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Showing posts from 2020

How to Copy Azure Images to Other Subscriptions or Regions

The Azure image was introduced in 2014 by Microsoft. It's a more comprehensive image for Microsoft Azure Virtual Machines. Azure is a highly available cloud. Solution design needs to always take failover and tolerance into account. Therefore, copy Azure images to other subscriptions or regions is something we need to consider. There are three methods to copy Azure images to other subscriptions or regions: Option 1 Firstly, the easiest way to achieve that is to use the Image Gallery . It's introduced in the middle of 2019. As Microsoft states: " Shared Image Gallery provides a simple way to share your applications with others in your organization, within or across Azure Active Directory (AD) tenants and regions. This enables you to expedite regional expansion or DevOps processes and simplify your cross-region HA/DR setup. " The high-level procedure is to create a new Image Gallery, create image definition and version, and then add replica regions in the version. If yo

VM Share Host VPN Connection on VMware Workstation

You may need to access the internet with a VPN for privacy or performance. The most popular VPN solution is Shadowsocks . If you are an IT Pro, you may face a similar issue that I'm facing: How does VM share host VPN connection? My home lab is running on top of VMware Workstation on a Windows 10 computer. The virtual machines use the NAT network to communicate outside. It goes over the internet through my ISP directly. The performance of AWS or Azure is slow. I tried Shadowsocks on the Windows 10 computer. The performance is good. But Shadowsocks is not like other VPN solutions. Its only functions for the host computer (The Windows 10 computer). I had to run Shadowsocks client on each virtual machine to get the better speed. I read an article that is talking about how to share host VPN with VirtualBox. It gave me some ideas. The solution is actully similar: Make sure the " Allow Clients from LAN " option is checked in the Shadowsocks client. Find out the IP address of

vCenter is not sending email alerts

It’s useful to get email notification when there is an alarm raised in vCenter Server. To configure the function. You need a valid SMTP server. And configure the SMTP server on vCenter Server. If there is a problem that vCenter Server is not sending email alerts. We need to isolate is it a vCenter Server side issue, or an SMTP server problem. Therefore how to identify problem source is important. VMware moved vCenter Server to a customized Linux based platform since 5.5. It’s easy for administration, but limited ability in troubleshooting. You may notice that the telnet command is not available when troubleshooting the SMTP issue. The following is how to troubleshoot such an issue on the vCenter Server virtual appliance. Firstly, you need to ping the IP address and FQDN of the SMTP server. Make sure the basic connectivity between the vCenter Server and SMTP server is working. Second, try to reach out to SMTP service on the vCenter Server to make sure the SMTP protocol can be establish

How to reset Azure Migrate Appliance

Azure Migrate appliance is a simple tool to move VMware virtual machines to Azure. But it has limitation to migrate VMs on multiple vCenter servers. In other words, you have to deploy multiple appliances to support multi-vCenter. This is a time-consuming task. In fact, there is a way to reset the Azure Migrate Appliance. There is a file appliance.json in Azure Migrate appliance. It stores the key information of the Azure Migrate project. The credentials, vCenter server, and key vault information are all stored in the file. Also the registration status. The file is located in C:\ProgramData\Microsoft Azure\Config\ . It's a JSON file. The variable IsApplianceRegistered indicates if the appliance registered or not. Change the value from True to False will reset Azure Migrate appliance status. Of course, you still need to reboot the appliance. This reset is no impact to stored credential and vCenter server data.

Quick Note: Mouse Jumps Around in VMware Workstation

I just upgraded a testing machine to Windows 10 1909. And installed VMware Workstation 15 latest version on the testing machine. Somehow the mouse jumps around in VMware Workstation when the mouse pointer is grabbed by a VM. This is very annoying. I only observed this issue when run VMware Workstation in remote desktop session. I didn't see the same issue when I run a VM on a local computer. The reason is the testing machine has WDDM graphic driver installed. You can disable WDDM graphic driver in remote desktop session by modifying group policy. Open group policy editor by following command: gpedit.msc Go to Computer Configuration -> Administrative Templates -> All Settings Disable the setting: Use WDDM graphics display driver for Remote Desktop Connections . Reconnect the remote desktop session. Please refer to following VMware KB to understand more about WDDM. WDDM and XPDM graphics driver support with ESX, ESXi, Workstation and Fusion (1016770) It's not clear why t

OneDrive Can't Add Your Folder Right Now!

This post is nothing related to servers. I post that since I couldn't find anything on the internet about this issue. This " OneDrive Can't Add Your Folder " spent me quite a while to figure it out. I only found an article talks about IRM after I figured the issue out. So I think it's maybe valuable to document that. I re-installed the testing machine by different OS versions several times. It's just happened suddenly. My OneDrive cannot sync any files. I upgraded the client to the latest version but no luck. The error message I got initially was: We can't sync your OneDrive - xxx Following these steps to fix the problem: 1. Go to, click the Settings icon in the top-right, then click "Site settings". 2. Under "Site Administration", click "Site libraries and lists". 3. Click "Customise Documents". 4. Click "Information Rights Management" and clear the checkbox. Then I upgraded O

[Quick Note] Failed to install pywinrm on CentOS 8

You may see error message " Running install for pykerberos … error " when install pywinrm on CentOS 8. The additional errors are " unable to execute 'gcc': No such file or directory " and " command 'gcc' failed with exit status 1 ". The reason because gcc dependence is missing on the machine. You need to run following command to install gcc then try install pywinrm again. # yum install gcc

Balanced Memory Configuration for ESXi Servers

Background ESXi servers are fundamental infrastructure. The underly hardware performance has a butterfly effect on the upper layer virtual machines and applications. Since there is less than 10% performance overhead on the virtualization layer. So it's valuable to get full performance on the hardware layer. Memory is a big player in hardware performance tuning. Balanced memory configuration is very important. I wrote an article " LRDIMM or RDIMM on ESXi hosts? " a long time ago. It was the understanding in 2016. I did some research recently. I hope the following study help with your hardware decisions. This study is based on Intel Xeon 2 nd Generation Scalable Processors. 1. Basic Concepts Before we talk about balanced memory and optimized memory. Let's take a look at some basic concepts which will be used in the article. 1.1 Memory Channel The memory channels control reading and writing bandwidth operations between the CPU and memory modules. Think about it like the

Quick Note: Microsoft Remote Desktop Connection Manager Windows overfit High DPI Screen

4K screen is getting popular in recent years. You may see some challenge for legacy applications. Such as "Microsoft Remote Desktop Connection Manager". It's stopped developed since 2014. But it's still a useful tool for server administrators. You may see the windows overfits screen on 4K display. The fix is: Go to properties of " RDCMan.exe " " Compatibility " tab " Change high DPI settings " Uncheck " Override high DPI scaling behavior ".