5 host, that’s a storage layer issue, after troubleshooting with EMC, we found Failover Mode of luns was different on each host, the Failover Mode should be 4 instead of default 1.

Please be aware of that storage activity on particular host will interrupt when you change Failover Mode, please put the host in maintenance mode first.

Regarding Failover Mode, I had discussion with a storage engineer, he told me different storage vendor have different name for “Failover Mode”, some storage vendor may request choose OS type of target machine. For EMC, there are 5 modes, please refer to page 10 on EMC document

Popular posts from this blog

Connect-NsxtServer shows "Unable to connect to the remote server"

When you run Connect-NsxtServer in the PowerCLI, it may show "Unable to connect to the remote server".  Because the error message is a little bit confusing with other login issues. It's not easy to troubleshoot. The actual reason is the NSX-T uses a self-signed certificate, and the PowerCLI cannot accept the certificate automatically. The fix is super easy. You need to set the PowerCLI to ignore the invalid certificate with the following command: Set-PowerCLIConfiguration -Scope User -InvalidCertificateAction:Ignore -Confirm:$false

Setup Terraform and Ansible for Windows provisionon CentOS

Provisioning Windows machines with Terraform is easy. Configuring Windows machines with Ansible is also not complex. However, it's a little bit challenging to combine them. The following steps are some ideas about handling a Windows machine from provisioning to post configuration without modifying the winrm configuration on the guest operating system. Install required repos for yum. yum -y install yum -y install yum -y install yum -y install epel-release yum -y install yum-utils yum-config-manager --add-repo Install  Terraform . sudo yum -y install terraform Install  Ansible . sudo yum -y install ansible Install  Kerberos . yum -y install gcc python-devel krb5-devel krb5-libs krb5-workstation

How to List All Users in Terraform Cloud

Terraform has a rich API. However, the API documentation does not mention how to list all users. We can leverage the organization membership API and the PowerShell command  Invoke-RestMethod  to get a user list. 1. Create an organization token in Terraform Cloud. 2. Create the token variable ( $Token ) in PowerShell. $Token = "abcde" 3. Create the API parameters variable in PowerShell. $params = @{ Uri = "" Authentication = "Bearer" Token = $Token ContentType = "application/vnd.api+json" } Note: You need to replace ZHENGWU with your own organization name. And I used 100 at the end of the URI to retrieve the first 100 users. It can be any number.  4. Retrieve the API return and list the user's email address. $Test = Invoke-RestMethod @params $